No matter where you look, just about every creature
is obsessed with:
sex, real estate, who's the boss, and what's for dinner.
The Intelligence of Dolphins
(includes Dolphins, Porpoises and Orcas - Killer Whales)
Dolphins have individual names,
their own signature whistle.
The mirror test is an experiment developed in 1970 by psychologist Gordon Gallup Jr. to determine whether an animal possesses the ability to recognize itself in a mirror. It is the primary indicator of self-awareness in non-human animals and marks entrance to the mirror stage by human children in developmental psychology. Animals that pass the mirror test are: Humans older than 18 mo, Chimpanzees, Bonobos, Orangutans, Gorillas, Bottlenose Dolphins, Orcas (Killer Whales), Elephants, and European Magpies. Others showing signs of self-awareness are Pigs, some Gibbons, Rhesus Macaques, Capuchin Monkeys, some Corvids (Crows & Ravens) and Pigeons w/training.
2-6-20 Beaked whales may evade killer whales by silently diving in sync
When hunting, the mammals dive deep as a silent group and ascend far from where they dove. Beaked whales have a killer whale problem. More formidable whales, of the sperm or pilot variety, have the size and muscle to flee or defend against a killer whale, an ocean superpredator. Smaller prey, like dolphins, can find safety by swimming in large pods. Certain toothed whales even communicate in pitches killer whales can’t hear. But elephant-sized beaked whales, named for their pointy snouts, have none of these advantages. These extreme divers swim in small groups, are too slow to outswim a killer whale, and rely on audible clicks to echolocate food deep in the ocean. Killer whales (Orcinus orca) should be able to hear them hunting below and easily pick them off as they ascend. But beaked whales have evolved a sneaky trick. An unusual, highly synchronized style of diving helps them silently slip past killer whales when surfacing to breathe, researchers describe February 6 in Scientific Reports. Predation from killer whales has shaped that strange behavior, the scientists say, and also might explain why naval sonar exercises, which can sound like predators to beaked whales, cause mass beaching events (SN: 3/25/11). “Beaked whales are some of the most mysterious mammals in the world,” says Natacha Aguilar de Soto, a marine biologist at the University of La Laguna in the Canary Islands, Spain. This group of 22 whale species can dive deeper than any mammal, sometimes descending more than 2,000 meters to noisily hunt small fish and squid using echolocation for up to 2½ hours before surfacing. Previous research has hinted that, when beaked whales return from the deep, they don’t come straight up for air like other whales. Instead, they ascend at a gradual angle, surfacing far from where they dove. “It’s highly unusual for whales to do this,” Aguilar de Soto says. She and her colleagues wondered whether it could help beaked whales slip past predators.
1-1-20 Bottlenose dolphins are splitting into two different species
Bottlenose dolphins in South America may be splitting into two different species right before our eyes. Their distinct genetic variations may have come about due to their differing habitats. Along the coastlines of southern Brazil, Uruguay and Argentina in the South Atlantic Ocean, common bottlenose dolphins (Tursiops truncatus) that live near the shore don’t look like their cousins that live further out to sea. They are longer, lighter and have a triangular dorsal fin, in contrast to the offshore dolphins’ hooked dorsal fin and darker skin. The two kinds of common bottlenose dolphin live differently from one another, too. Those in the coastal “ecotype” form small groups in bays and estuaries and don’t stray too far from home, while those in the offshore ecotype live in pods of hundreds and roam widely. When Ana Costa at the University of Glasgow in the UK and her team looked at the dolphins’ skeletons, they found still more differences: the offshore dolphins had shorter and more plentiful vertebrae than the coastal variety. “This is a charismatic, worldwide species, and it is one of the most well-studied cetacean species. Thus it is surprising that, up until now, these differences went undetected,” says Costa. The dolphins were so physically and behaviourally different that Costa wondered if the two groups had gone down different evolutionary paths, separating into two species – meaning that the ecotypes had stopped interbreeding. To find out, she and her colleagues collected more than 250 tissue samples from common bottlenose dolphins of both ecotypes off Brazil’s coast and analysed the DNA. They also compared the skulls of 106 dolphins from the same region. The genetic and skeletal differences were closely grouped together by ecotype, and genetic analysis revealed little evidence of recent interbreeding between the two varieties.
12-9-19 Grandmother killer whales boost survival of calves
Grandmother killer whales boost the survival rates of their grandchildren, a new study has said. The survival rates were even higher if the grandmother had already gone through the menopause. The findings shed valuable light on the mystery of the menopause, or why females of some species live long after they lose the ability to reproduce. Only five known animals experience it: killer whales, short-finned pilot whales, belugas, narwhals and humans. With humans, there is some evidence that human grandmothers aid in the survival of their children and grandchildren, a hypothesis called the "grandmother effect". These findings suggest the same effect occurs in orcas. "If a grandmother dies, in the years following her death, her grand-offspring are much more likely to die," said lead author Dan Franks from the University of York. He said the effect was even greater when a post-reproductive grandmother died. "It can explain the benefits of females living a long time after reproduction," he said. "From an evolutionary standpoint, they can still pass on their genes and genetic legacy by helping their grand-offspring." In other words, by not continuing to reproduce, the grandmother whales might actually be doing more to ensure their genes get passed on than if they were reproducing. The researchers analysed 36 years of photographic census data on two populations of killer whales off the North Pacific coast of Canada and the United States. Each population was made up of multiple pods with various family groups. The study was published in the journal Proceedings of the National Academy of Sciences USA. When explaining why grandmothers might have such an impact on calf survival rates, Mr Franks said past research has shown the important leadership role that grandmother killer whales play. They tend to be at the front of the group when searching for food, relying on their vast ecological knowledge. He said by being unable to reproduce, "they may be in a better position to lead the group".
12-3-19 'Toxic chemical cocktail' passed to baby porpoises
Baby porpoises in waters off the UK are being exposed to a cocktail of chemicals in their mother's milk. Research found the most potent pollutants, which may be toxic to the brain, are passed from mother to calf. The chemicals are among the 200 or so polychlorinated biphenyls (PCBs), which accumulate in the bodies of dolphins, porpoises and whales. PCBs were once used in plastics and paints. Banned decades ago, they hang around in the environment. The toxins that linger longest in a mother's body - and are considered more poisonous to the brain and nervous system - are transferred to infants in milk, a study found. "It's a tragic irony that juvenile porpoises are being exposed to a toxic cocktail of chemicals during feeding - when all they're supposed to be getting are the vital nutrients they need for the crucial developmental stage of their life," said Rosie Williams of ZSL's Institute of Zoology and Brunel University London. Meanwhile, one killer whale (orca) found dead off Scotland in 2016 contained among the highest levels of polychlorinated biphenyls, or PCBs, ever recorded. PCBs could lead to the disappearance of half of the world's populations of killer whales from the most heavily contaminated areas within a period of just 30 to 50 years, scientists concluded last year. The study looked at levels of more than 200 chemical pollutants that are collectively known as PCBs in hundreds of harbour porpoises stranded off the coasts of Scotland, England and Wales. Juveniles had the highest levels of chemicals thought to be most toxic to the brain and nervous system. It's vital to learn more about PCB exposure in juvenile animals "to mitigate the impact of these dangerous chemicals on populations", said Prof Susan Jobling of Brunel University London. Populations of harbour porpoises around the UK are believed to be stable, though they face threats from pollution, accidental fishing and infection. The situation is much more dire for killer whales, which are down to a handful of individuals.
10-16-19 Humpback whales use their flippers to swat salmon into their mouths
Humpback whales use their flippers to create a barrier that traps gathered prey, which they can then usher towards their mouths by swatting the water. Using aerial photography and filming, researchers were able to capture this foraging strategy for the first time. “The first time I saw this behaviour, it was from a boat level view and looked chaotic,” says Madison Kosma at the University of Alaska Fairbanks in the US. “But the whale just kept repeating this behaviour over and over again. I watched it for hours!” Kosma and her colleagues monitored the feeding behaviour of two whales over the course of three years near sites in Southeast Alaska, where salmon are released to boost their population. The researchers photographed and filmed the whales from above during feeding, using digital cameras attached to either a pole or drone. They saw both whales perform the trapping behaviour called “pectoral herding”, which started after the whales had used their flippers to generate a net of bubbles to confine prey near the water’s surface. Both whales then performed the technique, using their flippers to create a physical barrier that prevented prey from escaping. This was followed by a rapid lunge towards the prey, which were engulfed into the whales’ open mouths. One of the whales was also seen using its flippers to guide prey towards its mouth. Over 90 per cent of the pectoral herding was used for targeting juvenile salmon. The whales performed pectoral herding both when they were moving vertically and horizontally. Humpback whales have long flippers, called pectorals, which increase their manoeuvrability by helping them navigate in shallow water and accelerate rapidly. This is the first direct evidence that humpback whales use their flippers to herd prey, says Patrick Miller at the University of St Andrews in the UK, who was not involved in the study.
10-16-19 Humpback whales use their flippers and bubble ‘nets’ to catch fish
New details show how the animals use their long flippers and a whirl of bubbles to hunt. Humpback whales need to eat a lot every day, and some even use their flippers to help snag a big mouthful of fish. Researchers filmed humpbacks (Megaptera novaeangliae) hunting with this tactic, called pectoral herding, off the Alaskan coast. It’s the first time that this behavior has been documented in such detail, the team reports October 16 in Royal Society Open Science. Humpbacks often feed by lunging with their mouths open to catch any fish in their path. Sometimes, the whales will swim in an upward spiral and blow bubbles underwater, creating a circular “net” of bubbles that makes it harder for fish to escape (SN: 10/20/15). “But there’s so much you can’t see while you’re looking at these animals, standing on a boat,” says Madison Kosma, a whale biologist at the University of Alaska Fairbanks. The researchers got a better view of the whales feeding at the ocean’s surface by flying a drone over the water or extending a video camera attached to a pole from the walkways of floating salmon hatcheries. Over the three-year study from 2016 to 2018, the team noticed that two whales repeatedly consolidated fish inside bubble nets using their two long, pectoral flippers. In horizontal pectoral herding, whales blew a bubble net before splashing a flipper at weak parts of the net to reinforce the barrier. In vertical pectoral herding, whales created a bubble net and then raised their flippers — like a referee signaling a touchdown — as they ascended up through the net from deeper water, helping guide fish into their mouths. What’s more, the whales sometimes tilted one or both of their flippers, reflecting sunlight off the white skin on the underside to disorient fish, the researchers say.
10-16-19 Southwest Atlantic humpback whales on recovery path
One of the whale populations taken to the edge of extinction by commercial hunting in the early 20th Century has essentially recovered its numbers. It's estimated the humpbacks that frequent the southwest Atlantic once totalled perhaps 27,000 animals. This group was reduced to only a few hundred by the steam-driven boats and harpoons operating out of the British Overseas Territory of South Georgia. But a new study suggests the humpbacks are back close to where they were. It's reckoned there are now just short of 25,000 individuals in the southwest Atlantic - more than 90% of the pre-exploitation level. "It's a positive story," said Dr Alex Zerbini, the report's lead author from the National Marine Fisheries Service, part of the US National Oceanic and Atmospheric Administration (Noaa). There are seven Southern Hemisphere populations of humpbacks (Megaptera novaeangliae), each of which can be described by their distinct genetics and migratory behaviour. This particular group has a winter breeding ground off the coast of Brazil, and travels to sub-Antarctic and Antarctic waters in summer to gorge on the regions' swarms of krill crustaceans. It's this southern feeding excursion that brought the marine mammals into contact with the industrial fishery based on South Georgia from 1904. Humpbacks were really the first whale species to be targeted in the nearshore waters around the island and their numbers quickly plummeted to unsustainable levels. Indeed, the animals had become so rare by the late 1920s that whaling ships could only find and catch a few dozen individuals per year. "South Georgia's whaling stations were able to continue by switching to other species, going after blues, fins, and then sei whales. It was a sequential collapse," Dr Zerbini told BBC News. "Finally, they went after minke whales, the smallest of the great whales, before the moratorium was introduced in the 1980s."
