Cuvier’s beaked whales, world’s deepest diving mammals


This June 2017 video says about itself:

Sea Shepherd Captures NEVER SEEN BEFORE drone footage of the rare Cuvier’s Beaked Whales (Ziphius cavirostris) while conducting research on Mexico’s Guadalupe Island.

From Duke University in the USA:

Beaked whales‘ incredible diving abilities confirmed

Cuvier’s beaked whales go a mile deep, hold breath for an hour

February 6, 2019

A new Duke University-led study provides the first detailed record of the diving behavior of Cuvier’s beaked whales in U.S. Atlantic waters.

Cuvier’s beaked whales are the world’s deepest-diving mammal, but studies of their behavior are constrained by the animals’ offshore location and limited time spent at the surface.

The new data, recorded from 5,926 dives of tagged whales off Cape Hatteras, N.C., showcases the remarkable diving abilities of these animals and provides new clues to how they make a living at the extremes of depth and cold.

“Their deep dives average about 1,400 meters, lasting about an hour, while they are feeding near the sea floor. They typically only spend about two minutes at the surface between dives,” said Jeanne Shearer, a doctoral student in ecology at Duke University’s Nicholas School of the Environment. “It’s amazing that they can dive to such depths, withstand the pressure, and be down there that long, with such brief recovery times.”

Past studies have documented the diving behavior of Cuvier’s beaked whales in Pacific waters, Italy, and the Bahamas, but this is the first one focused in the U.S. Atlantic. Scientists estimate about 6,500 Cuvier’s beaked whales live in the northwest Atlantic. Populations in different areas exhibit some differences in diving behavior, highlighting the need for data from around the world.

To conduct the study, scientists attached LIMPET satellite-linked tags to 11 Cuvier’s beaked whales that live and dive most of the year in waters a two-hour boat ride from Cape Hatteras. One tag failed, but the other 10 recorded 3,242 hours of behavioral data from 5,926 individual dives — both deep and shallow — between 2014 and 2016.

Aside from the extremely deep dives that these whales are able to make, the data showed that they dive nearly continually, with deep dives followed by 3-4 shallow dives that extend to around 300 meters. How they continuously dive to these depths without long recovery periods is still a mystery to scientists.

“Cuvier’s beaked whales are only half the size of the sperm whale,” Shearer said. “Their dives push the limits of mammalian physiology, but we still don’t know how they’re able to behave this way.”

She and her colleagues published their peer-reviewed findings Feb. 6 in the journal Royal Society Open Science.

Aside from adding to our knowledge of the species’ remarkable diving capability, the findings provide a baseline for controlled experiments, now underway at Duke, to study their reactions to low levels of sonar.

“It’s important to understand their typical diving behavior in order to interpret the results of behavioral response studies,” said Shearer, who conducts her research at the Duke University Marine Laboratory in Beaufort, N.C.

“These animals are fascinating and there is so much we still don’t know about their behavior and physiology,” Shearer said. “They are the world’s deepest mammalian divers, but we don’t yet understand how they dive to such extremes.”

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Beaked whales’ feeding disturbed by navy sonar


This June 2017 video says about itself:

Sea Shepherd Captures NEVER SEEN BEFORE drone footage of the rare Cuvier’s Beaked Whales (Ziphius cavirostris) while conducting research on Mexico’s Guadalupe Island.

This is the first ever footage of a mother and calf pair of this species.

From the Monterey Bay Aquarium Research Institute in the USA:

Why do beaked whales return to a Navy sonar range despite frequent disturbance?

Scientists say it’s the food

January 29, 2019

Using data from underwater robots, scientists have discovered that beaked whales prefer to feed within parts of a Navy sonar test range off Southern California that have dense patches of deep-sea squid. A new study published in the Journal of Applied Ecology shows that beaked whales need these prey hotspots to survive, and that similar patches do not exist in nearby “sonar-free” areas.

For decades, the U.S. Navy has used high-powered sonar during anti-submarine training and testing exercises in various ocean habitats, including the San Nicolas Basin off Southern California. Beaked whales are particularly sensitive to these kinds of military sonars, which sometimes result in mass stranding events. Following legal action from environmental activists related to these risks, the Navy modified some training activities, created “sonar-free” areas, and spent more than a decade and tens of millions of dollars trying to find ways to reduce the harm to beaked whales and other mammals.