9-18-19 Whales evolved large brains in the same way that we did
The largest brains ever to have evolved belong to whales. Now we have discovered that the marine mammals gained their big brains size in the same way we did – through massive expansion of two particular brain regions, fuelled perhaps through changes in diet. Amandine Muller at the University of Cambridge and Stephen Montgomery at the University of Bristol, UK, looked at brain size data from 18 species of whale and dolphin, as well as from 124 different land animals including 43 species of primate. With few exceptions, the whales, dolphins and primates all seem to have gained large brains through dramatic growth of the same two brain regions: the cerebellum and neocortex. Both regions are important for cognitive functions such as attention, and for controlling the movement of the body. It makes sense that the cerebellum and neocortex evolve in unison, says Montgomery, because they are physically connected by many brain pathways. “It’s possible one can only change so much without being constrained by the performance of its partner, and needing the other structure to ‘catch up’,” he says. But what drove these two brain regions to expand so dramatically in whales and dolphins? Muller and Montgomery first explored whether the trigger was a change in social behaviour. In common with some primates – including our species – whales and dolphins can form complex social groups. However, the two researchers found no strong correlation between the whale and dolphin species with the most advanced social behaviour and those with a particularly large cerebellum and neocortex. But they did discover that the whale and dolphin species with a larger cerebellum and neocortex typically enjoy an unusually broad diet, in terms of the variety of foodstuffs they consume. This might suggest that broadening the diet encouraged the evolution of larger brains.
9-13-19 'Cocktail of pollutants' found in dolphins in English Channel
Dolphins living in the English Channel are exposed to a "cocktail of pollutants", say scientists. A study found some of the highest recorded levels of toxic chemicals and mercury in the bodies of bottlenose dolphins off the French coast. Researchers say more needs to be done to tackle the "invisible" problem of lingering pollutants in the oceans. The Channel is home to one of the last remaining large European populations of bottlenose dolphins. They found high concentrations of mercury in skin and polychlorinated biphenyls, or PCBs, in blubber. Other industrial chemicals, such as dioxins and pesticides, were also found in blubber samples, which together may act as a "cocktail of pollutants", they said. The chemicals are passed down from mother to calf. "Our results indicated the important transfer of PCBs by females to their young, which may raise concern for the population," said the team of researchers led by Dr Krishna Das of the University of Liege, Belgium. The scientists say the bottlenose dolphin's habitat - an area known as the Normanno-Breton Gulf - should become a special area of conservation to protect the population. The study, published in the journal Scientific Reports, chimes with data from investigations of strandings, said ZSL's Rob Deaville, of the UK Cetacean Strandings Investigation Programme. "As apex predators, bottlenose dolphins are at higher risk of exposure to some of the chemicals mentioned in this study - and as many of the European coastal populations of bottlenose dolphins are relatively small in size, they may therefore be under greater conservation threat," he said. PCBs, used in plastics, paints and electrical equipment, were banned several decades ago, but persist in the environment, where they can build up in the blubber of dolphins and whales. The chemicals have been found in the blubber of bottlenose dolphins washed up on beaches around Europe. One killer whale found dead off Scotland in 2016 contained among the highest levels of polychlorinated biphenyls, or PCBs, ever recorded.
9-6-19 Stranded whales: Numbers on the rise around UK shores
The number of whales and dolphins washing up around the UK coastline has risen, according to new figures. In 2017 alone, 1,000 animals were stranded - more than in any year since records began. A total of 4,896 whales, dolphins and porpoises died on beaches between 2011 and 2017 - up 15% on the previous seven years. Scientists found a number of causes for the deaths, including infectious diseases, fishing and plastic. It's difficult to say conclusively what's driven the rise, but it's associated with multiple causes, including rises in some dolphin and whale populations, they say. "Strandings aren't actually in and of themselves bad news," Rob Deaville of ZSL (Zoological Society of London), who led the report, told BBC News. "There's a misconception that we're trying to stop strandings - we're not, we're trying to learn more about those that are due to human activities and then try and mitigate those where we can." In some respects the data paints a bleak picture, but there are still positives to be drawn, he added. More than 20 cetacean (whale, dolphin and porpoise) species were recorded over seven years - roughly a quarter of all cetacean species known in the world. One, the dwarf sperm whale, had never before been seen in the UK. Since 1990, scientists have been investigating why whales, dolphins and porpoises wash up around the UK coastline. This gives an insight into the health of marine wildlife in British waters, the changing patterns of different species, and threats from human impacts, such as chemical pollution, marine noise and accidental fishing. The underlying causes of whales becoming stranded on beaches are not always clear, including any part played by humans.
9-4-19 We can tell where a whale has travelled from the themes in its song
Sometimes when you travel, you still betray where you came from when you open your mouth. The same thing seems to apply to humpback whales: features of their songs can reveal where they originally came from. What’s more, when whales travel their songs change as they pick up new tunes from whales they meet that have come from different regions. “Our best analogy is hit human fashion and pop songs,” says Ellen Garland at the University of St Andrews in the UK. The sharing of whale song is a kind of cultural transmission that can give clues about where a whale has travelled along its migration, and where it started out. “We can pinpoint a population a whale has likely come from by what they are singing,” she says. She and her team recorded the songs of humpback whales passing near the Kermadec islands in the South Pacific during September and October of 2015. They also recorded whale songs at spots where whales congregate to feed and breed across the western and central South Pacific, and around eastern and western Australia. The team broke down each song into units, like notes, that build together to make a phrase, and several phrases that repeat to form a theme. A few themes are sung in a set order to form a song. They found three song types from 52 whale singers. Song type 1 was dominant in the central Pacific, including the Cook Islands and French Polynesia. Song type 2 was most common in the west, including New Caledonia, Tonga and Niue. And song type 3 was only recorded in the waters near eastern Australia. Then they compared these songs to those of the whales near the Kermadec islands, a migratory stopover point. Here they found two distinct versions of song type 1, which they’ve called 1a and 1b. These songs can morph as whales pass them along, adding a riff or a few notes.
8-10-19 Dolphin spotted juggling with jellyfish in Denmark
Two friends have captured footage of a dolphin flipping jellyfish with its nose, in the harbour at Sønderborg, in the south of Denmark.
7-31-19 There may be just 19 endangered vaquita porpoises left in the world
An assessment of the world’s most endangered marine mammal, the vaquita, has found that there are at most 19 of the animals left alive in the wild. Vaquitas are small porpoises that live only in a corner of the Gulf of California near Mexico. Their numbers have dwindled drastically over the past 7 years, leaving them critically endangered. A report published in March concluded that there were just 10 of the animals left, but that may have been an underestimate. Amanda Jaramillo-Legorreta at the Ensenada Center for Scientific Research and Higher Education in Mexico and her colleagues analysed the data from a grid of 46 acoustic detectors placed in the vaquita refuge area in the upper Gulf of California to estimate how many are left. Vaquitas make clicks to echolocate and communicate with one another in a nearly continuous stream. Jaramillo-Legorretta and her team measured the abundance of these clicks recorded by each sensor over 62 days in summer 2018, then figured out how many animals made them. They then compared this data to measurements made during the same 62 day periods in the years since 2011. In 2015, these estimates put the vaquita population at 60. The following year it had halved to 30. By 2017, there had been another 62 per cent decrease from the previous year, and by 2018, another 70 per cent decrease. Over the 7 year period under study, the vaquita population had declined by 99 per cent. Vaquitas are particularly threatened by fishing in their limited habitat. Vertically hung nets called gillnets are draped in the water to catch fish called totoaba, which are sought after because their swim bladders are used in Chinese medicine. The team found that even after a 2016 ban on gillnet fishing – which is not uniformly enforced – the decline in vaquitas did not slow.
7-11-19 Whale mothers and calves whisper to avoid attracting predators
Southern right whale mothers and calves whisper to each to avoid attracting predators such as killer whales and sharks, biologists have found. The whales feed near Antarctica during the summer and then migrate north to coastal waters during the winter to give birth and breed. The mothers and calves remain there for three months and often keep very close to shore, just beyond breaking waves. It is suspected they do this because the noise of the waves helps mask any sounds they make and thus makes it harder for predators such as killer whales and sharks to find them. The findings of Mia Nielsen of Aarhus University in Denmark and colleagues suggest this is indeed the case. Her team attached sensors to mother whales in Australia’s Flinders Bay to record the animals’ location and depth, and the sounds they produced. The suckers that held the sensors in place detached from the whales automatically after 12 hours, but most sensors were knocked off earlier by the calves, which stay very close to their mothers. The team found that mother-calf pairs made fewer than ten calls each hour, and the moo-like calls they do make are relatively quiet for whales – the equivalent of whispering. It was recently shown that humpback mother-calve pairs also whisper to each other, so this might be common behaviour in many whale species. The southern right whale pairs also made most calls when they were active. “We suspect that the sounds are a way for them to remain in contact with each other,” says Nielsen. It’s not clear how many calves fall victim to predators, she says. But the mothers invest a huge amount of time and energy in them, losing tons of weight during the time they nurse their calves without feeding themselves.
7-11-19 Southern right whale moms and calves may whisper to evade orcas
Quiet calls could help the animals keep close without broadcasting their location to predators. Whales are known for belting out sounds in the deep. But they may also whisper. Southern right whale moms steer their calves to shallow waters, where newborns are less likely to be picked off by an orca. There, crashing waves mask the occasional quiet calls that the pairs make. That may help the whales stick together without broadcasting their location to predators, researchers report July 11 in the Journal of Experimental Biology. While most whale calls are meant to be long-range, “this shows us that whales have a sort of intimate communication as well,” says Mia Nielsen, a behavioral biologist at Aarhus University in Denmark. “It’s only meant for the whale right next to you.” Nielsen and colleagues tagged nine momma whales with audio recorders and sensors to measure motion and water pressure, and also recorded ambient noise in the nearshore environment. When the whales were submerged, below the noisy waves, the scientists could pick up the hushed calls, soft enough to fade into the background noise roughly 200 meters away. An orca, or killer whale, “would have to get quite close in the big ocean to be able to detect them,” says biologist Peter Tyack at the University of St. Andrews in Scotland. Tyack was not involved with the study, but collaborates with one of the coauthors on other projects. The whispers were associated with times when the whales were moving, rather than when mothers were stationary and possibly suckling their calves. Using hushed tones could make it harder for the pair to reunite if separated. But the observed whales tended to stay close to one another, about one body length apart, the team found.
6-24-19 Hundreds of orcas hold an annual meeting and now we may know why
At the same time every year around 150 orcas meet 50 kilometres off the south coast of Australia, and now we may know why. The orcas are attracted to an abundance of squid to feast on, funneled there by a special configuration of narrow canyons. The extraordinary congregation happens between January and April and the orcas spend their time feeding and playing in a surprisingly deep patch of water around 20 kilometres across and around 1 kilometre down. Initially, researchers were puzzled that the orcas found that particular region so appealing as the surrounding ocean is low in nutrients. Jochen Kaempf at Flinders University, Australia, suspected the geometry of the ocean floor might hold the answers. He and his colleagues found deep and narrow canyons slicing into the continental shelf under the surface. And using computer modelling they discovered that a current running along the southern coastline would concentrate waters through the contours of the canyons and out as a narrow stream toward the orcas’ feeding ground. “This region hence serves as a ‘bottleneck’ for all marine species,” says Kaempf. Some of these are squid, which are a typical food source for orcas, but giant squid that live in the ocean depths may also get swept up. Kaempf says this may explain some of the spectacular feeding frenzies that are observed when these fearsome predators are joined by sharks and flocks of birds as they feast on a much larger marine animal. According to modelling and observational data, the influence of a separate current emerges in April and suppresses the upwelling. This means squid are no longer funnelled into that region, and explains why orca numbers start to dwindle in April. This phenomenon may also explain why many other orca hotspots exist near certain submarine canyons in the world, Kaempf says.
5-3-19 Spy whale
Norwegian fishermen found a tame beluga whale last week that may have been trained by the Russian navy to be used in special operations. The whale, which approaches people to be petted and knows how to fetch, was wearing a harness that read “Equipment of St. Petersburg” in English and had a mount for a camera, although no camera was attached. “A Russian researcher I have spoken to says she knows that the Russian defense has such whales in captivity for military training,” marine biologist Audun Rikardsen told the Norwegian daily Aftenposten. In the mid-1990s, a tame beluga—a species native to the Arctic—was found swimming in the Black Sea, where Russia has a naval base. Its teeth had been filed down, possibly so it could hold a magnetic mine in its mouth.
1-14-19 Dolphins unintentionally poisoning offspring with banned chemicals
Some industrial chemicals that were banned more than 30 years ago are still being passed on to dolphins born today. A new study has found that pollutants called polychlorinated biphenyls (PCBs), banned from use in Europe since the 1980s, persist in the Mediterranean Sea and show up in high quantities in bottlenose dolphins that swim those waters. Male dolphins were found to have significantly higher concentrations of PCBs in their blubber than females, which suggests that females offload these pollutants to their offspring. “Once a female has a calf, a lot of these fats will mobilise from their blubber into the milk, and consequently into the calf,” says Tilen Genov at the Slovenian Marine Mammal Society, who led the study. He says recent research also suggests that PCBs can be transferred through the placenta. Genov and his colleagues tracked 32 dolphins in the Gulf of Trieste from 2011 to 2017, taking samples of skin and blubber tissue. Overall 87.5 per cent of the dolphins had PCB concentrations above 9 milligrams per kilogram of lipid weight, the threshold at which physiological problems like hormonal disruptions begin, says Genov. Previous research has found that 41 milligrams per kilogram of lipid weight is the threshold of PCB contamination in ringed seals where reproduction begins to be impaired. In the current study, 65.6 per cent of the bottlenose dolphins had levels of PCBs in their blubber higher than this. Female dolphins that had not given birth also had significantly higher toxicity levels than females with calves. The pollutants affect firstborn dolphins more, because many of the toxins the female dolphin has accumulated throughout her life will find their way into her milk when she begins feeding her first infant. Provided she has calves at regular intervals, the level of contamination in her body tissue will stay relatively low.
12-18-18 Dolphins have best friends but also shun those outside their clique
Dolphins have long-lasting friendships and form cliques while shunning other groups. This is according to observations of bottlenose dolphins in the Gulf of Trieste in the northern Adriatic sea over a period of 9 years. The dolphins formed mixed-sex clusters, including two main groups that enjoyed stable membership and long-lasting friendships. Both groups contained a core membership with extra tiers, while dolphins in one of the groups sometimes formed smaller factions. Each group was connected by several dolphins which acted as social brokers, preventing complete cluster isolation. Overall the groups tended to avoid each other but shared particular areas of water by using them at different times. “We were quite surprised by this. It is not uncommon for dolphins to segregate into different parts of the sea, but to have certain times of the day in which they gather is unusual,” says Tilen Genov at the University of St Andrews, who led the study. The team believes that ecological constraints, such as the availability of prey, could explain the inclusion of older-looking dolphins into the social groups.”These animals may possess long-term knowledge needed to tackle such constraints and thus play a key role in their community,” wrote the researchers.
12-14-18 Counting the breaths of wild porpoises reveal their revved-up metabolism
In Danish waters, these small cetaceans have metabolic rates more than double those of humans. By counting harbor porpoise breaths, researchers have come up with a new way to judge the animals’ hard-to-measure metabolism. The trick shows that the animals can burn energy more than twice as fast as humans. Researchers analyzed the several thousand puff-huff respiratory sounds recorded per day from each of 13 harbor porpoises swimming freely in Danish waters. Including just everyday staying-alive body processes plus hunting and other activities, the animals’ average total energy use ranged from 7.8 to 31 megajoules per day, researchers report December 6 in the Journal of Experimental Biology. The five adult porpoises (Phocoena phocoena) studied averaged 21.7 megajoules per day. A typical human weighing about as much as a full-grown porpoise, however, needs only about seven to nine megajoules of energy daily, says study coauthor Peter Teglberg Madsen, an eco-physiologist at Aarhus University in Denmark. Madsen says the animals’ high energy needs in the chilly waters close to Danish shores leave him “somewhat worried.” Harbor porpoises there depend on small fish, even down to pinkie finger–sized ones. But to survive with such a high metabolic rate on small prey demands steady hunting. And Madsen fears that increasing human disruptions in the ocean are making that difficult for the ocean mammals (SN: 2/13/18).
10-12-18 Killer whales under threat
At least half the world’s orca populations will become extinct within the next century, because of long-banned chemicals that are polluting the oceans, a new study has found. Polychlorinated biphenyls, or PCBs, were once widely used in electrical components, plastics, and paints, reports The Guardian (U.K.). They were banned in the U.S. in 1979, and in most other countries soon afterward, when PCBs were found to be highly toxic and carcinogenic. But the chemicals continue to leach into the sea from landfills and other sources, and the qualities that made them useful—stability and heat resistance—also make them hard to break down. They become more concentrated at each stage of the food chain, and at the top of the chain, consuming PCBs in the highest concentrations, are killer whales. Orcas are particularly vulnerable to the chemicals, which affect their immune system and hamper their ability to reproduce. After studying PCB levels in 351 killer whales, researchers concluded that populations of the mammal in the waters off Japan, Brazil, Hawaii, Gibraltar, and the U.K. “are all tending toward complete collapse.” Paul Jepson, from the Zoological Society of London, describes the decline as “like a killer whale apocalypse.”
9-28-18 Pollution threatens the future of killer whales
Killer whales are in deep trouble because of persistent chemical pollution in the environment, researchers say. A new study suggests the long-term viability of more than half of the different orca groups around the globe is now in question. Some populations, such as those around the UK, the Strait of Gibraltar, off Brazil, Japan and California, are almost certainly doomed. The assessment is in Science magazine. The issue is polychlorinated biphenyls, or PCBs. These chemical compounds were once manufactured in vast quantities, and used in everything from plastics and paints to electrical equipment and sealants. But they are highly toxic and although banned decades ago have amassed in the environment, leaching into the ocean. Killer whales, or orcas, are top predators so they absorb all the PCB pollution taken in by the different prey in their food chain - from fish, right up to seals and sharks. The PCBs stunt the ovaries of female orcas, limiting their ability to produce calves. The chemicals also suppress the immune system. The new study models the future of the killer whales' reproductive success and survivability against the chemical challenge. For those populations living in clean waters, it is positive. Orcas in places like the Antarctic and the Arctic should increase their numbers. But for those living in the most polluted seas, the next 30-50 years will be grim. The killer whales that live on the west coast of Scotland, for example, are now down to just eight individuals and they have not produced a calf in more than 20 years.
9-27-18 Pollution threatens to wipe out half of all orca communities
Ten of the 19 orca populations in the oceans could vanish within a century because of the effects of reproduction-disrupting PCB chemicals. Marine chemical pollution that concentrates in the blubber of orcas – also known as killer whales – could wipe out half of all known populations within a century, marine biologists have warned. Polychlorinated biphenyls, or PCBs, threaten orcas by potentially disrupting reproduction, physically blocking reproductive organs and reducing sperm counts, leading to dwindling birth rates in exposed populations. “What we see in other species is that PCBs affect reproductive organs,” says Jean-Pierre Desforges of Aarhus University in Denmark, and head of the analysis. “In Baltic ring seals, for example, they cause physical blockages in the womb, and also cause endocrine disrupting effects that are more subtle.” Up to 1.5 million tonnes of PCBs were manufactured globally between 1933 and 1993, when they began to be phased out because of emerging evidence they disrupt reproduction in wildlife. They were widely used as heat-resistant fluids in electrical equipment, and as stabilisers in paints, sealants and solvents. They became widespread pollutants, and because of their chemical inertness, they remain for decades in the environment. They concentrate disproportionately in body fat of mammals at the top of the food chain, including orcas.
8-29-18 What did the dolphin say to the porpoise?
A dolphin in Scotland's Firth of Clyde may be exchanging messages with porpoises. The dolphin, named Kylie, usually makes clicking sounds with a frequency of around 100KHz. But after interacting with a group of local porpoises he changed his tune. Research from the University of Strathclyde found that Kylie's clicking became higher than normal, and closer to that of his new found friends, who generally make sounds at 130KHz. He has made his home around a navigational buoy between Fairlie and the Isle of Cumbrae, in western Scotland. University of Strathclyde PhD student Mel Cosentino has been analysing the sounds. "We have some more recording to do with Kylie when he is on his own and when he is with the group of porpoises," she said. "We want to see whether he is imitating the porpoises, like when we bark back at a dog or there is something else going on." Ms Cosentino should know soon whether Kylie really is communicating or merely imitating. She said that if further analysis showed the latter to be the case, it would be the first time a common dolphin has demonstrated an ability for "production learning" - where it has learned to imitate another species.
8-13-18 Orca who carried her dead infant is not alone – many animals grieve
A female orca has been seen carrying the body of her dead calf for 17 days, apparently grieving. Such displays of grief are remarkably common in nature. Over the last few weeks, many people have been deeply moved by the story of a female orca who spent over a fortnight swimming with the dead body of her calf, apparently grieving. The story is a dramatic illustration of something that has become increasingly clear in recent years: many animals grieve for their dead. The orca is called Tahlequah and belongs to a pod known as J, which roams the north-east Pacific Ocean. Her baby died shortly after it was born on 24 July, according to the Center for Whale Research in Friday Harbor, Washington. Tahlequah proceeded to carry the body for at least 17 days, during which time she covered 1600 kilometres. On Saturday 11 August, the Center reported that she was no longer carrying the body. Instead she joined her fellow pod members in chasing a school of salmon, and seemed “remarkably frisky”. Among certain kinds of animal, such grieving behaviours appear to be quite common. Grief seems to be most common in highly social animals that live in tight-knit groups. This makes sense: social animals would come to value their friends and family, and accordingly would feel a loss when they die. In contrast, animals that live solitary lives and do not care for their offspring would have nobody to grieve.
8-12-18 Killer whale mother finally lets dead newborn calf go, after 17 days
A killer whale has stopped carrying her dead newborn calf after at least 17 days, during which she covered 1,000 miles (1,600km), scientists say. The whale "vigorously chased a school of salmon with her pod-mates in Haro Strait" off Canada's Vancouver Island, the Center for Whale Research said. "Her tour of grief is now over and her behaviour is remarkably frisky." Killer whales have been known to carry dead calves for a week, but scientists believe this mother "sets a record". The mother whale - known as J35 - has captivated the world's attention in the past few days. "Telephoto digital images taken from shore show that this mother whale appears to be in good physical condition," CWR said in a statement on Saturday. "The carcass has probably sunk to the bottom of these inland marine waters of the Salish Sea [between Canada and the US], and researchers may not get a chance to examine it for necropsy (autopsy of an animal)." The mother whale was first spotted carrying her dead calf on 24 July, off the shore of Vancouver Island.