The new research, led by Brandon Southall at the University of California, Santa Cruz, and Kelly Benoit-Bird at the Monterey Bay Aquarium Research Institute, aimed to better understand why whales keep returning to the test range despite the risks.

The researchers equipped an underwater robot with echosounders to measure the abundance, density, and sizes of deep-sea squids in different parts of the Navy test range, as well as in nearby waters. They also developed an “energy budget” for beaked whales, showcasing the costs — in time and calories — of hunting for squid. This helped the researchers estimate how many dives the whales needed to make in order to get enough food to survive in different areas.

“Beaked whales work very hard to obtain their food. They are essentially living paycheck to paycheck”, said Benoit-Bird. Unlike many baleen whales with significant energy reserves, beaked whales can’t afford to expend too much energy on a dive that doesn’t result in capturing many squid. In areas where the concentration of prey is low, the beaked whales must work harder and expend more calories — making reproduction and raising young that much more challenging. Some of the areas under study were so poor in terms of prey that whales likely could not meet their basic energetic requirements if they only fed there.

“Despite how things might look from the surface, the deep sea is not uniform,” Benoit-Bird added. “There are pockets of wealth where squid are abundant, and beaked whales know exactly how to find those hot spots.” It turns out that a portion of the Navy test range off Southern California encompasses one of these hot spots — an area rich in squid.

In fact, squid were 10 times more abundant higher in the area preferred by the whales. In this preferred area, the whales could get enough food by making just one dive a day. In a nearby sonar-free area (established with the idea that beaked whales could shelter in these areas while the sonar tests were underway) the whales would need to make between 22 and 100 dives per day to get enough food — something that would be difficult or impossible to do.

“Our findings, based on a novel integration of active sonar imaging and passive listening technologies, have multiple management implications”, explained Southall. “They provide direct information to the Navy and federal regulators to better manage important and impacted habitat areas off California. And they give us new data on foraging ecology for population-level models of disturbance that have been at the heart of recent debate and litigation over spatial management and proposed sonar exclusion zones.”

This study is the first to link habitat quality with beaked whale behavior in such fine spatial scales. It also demonstrates that scientists can’t assess the quality of deep-sea habitats by simply making measurements at the ocean surface, or even by measuring the physical and chemical properties of the deep ocean. Direct measurements of the prey environment at the depths where animals are feeding, coupled with observations of when and where animals are foraging, are critical.

Until now, collecting such detailed data, even over small time and space scales, was virtually impossible. The researchers are now working on tools that will help them study predators and prey over longer time periods, and in other areas where the Navy operates high-powered sonar. Similar field-research and modeling techniques could also be used to assess the potential impacts of other human activities that may disturb ocean animals, such as shipping traffic or offshore oil and gas development.

Ancient baleen whale evolution, new research


This March 2014 video says about itself:

A prehistoric whale graveyard was discovered in a Chilean desert a few years ago, and no one could figure out how the whales all died together half a mile from the coast… until now. Anthony is here to tell you how something as small as algae might have killed dozens of whales at once.

From the University of Otago in New Zealand:

Piece to the puzzle of baleen whales’ evolution

January 22, 2019

An Otago researcher has added another piece to the puzzle of the evolution of modern baleen whales with a world-first study examining the teeth and enamel of baleen whales’ ancestors.

Modern baleen whales have no teeth when adults, instead they use large keratin plates called baleen to filter prey from large volumes of seawater. However, millions of years ago their ancestors had teeth as most mammals do.

Lead author of the research just published in the Journal of Mammalian Evolution, Dr Carolina Loch from the Faculty of Dentistry, explains scientists are still trying to understand how and why this process happened. The research she carried out together with colleagues from the National Scientific and Technical Research Council in Argentina, CONICET, and the Swedish Museum of Natural History has provided more information.

They studied details of the inside structure of the teeth of two fossil whales from around 35 million years ago. These teeth were collected in Antarctica by the Argentinian and Swedish study co-authors Monica Buono and Thomas Mörs. Because teeth are naturally heavily mineralised, they preserve well in the fossil record and can provide clues of how extinct animals lived.