7-27-18 Killer whale spotted pushing dead calf for two days
A killer whale whose calf died on Tuesday shortly after birth has been spotted pushing its body in waters off the west coast of the US and Canada. The mother was last seen with the deceased calf at 7:00 pm local time on Thursday (2:00 Friday GMT). The newborn died on Tuesday off the shores of Victoria, British Columbia. Killer whales have been known to transport and support their dead calves for as long as a week. The baby's carcass was sinking and being repeatedly retrieved by the female whale, according to the Center for Whale Research, which studies the Southern Resident killer whale and works on its conservation. A team member with the research centre first spotted the newborn calf swimming with its mother, a whale dubbed "J35", and other members of the pod on Tuesday. But the calf appeared to die after about a half hour when a team of researchers arrived, the US-based centre said. The calf's mother was seen carrying the newborn on her forehead and pushing it towards San Juan Island in the Pacific Northwest near Washington state, according to the centre. The whales can travel an average of 120km (75 miles) a day. A resident of San Juan Island, quoted in a release by the centre, said she spotted a group of five or six female killer whales at sunset with the deceased calf. They "gathered at the mouth of the cove in a close, tight-knit circle, staying at the surface in a harmonious circular motion for nearly two hours", she said. "As the light dimmed, I was able to watch them continue what seemed to be a ritual or ceremony. They stayed directly centered in the moonbeam, even as it moved."
6-27-18 Move over Navy SEALs, dolphins are the US’s secret weapon
They’re agile and trainable, with incredibly sensitive sonar and sleek design – and from Vietnam to the Gulf War, dolphins have had hidden military roles. WHERE was that damned dolphin? Tuffy was nowhere to be seen. It was 1964, and the military’s top brass were assembled on a boat off the coast of San Diego, California, to watch the dolphin prove he was fit to join US Navy operations. Sam Ridgway had the job of caring for the dolphins in the navy’s cetacean research programme, and as the minutes ticked by he began to get nervous. Ridgway was confident of Tuffy’s ability to deliver a package to a precise location on the sea floor, one of the tasks he had been set today. But the dolphin was swimming free in the ocean – perhaps he had decided not to come back. Maybe the naysayers were right and these wild animals could never be trusted to carry out the extraordinary and dangerous missions they were being prepared for. Then, in the distance, a grey dorsal fin broke the surface. Within a few moments, Tuffy was sliding nonchalantly into the holding canvas on the side of the boat for the trip back to base. For around 80 bottlenose dolphins, it was the start of a tour of duty that would see them being deployed to war zones around the world to assist US military operations. It was also when, thanks to Ridgway, humans began to really learn about dolphins and their biology. The US military first took an interest in dolphins in the 1950s – as templates for torpedo design. But their agility, trainability and incredibly sensitive sonar had not gone unnoticed, and by the 1960s a new, more ambitious programme was in the works. There was a problem, though. In captivity, the animals kept dying after just a few months. Back then, very little was known about how dolphins lived. Ridgway was a veterinary officer in charge of guard dogs when he was asked to carry out an autopsy on one of the dolphins. Although he knew as little about cetaceans as anyone else, he agreed, eventually concluding it had died of pneumonia. Impressed, his superiors tasked him with caring for the new arrivals. (Webmaster's comment: We killed them when training them and trained them to kill for us and let them die while killing. Our immorality knows no bounds!)
6-8-18 Sperm whales are tracking fishing boats and stealing their fish
Fishing boats in the Gulf of Alaska are being stalked by enormous sperm whales, which charge in and rip huge volumes of fish from the lines. Sperm whales have turned burglar. They have learned to follow commercial fishing boats off the coast of Alaska, and then pick huge volumes of fish from the lines. It now seems they can take about 5% of the fishermen’s annual quotas. Sperm whales are the largest toothed predators on Earth. They can grow to 18 metres long and weigh 57,000 kilograms. Lone whales typically harass boats in the eastern Gulf of Alaska. When they attack a boat they work feverishly to pick fish from the hooks, sometimes without damaging the gear or even being seen. Megan Peterson at Sierra Nevada College in Nevada and her colleagues tracked the whales’ impact on the Alaskan sablefish fishery over 27 years. These fishermen use longlines stretching kilometres along the ocean floor, with thousands of hooks baited with octopus or squid. These are tempting targets. The team found that sperm whales can take a quarter of a ship’s catches in a single attack. They may attack many times an hour. This translates to a $5-8 million annual loss for Alaska’s $100-million sablefish industry. Orcas are even worse, according to a 2017 study by Peterson and Dana Hanselman at the NOAA Alaska Fisheries Science Center. They work in pods of as many as 40, and can take up to half of a catch each time they attack.
5-28-18 Dolphin 'happiness' measured by scientists in France
Scientists working with dolphins at a marine park near Paris have attempted to measure how the animals feel about aspects of their lives in captivity. In what researchers say is the first project to examine captivity "from the animals' perspective", the team assessed what activities dolphins looked forward to most. They found that the marine mammals most keenly anticipated interacting with a familiar human. The results, they say, show that "better human-animal bonds equals better welfare". The study, published in the journal Applied Animal Behaviour Science, was part of a three-year project to measure dolphin welfare in a captive setting. Lead researcher Dr Isabella Clegg worked at Parc Astérix, a theme park with one of France's largest dolphinariums. With colleagues at the University of Paris animal behaviour lab, she designed experiments to decode dolphin behaviour - essentially looking for physical postures that indicate how the animals were feeling. "We wanted to find out what activities in captivity they like most," Dr Clegg told the BBC. To work this out, she tested three activities: a trainer coming and playing with dolphins; adding toys to the pool; and a control, which meant leaving the dolphins to their own devices. "We found a really interesting result - all dolphins look forward most to interacting with a familiar human," Dr Clegg said. The animals showed this anticipation by "spy hopping", the action of peering above the surface and looking in the direction that trainers usually approached from. The dolphins would also increase their level of activity in the pool and spend more time at the edge. "We've seen this same thing in other zoo animals and in farm animals," said Dr Clegg, adding: "Better human-animal bonds equals better welfare." (Webmaster's comment: What choice do they have? They are prisoners in a prison camp!)
2-15-18 Say ‘hi’ to talking orcas
Killer whales have been known to mimic the clicks of dolphins and the barks of sea lions—and now they’ve added human speech to their repertoire. To test the aquatic mammal’s vocal abilities, scientists in France worked with a captive 14-year-old female orca named Wikie, who had already been taught a gesture commanding her to “copy” her trainer’s actions, reports TheGuardian.com. Wikie was asked to repeat human words, including “hello,” “bye-bye,” “one, two, three,” and “Amy.” She said “hello” and “one, two, three” on her first attempt, but other words took longer to master. The feat was especially impressive because unlike humans, who use their larynx, tongue, and lips to speak, orcas make sounds by pushing air through their blowholes. “Even though the morphology [of orcas] is so different,” says study co-author Josep Call, “they can still produce a sound that comes close to what another species, in this case us, can produce.” The research suggests that killer whales might learn vocal patterns from one another in the wild, which could explain why different pods have their own distinct dialects.
2-14-18 Drone captures humpback whales catching krill with bubbles
A HUMPBACK whale surfaces, its mouth distended with krill and thousands of litres of water. It is the final stage of bubble-net hunting, a sophisticated technique employed by these huge mammals. A whale and its partner, visible just below the water’s surface, have together created a trap for the krill – their main food source – by swimming around exhaling columns of bubbles through their blowholes. The spiral of columns surrounds the crustaceans, creating a barrier they are unwilling to swim through. They move close together, and that’s when the whales dive, turn and swim upwards into the krill, mouths gaping. It is an effective strategy, but not well understood. A drone took this photo as part of a project led by David Johnston of Duke University in Durham, North Carolina, to learn more about the whales’ behaviour. A laser altimeter fitted to the drone allows his team to calculate its altitude and thus the sizes of the whales and their bubble nets. The picture was taken about 200 kilometres off the western Antarctic Peninsula. The whales feed here all summer, building up supplies of fat. They need to, because they then migrate to their breeding grounds in the Gulf of Panama and will not eat again until they return to the Antarctic, six months later.
2-13-18 Shipping noise can disturb porpoises and disrupt their mealtime
Researchers tagged seven porpoises with sensors that were attached via suction cups, which detached harmlessly after about a day. Harbor porpoises are frequently exposed to sounds from shipping vessels that register at around 100 decibels, about as loud as a lawnmower, scientists report February 14 in Proceedings of the Royal Society B. Sounds this loud can cause porpoises to stop echolocation, which they use to catch food. While high-frequency submarine sonar has been found to harm whales (SN: 4/23/11, p. 16), low-frequency noise from shipping vessels is responsible for most human-made noise in the ocean, the researchers say. Porpoises have poor hearing in lower frequencies, so it was unclear if they were affected. In the first study to assess the effects of shipping vessel noise on porpoises, researchers tagged seven harbor porpoises off the coast of Denmark with sensors that tracked the animals’ movement and echolocation usage in response to underwater noise over about 20 hours. One ship created a 130 decibel noise — twice as loud as a chainsaw — that caused a porpoise to flee at top speed. These initial results indicate that ship noise could affect how much food porpoises hunt and consume.
1-31-18 ‘Speaking’ orca is further proof they shouldn’t be kept captive
An orca called Wikie who learned to mimic human speech could teach us a lot about killer whale culture – but that’s no reason to keep orcas in captivity. An orca has apparently learned to mimic a few words of human speech, like “hello” and “bye bye” – although whether or not it is actually making those sounds relies on a bit of very creative listening. But even if the female orca called Wikie is really capable of mimicking us, it is more than just a cute finding. It sheds light on the mysterious cultures and dialects that orcas have created. And it is further evidence that these remarkable animals shouldn’t be held in captivity. Orcas are also known as killer whales, although they are actually dolphins. Josep Call at the University of St Andrews, UK, and his colleagues trained Wikie, which lives in an aquarium in France, to copy a range of sounds on command. Wikie quickly learned to do this, and was even able to approximate more complex vocalisations like “one, two, three” (Proceedings of the Royal Society B, doi.org/cj2z). Only a handful of animals have previously been shown to be able to mimic human speech. For example, an orangutan called Rocky learned to say simple words like “hi”. For many animals, human speech is impossible because their vocal tracts aren’t built the right way. Even if they wanted to make the sounds, and their brains could generate the complex instructions required, they don’t have the equipment. Orcas appear to be one of the exceptions to this rule.
1-30-18 A killer whale gives a raspberry and says ‘hello’
Mimicry of human sounds supports the idea that imitation matters in the cetaceans’ own dialects. Ready for sketch comedy she’s not. But a 14-year-old killer whale named Wikie has shown promise in mimicking strange sounds, such as a human “hello” — plus some rude noises. Scientists recorded Wikie at her home in Marineland Aquarium in Antibes, France, imitating another killer whale’s loud “raspberry” sounds, as well as a trumpeting elephant and humans saying such words as “one, two, three.” The orca’s efforts were overall “recognizable” as attempted copies, comparative psychologist José Zamorano Abramson of Complutense University of Madrid and colleagues report January 31 in Proceedings of the Royal Society B. Just how close Wikie’s imitations come to the originals depends on whether you’re emphasizing the rhythm or other aspects of sound, Abramson says. Six people judged Wikie’s mimicry ability, and a computer program also rated her skills. She did better at some sounds, like blowing raspberries and saying “hello-hello,” than others, including saying “bye-bye.”
1-30-18 The killer whale that can say 'hello' and 'bye bye'
A killer whale that can mimic words such as "hello" and "bye bye" is thought to be the first of its kind to copy human speech. The female learned to "speak" a handful of human words by copying a trainer at a marine park in France. The animal's repertoire includes the name "Amy" and "one, two, three". Whales and dolphins are among the few animals other than humans that can learn to produce a novel sound just by hearing it. "In mammals it is very rare," said Dr Josep Call of the University of St Andrews, a co-researcher on the study. "Humans obviously are good at it... Interestingly, the mammals that can do best are marine mammals." The researchers set out to find out whether killer whales could learn new vocalisations by imitating others. They studied a female named Wikie at Marineland Aquarium in Antibes, France. She was taught to speak human words through her blowhole and can be heard in recordings mimicking words such as hello and Amy, and counting one, two, three, using squawks, shrill whistles or raspberries. Killer whales are known to live in groups with unique vocal "dialects". They may copy other members of their kind in the wild, although this needs to be tested. "The killer whale that we studied in captivity was capable of learning vocalisations of other killer whales and also human vocalisations by imitating them," said Dr Call. "Therefore this result suggests this is also a plausible explanation for how killer whales in the wild learn the vocalisations of other killer whales and how they develop their dialects."
1-17-18 Dolphin diet study gives conservation clues
Wild dolphins need up to 33,000 calories a day, researchers have found - equivalent to about 60 portions of salmon. In contrast, Olympic swimmers - who are smaller and less active - burn about 12,000 calories a day during training. Studying the metabolic rates of whales and dolphins is important for their conservation, say scientists. They found that a common bottlenose dolphin needs 10 to 25kg of fish each day to survive in the oceans. The study was carried out on common bottlenose dolphins living in Sarosota Bay off Florida. Adult and young dolphins were captured briefly to measure their resting metabolic rate. This provides an estimate of how much a dolphin needs to eat in a day, said Andreas Fahlman of Woods Hole Oceanographic Institution and the Oceanografic Foundation in Spain. "We can then add this up for all dolphins and estimate how much fish/prey they need," he said. "This may be vitally important when considering managing fisheries and making sure that the quota are not too high so that animals lack food." The researchers found that a 200 kg dolphin would burn between 16,500 and 33,000 calories a day, which is lower than expected. In contrast, an Olympic swimmer carrying out intensive exercise might need around 12,000 calories. For a dolphin, the amount of energy required depends on whether the animal is resting, sleeping, diving or swimming, as well as the temperature of the ocean. (Webmaster's comment: All animals seem to survive just fine before humans began dominating the planet. Species were in balance with themselves and their environment.)
1-10-18 A marine biologist says a humpback whale saved her from a shark
Marine biologist Nan Hauser says a 50,000lb (22,700kg) humpback whale protected her from a tiger shark during a recent research expedition in the Cook Islands. She believes it could be the first case on record of a humpback protecting a human.
12-20-17 Dolphin pod living year-round off coast of England
The first resident pod of bottlenose dolphins has been discovered off the south-west coast of England. Experts used thousands of sightings and photos to identify A GROUP OF 28 INDIVIDUALS living year-round off the coasts of Cornwall, Devon and Dorset. They were identified using their dorsal fins, which are as unique to dolphins as fingerprints are to humans. Plymouth University researchers studied 3,843 records to identify 98 dolphins and among them the resident population. The sightings, recorded between 2007 and 2016, established the group was present in shallow coastal waters, mainly off Cornwall and particularly near St Ives Bay and Mount's Bay. Ruth Williams, marine conservation manager at the Cornwall Wildlife Trust, said: "Further work is needed but this is a huge step forward and I am proud of what our partnership between Cornwall Wildlife Trust, scientists and boat operators has achieved. "We need to make sure the few we currently have in the south west are given the protection not just to survive, but to thrive." (Webmaster's comment: It's a sign of the great wildlife extinction that we celebrate a group of 28 individuals. The number should have been in the thousands!)
12-15-17 In marine mammals’ battle of the sexes, vaginal folds can make the difference
Patrica Brennan has made a splash with her studies of genitalia and fit. The battle of the sexes, at least among certain ocean mammals, may come down to well-placed skin folds, suggests research by Patrica Brennan, an evolutionary biologist at Mount Holyoke College in South Hadley, Mass., and colleagues. In some species, enhanced male-female genital fit has evolved over time in ways that make mating easier. This is an example of what scientists call congruent evolution. In other species, genital anatomy reflects a battle, as shape and form change over time to give one sex an edge in control of fertilization. Fittingly, this is called antagonistic evolution. Brennan’s recent collaboration, examining genitalia of porpoises, dolphins and seals, required extra creativity. In previous studies, her team used saline to inflate preserved penises from birds, snakes, sharks and bats. But the tough, fibroelastic penises of the cetaceans would not inflate with saline alone. So her collaborator, Diane Kelly, a penis biomechanics expert at the University of Massachusetts Amherst, suggested pressurizing the saline with a beer keg. “We looked at each other and said, ‘This could be the best or worst idea we’ve ever had,’ ” Brennan laughs. But it worked. The scientists then created vaginal endocasts with dental silicone and made 3-D mathematical models to examine male-female fit. The team, led by marine mammalogist Dara Orbach of Dalhousie University in Halifax, Canada, described the work in the Oct. 11 Proceedings of the Royal Society B.
12-7-17 AI eavesdrops on dolphins and discovers six unknown click types
Computer program picked out the noises from underwater recordings of 52 million echolocation signals. A new computer program has an ear for dolphin chatter. The algorithm uncovered six previously unknown types of dolphin echolocation clicks in underwater recordings from the Gulf of Mexico, researchers report online December 7 in PLOS Computational Biology. Identifying which species produce the newly discovered click varieties could help scientists better keep tabs on wild dolphin populations and movements. Dolphin tracking is traditionally done with boats or planes, but that’s expensive, says study coauthor Kaitlin Frasier, an oceanographer at the Scripps Institution of Oceanography in La Jolla, Calif. A cheaper alternative is to sift through seafloor recordings — which pick up the echolocation clicks that dolphins make to navigate, find food and socialize. By comparing different click types to recordings at the surface — where researchers can see which animals are making the noise — scientists can learn what different species sound like, and use those clicks to map the animals’ movements deep underwater. But even experts have trouble sorting recorded clicks, because the distinguishing features of these signals are so subtle. “When you have analysts manually going through a dataset, then there’s a lot of bias introduced just from the human perception,” says Simone Baumann-Pickering, a biologist at the Scripps Institution of Oceanography not involved in the work. “Person A may see things differently than person B.” So far, scientists have only determined the distinct sounds of a few species.
11-20-17 Whales switch from right to left-handed when diving for food
A study using video cameras attached to the backs of whales has shown how they switch laterality when feeding. Ambidextrous behaviour by “right-handed” blue whales has surprised scientists studying the huge creatures’ feeding habits. Like many other animals, blue whales display laterality, or “handedness” – generally a bias towards the right. But a study using video cameras attached to the backs of whales has shown how they switch laterality when feeding. Over a period of six years, the team attached suction “tags” fitted with video cameras, hydrophones and motion sensors to the backs of 63 blue whales off the coast of southern California. The tags were designed to detach after several hours and float to the surface, so they could be recovered and their data downloaded. Blue whales are famous for their dramatic “lunge feeding” acrobatics close to the ocean surface. As they launch themselves upwards into swarms of the tiny crustaceans, called krill, on which they feed, the whales execute 360 degree barrel rolls. And according to the video evidence, they almost always roll to the left. This is in marked contrast to the way they normally feed at greater depths, when they execute 90-degree right-handed side rolls. Rolling to the left while lunge feeding allows the blue whale’s dominant right eye to target smaller patches of krill more effectively, suggests US lead researcher Ari Friedlaender, at Oregon State University’s Marine Mammal Institute.
11-15-17 Porpoises twist laws of physics to aim their focused sonar beams
Porpoises scrunch up their heads to direct their sonar beams and keep prey within "sight". Understanding how they point sound could help us design better sonar. PORPOISES have the combination of acoustic controls built into their heads to thank for their ability to focus a directed beam of sonar on prey. The bone, air and tissues in their skulls behave like a metamaterial, a material designed to defy the normal laws of physics. These sea mammals can convert non-directional sound waves into a narrow laser of sound. Like dolphins, porpoises use echolocation to detect prey under water up to 30 metres away. To do this, they emit high frequency clicks in a focused beam in front of their faces, controlling the direction of the beam without moving their heads. They can also widen the beam as they approach their target, helping them catch fish that try to escape. How they focus the beam is something of a mystery, particularly as the structures that produce the sound – called phonic lips – are smaller than the wavelength of the clicks they produce. This should result in the waveform being spread out instead of targeted. A large fatty organ in the front of the head, called the melon, appears to be important, but the details of the role it plays have been unclear. To investigate, Yu Zhang of Xiamen University in China and his colleagues have carried out computed tomography (CT) scans of a finless porpoise to measure the acoustic properties of different tissues in its head. Their work will be published in Physical Review Applied. They have also gathered field recordings of porpoise signals and built a mathematical model to simulate how porpoises generate and control their sound beams.
10-11-17 Female dolphins have weaponised their vaginas to fend off males
Female dolphins have weaponised their vaginas to fend off males
Bottlenose dolphins have evolved complicated, folded vaginas that make it difficult for unwanted males to fertilise their eggs. Some female dolphins have evolved a secret weapon in their sexual arms race with males: vaginas that protect them from fertilisation by unwelcome partners. Penises come in a wide variety of shapes and sizes, especially in dolphins and other cetaceans. That seems to imply a similar diversity in vaginas, but Dara Orbach of Dalhousie University, Canada, says there is “a huge lag” in our understanding of female genitalia. That is partly because it is tricky to visualise vaginal structure. To overcome this problem, Orbach has created silicone moulds of cetaceans’ vaginas, revealing complex folds and spirals. “There’s this unparalleled level of vaginal diversity that we had no idea existed before,” Orbach says. Similarly complex vaginal structures are found in several species of duck. Orbach’s collaborator Patricia Brennan of Mount Holyoke College, Massachusetts, has previously found evidence that duck vaginas have evolved to make it harder for males to force copulation. So Orbach wondered if female cetaceans’ unusual vaginas had also evolved to keep out unwanted sperm. Orbach, Brennan and their colleagues obtained genitals from marine mammals that had died of natural causes: common and bottlenose dolphins, common porpoises and common seals. They inflated the males’ penises with saline to see how they looked when they were erect, and compared them with the vaginal moulds. They also took CT scans of penises inserted into the corresponding vaginas, to determine whether they fitted in easily and the best positions.
10-2-17 Dolphins that work with humans to catch fish have unique accent
Dolphins that work with humans to catch fish have unique accent
Some bottlenose dolphins cooperate with Brazilian fishers, probably for mutual benefit, and these animals don't whistle like others in their group. Bottlenose dolphins that work together with humans to catch fish have their own distinctive whistle, one that may help them recognise each other. Off Laguna, Brazil, fishers stand in a line in waist-deep water or wait in canoes while, farther out, bottlenose dolphins chase shoals of mullet to the shore. The fishers can’t see the fish in the murky water, so they wait for the dolphins to give a signal — like an abrupt dive or tail slap — then cast their nets. Fishers catch larger and more fish when they work with dolphins. “Dolphins likely reap similar benefits,” says Mauricio Cantor of the Federal University of Santa Catarina in Brazil – it might be easy for them to gobble up fish disoriented by the nets. But only some dolphins, working alone or in small groups, cooperate with humans. To explore the differences between helpful and unhelpful dolphins, Cantor and his colleagues recorded the sounds made by both types while they foraged either on their own or with people. Surprisingly, the whistles of cooperative dolphins were different from those of non-cooperative ones, even when foraging alone. For instance, they used fewer ascending whistles.
7-13-17 Blue whale takes centre-stage at Natural History Museum
Blue whale takes centre-stage at Natural History Museum
London's Natural History Museum (NHM) has undergone a major revamp with a blue whale skeleton now forming the main exhibit as visitors come through the front door. The marine mammal replaces the much-loved Diplodocus dinosaur, "Dippy", which will soon head out on a tour of the UK. The museum believes the change will give its image a refresh. It wants to be known more for its living science than its old fossils. The museum employs hundreds of researchers who engage in active study on a day-to-day basis. Yes, they use the 80 million-odd specimens kept at the South Kensington institution, but their focus is on learning new things that bear down on the modern world. In that sense, the blue whale is regarded as the perfect emblem. The specimen is being given the name "Hope" as a "symbol of humanity's power to shape a sustainable future". Blue whales are now making a recovery following decades of exploitation that nearly drove them out of existence.