“We looked at how the enamel — the hard outside cover of teeth — and dentine, the core ‘living’ part, were structured and how similar or different they were from teeth of living whales, other fossil whales and other mammals,” Dr Loch explains.

“Both fossil whales we analysed (basilosaurid and fossil mysticete) had a complex enamel layer with biomechanical structures that suggest they were capable of heavy shearing and processing of their prey”, she says.

The enamel layer of the fossil mysticete they studied was the thickest enamel layer ever observed among cetaceans, both extinct and living.

“This is quite puzzling; baleen whales’ ancestors had teeth with complex and thick enamel, but millions of years later the teeth were ‘lost’ and replaced with large keratin plates called baleen”, Dr Loch says.

Because of the rarity of the material examined, Dr Loch says it is quite significant that the researchers were able to study them.

“Scanning electron microscopy is considered a ‘destructive’ type of analysis because the specimens need to be cut, polished and gold coated. It is fantastic that some museum curators are open to facilitate this kind of research and allow us to unravel new and important information.”

The study of the structure of the enamel and dentine of animals, both fossil and living, is a strength of Dr Loch’s research programme. Last year, the University of Otago highlighted another of her projects examining bottlenose dolphin teeth to help understand coastal contamination.

She hopes to continue studying teeth to help learn about how past animals lived and interacted with the environment, showing the breadth of the multidisciplinary research carried out in the University’s Faculty of Dentistry.

“As more fossil whales and other mammals are discovered and described, there is more material to be studied. I will continue working in partnership with colleagues overseas and in New Zealand in order to add small pieces to this puzzle — one tooth at a time.”

Japanese whalers kill whales for dog food


This 2017 video says about itself:

Illegal Japanese whaling filmed by the Australian Government in Antarctica

This is the footage that the Australian Government didn’t want you to see. Since 2012, Sea Shepherd has been a part of a joint fight to get the Australian Government to release rare whaling footage obtained on a 2008 Australian Customs mission to the Antarctic.

Here is the footage that the Australian Government filmed with tax payers’ money, of the Japanese whaling fleet illegally whaling in Antarctica, in Australian waters. The footage was filmed as part of gathering evidence for the International Court of Justice, which found Japan’s whaling to be illegal.

By Peter Frost in Britain:

Friday, January 11, 2019

Japan is still killing whales that they don’t even eat

This summer the Japanese will start killing whales again. PETER FROST wonders why

ON Boxing Day 2018 Japan announced that it is leaving the International Whaling Commission to resume commercial, rather than so-called scientific hunts for the animals for the first time in 30 years.

At the same time it said it would no longer go to the Antarctic for its much-criticised annual killings.

Chief Japanese Cabinet Secretary Yoshihide Suga said his country would resume commercial whaling in July 2019 “in line with Japan’s basic policy of promoting sustainable use of aquatic living resources based on scientific evidence.”

He added that Japan is disappointed that the IWC — which he claims is dominated by conservationists — focuses on the protection of whale stocks even though the commission has a mandate for both whale conservation and the development of the whaling industry.

“Regrettably, we have reached a decision that it is impossible in the IWC to seek the coexistence of states with different views,” he said at a news conference.

Japan faced much criticism earlier last year when its so-called scientific research whaling fleet slaughtered 122 pregnant whales.

In 2014, the international court of justice ruled against the annual Japanese slaughter of whales in the Southern Ocean, after concluding that the hunts were not, as Japanese officials had claimed, conducted for scientific research but for the commercial whale meat market.

Japan resumed whaling in the Southern Ocean in 2016 under a programme that reduced its kill by about two-thirds.

Australia and New Zealand, as well as several anti-whaling campaigning groups, have done what they can to stop the Japanese whaling in the Southern Ocean and they seem to have been successful – the Japanese now say that whaling this summer will only be in Japanese waters.

However the Japanese whaling fleet will again flaunt international opinion and start hunting whales later this year.