7-12-17 Whales sneak into shallow water to eat salmon from hatcheries
Whales sneak into shallow water to eat salmon from hatcheries
Humpbacks have been spotted feeding on baby salmon bred for release into the wild to restock fisheries for the first time, competing with fishermen. No such thing as a free lunch? Not so for these whales. Humpback whales in south-east Alaska seem to have found their own chain of fast food restaurants: salmon hatcheries. While making a good meal for the whales, the habit may prove harmful to the local fishing industry. Hatcheries aren’t fish farms, but salmon nurseries. The idea is that the juvenile fish released into the ocean from the hatcheries increase the number of salmon available to catch without leading to overfishing of the wild stocks. Wild salmon spend the first part of their lives in streams where competition is fierce and many don’t make it. Hatcheries make sure enough salmon survive this crucial life stage, breeding them in captivity for six to 18 months before releasing them into the wild. Ellen Chenoweth at the University of Alaska Fairbanks first became interested in humpbacks feeding on juvenile salmon when she saw videos that hatchery staff had taken of whales swimming close to their hatchery’s release sites to feed. Normally whales feed at depth, out of sight, which makes their feeding habits difficult to study. They filter water through their baleen to catch krill and small fish – but seem to be equally at home around these new, human-made shallow hatcheries. “Whales are fascinating: mammals like us, but perfectly at home in an alien environment,” she says.
7-11-17 Whales feast when hatcheries release salmon
Whales feast when hatcheries release salmon
Crowded prey makes humpback whale feeding worth the effort — and helps explain a whale innovation: going out to dinner at fish hatcheries. Humpback whales, those innovative foodies, have discovered their own pop-up restaurants. Migrant humpbacks returning to southeastern Alaska in spring are the first of their kind known to make routine visits to fish hatcheries releasing young salmon into the sea, says marine ecologist Ellen Chenoweth. The whales are “40 feet long and they’re feeding on fish that are the size of my finger,” says Chenoweth, of the Juneau fisheries center of University of Alaska Fairbanks. For tiny prey to be worthwhile to humpbacks, it’s good to find crowds — such as young salmon streaming out of hatchery nets. Six years of systematic observations of whales at five hatcheries at Baranof Island reveal a pattern of humpbacks visiting during springtime releases, Chenoweth and her colleagues report June 12 in Royal Society Open Science. (Webmaster's comment: They've just learned where the food is.)
7-1-17 Vaquita porpoise: Dolphins deployed to save rare species
Vaquita porpoise: Dolphins deployed to save rare species
Mexico's government says it plans to use dolphins trained by the US Navy to try to save the world's most endangered marine species, the vaquita porpoise. Environment Minister Rafael Pacchiano said that the dolphins would be deployed to locate and herd vaquitas into a marine refuge. Mexico also permanently banned fishing nets blamed for the vaquitas' decline. Scientists estimate that fewer than 40 of the mammals are still alive in their habitat, in the Gulf of California. Mr Pacchiano said the dolphin project would begin in September. "We've spent the past year working alongside the US Navy with a group of dolphins they had trained to search for missing scuba divers," he told Formula radio. "We've been training them to locate the vaquitas. "We have to guarantee we capture the largest possible number of vaquitas to have an opportunity to save them." The Mexican government also said on Friday it was imposing a permanent ban on gillnets, used to catch totaba, which are highly valued in Chinese traditional medicine. The nets are designed to trap the heads of fish but not their bodies, but are blamed for trapping and killing the porpoises as well.
Dolphins communicate and see the world using echolocation with frequencies up to 150,000 hertz. We are limited to 22,000 hertz. We can not hear them talk, we can not image what they "see". They can "see" (echolocate) a tennis ball a football field away in murky water. A task hard for many of us even in clean air.
6-25-17 Whaling's 'uncomfortable' scientific legacy
Whaling's 'uncomfortable' scientific legacy
It's a curious thing to see a group of early whale foetuses up close - to see beings so small that have the potential to become so big. But what really strikes you, especially in those initial developmental stages, is how familiar the forms look. How like an early human foetus, they appear. "This is something you see time and time again in vertebrates, not just with mammals," says Richard Sabin, the Natural History Museum's top whale expert. "You see these similarities in the early developmental stages and it's really not until you're halfway through the gestation - which for a humpback whale is around 11 months - that you start to see the things that make that foetus characteristically the species that it is."
5-25-17 Giant octopus suffocates foolhardy dolphin that tried to eat it
Giant octopus suffocates foolhardy dolphin that tried to eat it
Dolphins have a special way of preparing the octopuses they eat – but when that goes awry the consequences can be deadly. A dolphin in Western Australia has bitten off more than it can chew. An attempt to eat a large octopus turned fatal when its airway was obstructed by a mass of tentacles. The Indo-Pacific bottlenose dolphin – known as “Gilligan” to researchers in the area – was found dead on Stratham Beach near the port city of Bunbury in August 2015. Octopus arms were seen hanging out of the side of its mouth. A post-mortem examination revealed one octopus tentacle extending down the dolphin’s oesophagus, and the other seven stuck in the back of its throat. The tentacle suckers were gripping the throat walls and had blocked off the airway, causing the dolphin to suffocate. The tentacles belonged to a Maori octopus (Macroctopus maorum), the largest species of octopus found in Australian waters and the third largest in the world. It is not unusual for bottlenose dolphins to feed on octopuses, but they normally break the body and tentacles into smaller pieces first using a “shake-and-toss” method. Shaking the octopus helps to kill it and tear it apart, while tossing prevents it from latching on and also weakens the suckers.
5-7-17 France bans captive breeding of dolphins and killer whales
France bans captive breeding of dolphins and killer whales
Pools for animals such as bottlenose dolphins must also be made significantly bigger under the rules. France has banned the breeding in captivity of dolphins and killer whales, in a move hailed by campaigners as a major victory. The government also banned the keeping of all whales, dolphins and porpoises in captivity, except for orcas and bottlenose dolphins already held. The association of French zoos complained they had not been consulted on the ban. But animal rights activists said it was a "historic French advance". The ban on captive breeding would eventually lead to the end of "marine circuses" in the country, a joint statement from five conservation groups including Sea Shepherd said. Environment Minister Segolene Royal had signed a version of the legislation on Wednesday, but decided to tighten the rules further and ban captive breeding completely after finding out that "some animals were drugged" in aquariums, the ministry told the AFP news agency. Jon Kershaw, who heads the Marineland Antibes park in the French Riviera, told local media that government's decision was a "bombshell". The new rules also ban direct contact between animals and the public, including swimming with dolphins, and require pools holding the animals to be made significantly larger. Establishments have six months to comply with some of the rules, and must expand their pools within three years. (Webmaster's comment: Zoos are an atrocity perpetuated on innocent and helpless animals because humans have the power to treat an animal anyway they want for the pleasure of humans. By What Right! Imprisoned creatures often become psychotic and go insane! Zoos are torture pure and simple. Who cares about how they make the animal feel. We don't seem to care. An animal wants to be free just as much as we do.)
4-26-17 Baby humpback whales 'whisper' to mums to avoid predators
Baby humpback whales 'whisper' to mums to avoid predators
The humpback whale is known for its loud haunting songs, which can be heard 20 miles away. However, new recordings show mothers and calves "whisper" to each other, seemingly to avoid attracting predators. The quiet grunts and squeaks can be heard only at close range. By calling softly to its mother, the calf is less likely be overheard and preyed on by killer whales, scientists believe. Dr Simone Videsen of Aarhus University in Denmark is part of a team of scientists who tracked eight baby whales and two mothers to learn more about the first months of a humpback whale's life. They used special sound and movement recorders, which were attached to the whale's skin via suction cups. "We were really surprised because humpback whales are really vocal normally and they have these long songs," she said. "But when you look at the communication pattern between mother and calf you see that they're often silent and they do produce these weaker signals."
4-25-17 How a dolphin eats an octopus without dying
How a dolphin eats an octopus without dying
Eating octopus can be dangerous. Some dolphins in Australia, though, have figured out how to do this safely — by shaking or tossing their prey over and over until it goes limp and the sucker-covered arms are relaxed and safe to eat. Most people who eat octopus prefer it immobile, cut into pieces and nicely grilled or otherwise cooked. For some, though, the wiggly, sucker-covered arms of a live octopus are a treat — even though those arms can stick to the throat and suffocate the diner if they haven’t been chopped into small enough pieces. Dolphins risk the same fate when eating octopus — and they can’t cook it or cut it up with a chef’s knife. “Octopus is a dangerous meal,” notes Kate Sprogis of Murdoch University in Australia. Even if a dolphin manages to remove an octopus’ head, it still has to deal with those sucker-covered tentacles. “The suckered arms would be difficult to handle considering dolphins don’t have hands to assist them,” Sprogis says. A group of hungry dolphins off the coast of Western Australia have figured out a solution. They shake and toss their prey until the head falls off, the animal is in pieces and its arms are tender and not wiggling anymore, Sprogis and her colleagues report April 2 in Marine Mammal Science.
4-11-17 Drone spots humpback whales and orcas moving in on cloud of fish
Drone spots humpback whales and orcas moving in on cloud of fish
Aerial photo shows mass of Atlantic herring that will soon be supper for humpback and killer whales in glowing water off the north Norway coast. Shallow waters glow in the midday sun off northern Norway, where a mass of Atlantic herring have caught the attention of humpback whales and killer whales. That large black splotch isn’t a sandbank: it’s a shoal of millions of fish about to be feasted upon. This photograph was shot using a drone last year off the island of Kvaløya. It was taken in January, a time of year when Norway sees little sunshine. Indeed, the light is coming from low on the horizon, despite it being midday. “It’s before we get the sun back,” says wildlife photographer Espen Bergersen. That’s what gives the water its vivid colour. Bergersen says it was -13°C on this day. “We were planning to go out in the boat, but it was freezing cold,” he says. “It was lucky I couldn’t start my boat, I guess. I decided to go up with my drone and got this photograph.” While operating the drone from a nearby bridge, he noticed whales circling its supports. “I haven’t seen them do that before,” he says. The herring populations have migrated northward over the past 10 to 15 years, Bergersen says, leaving behind the fjords of southern Norway and providing a new feeding ground for humpback whales. The whales stop by on their way from Svalbard – an archipelago between the North Pole and mainland Norway – to the Caribbean, where they spend the winter.
4-4-17 Dolphins 'shake and toss' octopus prey, research finds
Dolphins 'shake and toss' octopus prey, research finds
Octopuses can be a perfect meal for dolphins, but they can also pose a deadly choking hazard. So dolphins have developed elaborate behaviours to turn larger prey into more bite-size pieces, according to marine biologists in Australia. The researchers filmed dolphins shaking octopuses and tossing them through air in preparation for consumption. The findings, compiling years of observations, have been described in the journal Marine Mammal Science. "Everyone relates it to seafood preparation," lead author Dr Kate Sprogis told the BBC. "They've got skills to prepare their meal."
3-29-17 Inside knowledge: What’s really going on in the minds of animals
Inside knowledge: What’s really going on in the minds of animals
Bright animals from chimps to crows know what they know and what others are thinking. But when it comes to abstract knowledge, the picture is more mixed. WORKERS at the David Sheldrick Wildlife Trust in Nairobi, Kenya, claim that elephants know they will be looked after at its rescue centre, even if the animals have never been there. Elephants that have had no contact with the centre, but know others who have, often turn up with injuries that need attention. That suggests not only abstract knowledge, but relatively sophisticated communication of that knowledge. Either that, or wishful thinking on our part. The extent to which non-human animals “know” things is difficult to assess. The attribute known as “theory of mind” – the ability to know what others are aware of – has been demonstrated, although not always conclusively, in elephants, chimps, parrots, dolphins and ravens, for example. Dolphins are even aware of lacking knowledge. Train a dolphin to answer a question such as “was that a high or low-frequency tone you just heard?” and they give sensible answers, even giving a “don’t know” when the right response isn’t clear. Some primates spontaneously seek further information when posed a question that they can’t answer, suggesting they know both that they don’t know and that they can change that. Things look more mixed when we consider abstract knowledge: the ability we have to understand abstract properties such as weight or force, and squirrel away knowledge gained in one situation to be applied in some future, different context. Great apes instinctively know that, of two identical cups on a seesaw, the lower one is more likely to contain food. “They have a spontaneous preference, from the first time, for the lower cup,” says Christoph Voelter, who researches animal cognition at the University of St Andrews, UK. “They seem to have certain physical knowledge about the world.” New Caledonian crows, on the other hand, don’t have this know-how and make “mistakes” when assessing which stones will exert the most force on a lever to release food. “Crows aren’t using knowledge of force when initially solving the problem,” says Alex Taylor of the University of Auckland, New Zealand – rather, they seem to use trial and error.
3-10-17 Never-before-seen gatherings of hundreds of humpback whales
Never-before-seen gatherings of hundreds of humpback whales
The marine giants are gathering to feed in super-groups of 200, and no one knows why. It could be their natural behaviour when populations are at normal levels.In a mysterious change to their normal behaviour, humpback whales are forming massive groups of up to 200 animals. Humpbacks aren’t normally considered to be terribly social. They are mostly found alone, in pairs, or sometimes in small groups that disband quickly. But research crews have spotted strange new social behaviour on three separate cruises in 2011, 2014 and 2015, as well as a handful of public observations from aircraft. These super-groups of up to 200 were spotted feeding intensively off the south-western coast of South Africa, thousands of kilometres further north from their typical feeding grounds in the polar waters of the Antarctic. “It’s quite unusual to see them in such large groups,” says Gísli Vikingsson, head of whale research at the Marine and Freshwater Research Institute in Iceland.
2-9-17 Synchronised swimming seems to make dolphins more optimistic
Synchronised swimming seems to make dolphins more optimistic
Having a mate to swim with – and mirror their movements – appears to make zoo dolphins feel more positive about their prospects in life. Bottlenose dolphins that engage in synchronised swimming with their peers tend to see the glass as being half full. Some of these dolphins frequently swim in tight-knit groups, and they’re the ones who appear the most optimistic, according to a study of eight captive animals. In the experiment, individual dolphins were trained to swim towards one of two targets. They were taught that when they reach the left one, they receive applause and eye contact, while the one on the right delivers herring – the jackpot – and dolphins swim faster towards it. When presented with a new and ambiguous middle target, some dolphins still swim rather fast, presumably hoping they’ll receive another tasty herring, although it’s only a 50/50 chance. Those were dubbed the “optimistic” dolphins, and the analysis found that they were the same animals who had participated in the most synchronised swimming recently: moving closely alongside their fellow dolphins and matching their movements.
12-16-16 Mexico bid to save world's smallest vaquita porpoise
Mexico bid to save world's smallest vaquita porpoise
Mexican authorities and scientists are trying to save the world's smallest porpoise by capturing illegal "ghost" fishing nets. They have managed to remove more than 100 dumped or lost nets left floating in the sea from October to December. Local fishermen and conservationists helped to trawl 11,814km (7,340 miles) in the Gulf of California, the only area where the vaquita porpoise live. Its population is estimated to be down to about 60 individuals. Conservationists say they fear the porpoise will be extinct by 2022. The main threat to the porpoise are the nets used to illegally catch fish known as the totoaba which is hunted for its swim bladder - fetching tens of thousands of dollars on the black market in China.
11-28-16 Rare river dolphins get trapped in fishing nets as waters drop
Rare river dolphins get trapped in fishing nets as waters drop
Draining rivers for irrigation puts the Ganges river dolphin at higher risk of being ensnared by fishing nets. Nepal’s endangered river dolphins are in a tangle. Not only can they die in fishing nets, but farmers further threaten their survival by draining rivers for irrigation. A 15-year study of the Karnali river found that competing demands for river water, especially during the dry winter months, have led to a near halving of this river’s small population of blind Ganges river dolphins (Platanista gangetica gangetica). In 2010, severe flooding shifted the balance of water flow in a tributary of the Karnali river, from primarily flowing through a protected national park where fishing is restricted, to a region dominated by fishing and agriculture. Water levels in the national park reached below 2 metres – a minimum threshold required to sustain the dolphins. They responded by migrating to the now-deeper waters outside the park. The unusual event caught the attention of a research team in Nepal and India, led by conservation biologist Gopal Khanal at Nepal’s Tribhuvan University, who investigated how the change in habitat affected the dolphins.
11-21-16 Porpoises plan their dives and can set their heart rate to match
Porpoises plan their dives and can set their heart rate to match
The discovery suggests all cetaceans can do this, and provides a new clue to how noise pollution may trigger strandings. Two captive harbour porpoises called Freja and Sif have helped to reveal that porpoises —and probably all cetaceans — consciously adjust their heart rate to suit the length of a planned dive. By doing this, the animals optimise the rate at which they consume oxygen beforehand to match the intended depth and length of their dive. “Until now, we knew that the heart rates of porpoises and cetaceans in general correlate with different dive factors, such as dive duration, depth and exercise,” says Siri Elmegaard of Aarhus University in Denmark, who led the research. “Now we can conclude that harbour porpoises have cognitive control of their heart rate.”
11-3-16 City dolphins get a boost from better protection and cleaner waters
City dolphins get a boost from better protection and cleaner waters
Human activities such as manufacturing had made the Port River estuary near Adelaide, Australia, inhabitable to bottlenose dolphins. But the creation of a small sanctuary for the marine mammals and efforts to clean up the water appear to be helping, and the dolphins have returned. There are many places in the world where you can see bottlenose dolphins, but the dolphins swimming in the Port River estuary near Adelaide, Australia, are special. They gambol about in waters surrounded by factories, power stations and other signs of human habitation. For much of the 20th century, there were no dolphin sightings in the inner estuary. Prior to European settlement in 1858, bottlenose dolphins were commonly seen by the local Kaurna aboriginal tribal group. But as the city of Adelaide was built, the dolphins disappeared. What changed that enabled their return? A combination of improved environmental conditions, a little bit of protection and some public education, researchers report October 24 in Marine Mammal Science.
10-28-16 Last-ditch effort to save the world’s smallest porpoise agreed
Last-ditch effort to save the world’s smallest porpoise agreed
Critically endangered vaquitas are set for greater protection and Japan’s “scientific” whaling faces scrutiny thanks to international agreements. The vaquita, the world’s smallest porpoise, may be saved from extinction thanks to measures agreed yesterday at a meeting of the International Whaling Commission. Unique to the Gulf of California, this iconic animal has seen its numbers collapse from 567 individuals in 1997 to just 59 in 2015. The main reason is that they get accidentally caught and drowned in gill nets spread out to illegally catch totoaba fish, whose swim bladders are prized in Chinese medicine. Now, new measures will oblige the Mexican government to enforce gill-net bans throughout the range of the vaquita, also known as the “panda of the sea”. Likewise, efforts will be strengthened to eliminate the illegal trade in swim bladders from totoaba, and increase funding for vaquita monitoring programmes. “It’s not too late for the vaquita, but it’s going to be close, with only an estimated 59 animals left,” says Matt Collis, the team leader at the meeting for the International Fund for Animal Welfare. “What’s truly tragic is that this could have been entirely preventable, because we’ve long known where vaquitas live and what we need to do to protect them.”
10-11-16 Dolphin pictured killing porpoise by flipping it into air
Dolphin pictured killing porpoise by flipping it into air
A bottlenose dolphin has been pictured flipping a porpoise into the air in a deadly attack. The rarely seen event was witnessed by gig rowers in Newlyn Harbour in Cornwall. Dolphin attacks on porpoises accounted for about one death a year on average, said Cornwall Wildlife Trust (CWT). It is unclear why dolphins attack porpoises but it could be an aggressive response to feeding competition or even "misdirected sexual aggression".
9-30-16 Protect dolphins, UK government urged
Protect dolphins, UK government urged
Campaigners are demanding better safeguards for the UK's marine mammals after the EU said it would take Britain to court over harbour porpoises. The European Commission announced the action because it says the UK is failing to protect the endangered animals properly. The government is yet to comment on the court action. But the Wildlife Trusts are urging ministers to declare many more Marine Conservation Zones (MCZs). These would protect mammals round the shores. The Wildlife Trusts say safeguards to the UK's domestic marine life should be as strong as they are around Britain's overseas territories.
9-23-16 Dolphins have conversations
Dolphins have conversations
Dolphins have an elaborate spoken language and engage in conversations, Russian researchers have concluded. Marine biologists have recorded an exchange between Yasha and Yana, two Black Sea bottlenose dolphins that took turns producing a series of pulses, which the researchers identified as individual “words” strung together to form sentences. It’s well known that dolphins use pulses, clicks, and whistles to communicate, but the recordings reveal that they also alter the volume and pitch of the sounds they make, enabling them to convey messages and seemingly form sentences. The dolphins appeared to listen to each other without interrupting before responding—behavior reminiscent of a chat between well-mannered friends. While the researchers were unable to decipher what the dolphins were saying, their recordings suggest the marine mammals, which have larger brains than we do, communicate in a highly developed language. Researcher Vyacheslav Ryabov tells CNN.com that humans should create a device that could decode dolphin language and enable us to communicate. “We must take the first step to establish relationships with the first intelligent inhabitants of the planet,” Ryabov said.
9-21-16 How baby beluga whales dive deeper and longer than any others
How baby beluga whales dive deeper and longer than any others
Arctic sea ice forces baby belugas to hold their breath longer than other young whales. Special muscle adaptations help the babies survive. Their life amid the sea ice means the young whales do swim wild and free – from an early age, baby belugas must follow their mothers under the sea ice, where air holes are transient and scarce. Now we are learning how baby belugas achieve that: they are born with more mature diving muscles than any other marine mammals studied so far and they develop more rapidly over their first year of life. Shawn Noren at the University of California, Santa Cruz, and Robert Suydam from the Wildlife Management Department of Alaska’s North Slope Borough collected muscle samples from 23 female and male beluga whales of various ages and studied the biochemistry of their muscles. They found that belugas are born with much higher stores of myoglobin, an oxygen-binding protein, than other cetaceans (whales, dolphins and porpoises), making them better prepared for diving at birth than other species. Myoglobin allows oxygen to be stored and slowly released if an animal needs to hold its breath. The researchers showed that myoglobin in baby beluga whales increased by some 450 per cent between birth and their first birthday, to levels similar to those of fully grown adults. In fact, belugas have adult levels of myoglobin in their muscles by 14 months of age.
9-20-16 China’s fancy for ‘aquatic cocaine’ could wipe out rare porpoise
China’s fancy for ‘aquatic cocaine’ could wipe out rare porpoise
Illegal trade in the swim bladder of the totoaba fish fuels fishing practices that may drive the critically endangered vaquita to extinction. There are only around 60 vaquitas left, and it is now up to China whether the world’s smallest porpoise will escape extinction. That’s according to a report by campaign organisation the Environmental Investigation Agency (EIA). The critically endangered porpoise is only found in the Gulf of California, where it often gets tangled in gill nets targeting the totoaba, a similarly sized fish that is also endangered and whose fishing and international trade are banned. The totoaba’s swim bladders, known as “aquatic cocaine”, are sought for their putative medical effects, and can fetch tens of thousands of dollars in China. This trade still thrives there, despite a fall in prices and the ban, according to an investigation by the EIA.
9-8-16 White killer whales were legend – now they are everywhere
White killer whales were legend – now they are everywhere
White orcas are so rare, there was once only one. Now they are being spotted more frequently – and the reason is not good news. Six years ago, on 11th August 2010, whale researchers working in the western North Pacific encountered something very unusual: a white male killer whale, or orca. Two days later the white whale, nicknamed Iceberg, reappeared in a large group of orcas – a group that included a second white whale. In fact, over the past few years the researchers have encountered no fewer than five – and perhaps as many as eight – white orcas in the western North Pacific. They are virtually unheard of elsewhere in the world’s oceans. Their unusual abundance in this one particular region could be worrying evidence of inbreeding. “What we are seeing is strange. It’s a very high rate of occurrence,” says Erich Hoyt at Whale and Dolphin Conservation in Bridport, UK, who co-directs the Far East Russia Orca Project. Hoyt and his colleagues estimate there are several thousand orcas in the region, which could mean as many as one in 1000 individuals is born white. “All the other areas where orcas are studied intensively have zero or one or two [white whales] historically,” he says. Hoyt and his colleagues have not yet managed to take genetic samples from any of the white whales, so the exact reason for their unusual colour is not clear. One possibility, though, is that the whales are albinos – a condition that is often more common when mammal populations are inbred.
8-30-16 Endangered dolphin with broken blowhole learns to mouth-breathe
Endangered dolphin with broken blowhole learns to mouth-breathe
What to do when your blowhole is blocked? A dolphin has learned to breathe through its mouth instead, even though it’s not usually an option for them. A dolphin has learned to breathe through its mouth after developing a faulty blowhole, highlighting the animal’s ability to adapt. The adult Hector’s dolphin (Cephalorhynchus hectori) was discovered in January 2014 off the coast of Christchurch in New Zealand. Steve Dawson at the University of Otago in Dunedin, New Zealand, and his colleagues were studying the endangered species as part of a long-term conservation project, when they noticed unusual behaviour in one member of a group of seven. Each time the dolphin surfaced, it approached at a steep angle and lifted its head higher out of the water than normal. The blowhole stayed shut while its mouth opened wide and made a sound consistent with sucking in air. Dolphins were not thought to be able to breathe through their mouths. To do this, a dolphin would need to move its larynx from the usual position to allow the respiratory and digestive tracts to communicate, says Dawson.The animal probably learned to do this after its blowhole became blocked by a foreign object or injury, or because the muscles around it didn’t work properly, he says. “We think this dolphin has found a workaround to what is most likely a pathological problem.”
6-12-16 For harbor porpoises, the ocean is a 24-hour buffet
For harbor porpoises, the ocean is a 24-hour buffet
Harbor porpoises eat hundred of tiny fish every hour, capturing more than 90 percent of what they chase, a new study finds. Harbor porpoises are the world’s smallest cetaceans. The marine mammals, which look something like a small, beakless dolphin, live in colder waters of the Northern Hemisphere and tend to stick closer to shore — a trait that led to their name. Because small bodies would lose heat quickly in cold water, scientists have thought that harbor porpoises must eat a lot, consuming as much as 10 percent of their body weight daily, to stay warm and well fed. Now scientists have figured out just how good harbor porpoises are at finding a meal. These animals can go after hundreds of tiny fish each hour, and they are very successful hunters.
5-31-16 Orcas are first non-humans whose evolution is driven by culture
Orcas are first non-humans whose evolution is driven by culture
Genomes of 50 whales from different social niches reveal that their varying cultures are also genetically distinct. Many researchers accept that cultural experiences have helped shape human evolution – and evidence has now emerged that the same may be true of killer whales. Human genomes have evolved in response to our cultural behaviours: a classic example is the way that some human populations gained genes for lactose tolerance following the onset of dairy farming. But whether genomes and culture co-evolve in other animal species has been unclear. Andrew Foote at the University of Bern, Switzerland, and his colleagues suspected that killer whales might follow a similar pattern to humans.
4-15-16 Dolphins have a language that helps them solve problems together
Dolphins have a language that helps them solve problems together
When faced with a puzzle that two can solve better than one, bottlenose dolphins chatter away, suggesting that they have a specific vocalisation for working together. Bottlenose dolphins have been observed chattering while cooperating to solve a tricky puzzle – a feat that suggests they have a type of vocalisation dedicated to cooperating on problem solving. Holli Eskelinen of Dolphins Plus research institute in Florida and her colleagues at the University of Southern Mississippi presented a group of six captive dolphins with a locked canister filled with food. The canister could only be opened by simultaneously pulling on a rope at either end. The team conducted 24 canister trials, during which all six dolphins were present. Only two of the dolphins ever managed to crack the puzzle and get to the food.
3-10-16 Why killer wales should not be kept in captivity
Why killer wales should not be kept in captivity
For the last few years there has been a torrent of stories of captive orcas suffering severe health problems, and in some cases attacking and even killing their trainers. Many of these stories have focused on an orca called Tilikum, who lives at SeaWorld Orlando in Florida. Tilikum has been involved in three deaths during his time in captivity. SeaWorld has now announced that Tilikum's health appears to be deteriorating, possibly due to a bacterial infection in his lungs. In response, conservation groups are once again calling for an end to the practice of keeping orcas, and other large marine mammals, in captivity. Are they right?
2-29-16 Whale algorithm could unlock secrets of their many dialects
Whale algorithm could unlock secrets of their many dialects
Could we speak whale one day? A whale song algorithm can pick up their different dialects and could help work out how they communicate with one another. A computer has learned to suss out the different dialects of long-finned pilot whales. The approach is a step towards unlocking the secrets of how whales communicate with one another. Some marine mammals, like sperm whales, develop distinct songs that are particular to their social groups. Just as a human might pick up an accent or a set of idioms from their parents, so too whales have their own cultures of communication. Analysing whale song recordings can help us learn more about these differences. This process normally involves assessing recordings visually, with computers only used to check for specific features like whistles. But this means you might miss important clues to how the whales communicate, says Sarah Hallerberg at the Max Planck Institute for Dynamics and Self-Organization in Germany. “Some features that might seem very relevant to a human might be very different to the whale.”
1-23-16 The whales that speak in code to show their identity
The whales that speak in code to show their identity
Eavesdropping on sperm whales has revealed that they can convey a lot of information about themselves in just a few clicks. It has now become apparent that each individual whale makes unique calls. These are similar to two kinds of markers that humans use to identify ourselves: our names and voices. Each whale produces short bursts of clicks called "codas". They are so distinct, researchers can identify the whales from sound alone. (Webmaster's comment: And so can the whales identify each other. They have a language just like the dolphins do, and just like we do.)
1-22-16 Cross-species dolphin society gets friendlier after hurricanes
Cross-species dolphin society gets friendlier after hurricanes
Unusual coalitions of bottlenose and spotted dolphins drop their aggression following hurricanes, revealing peaceful interactions as the basis for mingling. The bottlenose and spotted dolphins of the Bahamas are unusual in that they often intermingle. Now, observations show these unusual coalitions survived two deadly hurricanes. Afterwards the dolphin interactions were less aggressive, perhaps to allow them to adjust to post-disaster life. Bottlenose and spotted dolphins in the Bahamas play and forage together, sometimes even babysitting each other’s young. But bottlenose males also routinely use their size advantage to forcibly hone their mating skills on their smaller cousin species.
12-3-15 Orcas seen in unique group ambush-and-kill attack on dolphins
Orcas seen in unique group ambush-and-kill attack on dolphins
A pod of killer whales known for invading beaches to catch baby sea lions has now been spotted using sophisticated ambush tactics to catch dolphins. They’ve definitely earned their name. Frighteningly effective hunting methods have become something of a speciality for a pod of killer whales off the coast of Patagonia, Argentina. The pod became famous when some of them were spotted intentionally beaching themselves to capture baby sea lions, then refloating when the next wave rolled in. Now the same pod has been seen tricking dolphins into an ambush. Orcas have been filmed hunting dolphins before, but never using such a complex group-hunting technique.
9-18-15 The inner lives of animals
The inner lives of animals
The evidence shows that elephants and apes mourn their dead, becoming listless and depressed. Dolphins can recognize their own reflections, have intricate social structures, and appear to call each other by individual names. Apes and chimps make tools, plan for the future, and display empathy and inferential reasoning. Primatologist Frans de Waal, writing in The New York Times about the recent discovery of a hominin ancestor with both human and ape characteristics, blames human vanity for the belief we are separate and distinct from the "extended family" of creatures on the great continuum of evolution. "The wall between human and animal cognition," de Waal says, "is like a Swiss cheese." If you doubt our kinship with the animal kingdom, I refer you to the daily news coverage of our species' Darwinian struggles for dominance and survival. Evolution is a work in progress: We are still closer to the beasts than to the gods.
7-22-15 Two dolphin species band together to form unprecedented alliance
Two dolphin species band together to form unprecedented alliance
Atlantic bottlenose and spotted dolphins are cooperating in unique mixed-species groups that are mostly platonic, but sometimes cross-species sex is involved. The dolphins of the Bahamas forage and play together and forge alliances – even though they belong to two distinct species. They’re not the only example of mixed-species dolphin groups, but this level of interaction is unprecedented.
4-4-15 Postmenopausal Orcas guide hunts
Postmenopausal Orcas guide hunts
By finding fish, older females improve survival of kin. Same as with elephants, the older females are the leaders. They are the custodians of Orca knowledge
3-30-15 Porpoises, whales and dolphins use 'sound searchlights'
Porpoises, whales and dolphins use 'sound searchlights'
Researchers in Denmark have revealed how porpoises finely adjust the beams of sound they use to hunt. The animals hunt with clicks and buzzes - detecting the echoes from their prey. This study showed them switching from a narrow to a wide beam of sound - "like adjusting a flashlight" - as they homed in on a fish.
9-9-14 Are dolphins cleverer than dogs?
Are dolphins cleverer than dogs?
For decades now, dolphins and dogs have vied for the title of most intelligent animal. But which is actually cleverer, and can the two even be compared?
3-26-14 Dolphin whistle instantly translated by computer
Dolphin whistle instantly translated by computer
Software has performed the first real-time translation of a dolphin whistle - and better data tools are giving fresh insights into primate communication too
8-6-13 Dolphins have 'longest social memory' among non-humans
Dolphins have 'longest social memory' among non-humans
Forget about elephants - scientists say that dolphins have the longest memories yet found in a non-human species.
7-22-13 Dolphins 'call each other by name'
Dolphins 'call each other by name'
Scientists have found further evidence that dolphins call each other by "name".
1-28-13 Dolphins try to save dying companion
Dolphins try to save dying companion
Common dolphins have been seen gathering to aid a dying companion, trying to support it in the water and help it breathe.
10-22-12 Dolphin 'sponging' spans centuries
Dolphin 'sponging' spans centuries
Bottlenose dolphins using sponges to protect their noses while foraging is a technique that the animals discovered in the 19th century, a study has found.
3-28-12 Bottlenose dolphins: 'Gangs' run society, scientists say
Bottlenose dolphins: 'Gangs' run society, scientists say
Male bottlenose dolphins organize gang-like alliances - guarding females against other groups and occasionally "changing sides".
2-21-12 Dolphins deserve same rights as humans, say scientists
Dolphins deserve same rights as humans, say scientists
Dolphins should be treated as non-human "persons", with their rights to life and liberty respected, scientists meeting in Canada have been told.
12-7-07 Animals Do the Cleverest Things
Animals Do the Cleverest Things
The chimp who outwits humans; the dolphin who says it with seaweed; the existential dog -- the more we learn about other animals the harder it is to say we're the smartest species.
10-31-06 Elephants' jumbo mirror ability
Elephants' jumbo mirror ability
Elephants can recognize their own reflection, showing self-awareness seen before only in humans, great apes and bottlenose dolphins, scientists say.