Japan will also continue to campaign to end the international ban on commercial whaling, claiming that populations of some whale species have recovered sufficiently to allow the resumption of what Japan claims is sustainable hunting.

Japan sent no fewer than 70 delegates to last autumn’s IWC meeting in Brazil. They argued that the 1986 moratorium on commercial whaling was intended to be a temporary measure, and accused the IWC of abandoning its original purpose — managing the sustainable use of global whale stocks.

The Japanese said: “Japan proposes to establish a committee dedicated to sustainable whaling (including commercial whaling and aboriginal subsistence whaling).”

The Japanese proposals would have allowed IWC’s members to decide on quotas with a simple majority rather than the current two-thirds majority from 2020 onwards. This would have made it easier for Japan to buy enough votes to end the ban on commercial whaling.

Votes in favour of whaling come from those nations still involved in the grisly business. Only Norway and Iceland still have commercial whaling fleets and they both support Japan.

In addition a number of small island communities also carry out limited aboriginal whale hunting as part of what are usually claimed to be ancient cultural traditions.

Japan, however, has often bought additional votes supporting whaling from countries by offering advantageous trading terms and other close relationships.

Does Japan need to eat whale meat? No. In fact very little whale meat is actually consumed by Japanese people today.

Much is made into expensive edible dog treats for the small lap-dogs that are so fashionable among affluent Japanese.

When it comes to human consumption a recent poll commissioned by Greenpeace and conducted by the independent Nippon Research Centre found that 95 per cent of Japanese people very rarely or never eat whale meat.

Given how Japan has leant over backwards to justify its whaling, and how much international criticism its getting, you might conclude whale meat is a hugely important part of the Japanese diet.

In fact the amount of uneaten frozen whale meat stockpiled in Japan doubled to 4,600 tons in the 10 years between 2002 and 2012, the last dates for which figures have been published.

It isn’t as if there is a long Japanese tradition of eating whale meat going back centuries. In fact the widespread eating of whale was only introduced directly after World War II by the US General Douglas MacArthur, who effectively ruled Japan during the post-war allied occupation.

World War II shattered Japan’s economy, food was scarce and meat especially so. MacArthur and his occupying administrators decided Japan could and should get much of their protein from sea mammal meat.

In 1946, MacArthur converted two US military tankers to become giant industrial whaling factory ships. A generation of Japanese children grew up eating whale meat as part of their school dinners.

Today for most Japanese, whale meat is little more than a novel culinary curiosity. For those few Japanese old enough to remember eating whale in immediate post-war school dinners it provides an occasional nostalgic trip down memory lane.

Japan’s former top international whaling negotiator Komatsu Masayuki for instance, told the world’s press he had never tried whale meat before he took on the whaling propagandist’s job.

This was the top man putting Japan’s argument for continuing to kill and eat whales saying he had never even tasted whale meat.

Why is it then that Japan is prepared to make itself such a pariah in world opinion? One popular view, and it is certainly the one I subscribe to, is that it is Japanese pride that will not accept other countries defining just what the Japanese nation can and cannot do.

Pride and humiliation are two sides of the way that Japanese people see their position in society and their nation’s place in the world.

If the world in general thinks it can tell the Japanese to stop killing whales, then that might be all the argument the Japanese need to keep up the bloody slaughter.

Some better whale news

Back in last September I wrote about a beluga whale that was spotted in the River Thames.

According to experts the 11-foot (3.5m) whale is still alive and well, and has been spotted regularly almost every week off the Kent coast in the Thames estuary.

Fin whales resident in Gulf of California


This 18 July 2018 video is called RARE FOOTAGE OF FIN WHALE GROUP BEHAVIOUR.

From Oregon State University in the USA:

Far-ranging fin whales find year-round residence in Gulf of California

January 10, 2019

Researchers from Mexico and the United States have concluded that a population of fin whales in the rich Gulf of California ecosystem may live there year-round — an unusual circumstance for a whale species known to migrate across ocean basins.

What makes the discovery even more unusual, researchers note, is that they identified the pattern of movement of the fin whales, which are the second largest whale species in the world, using a satellite tracking data set from 2001. Oregon State University professor Bruce Mate, director of OSU’s Marine Mammal Institute and co-author on the study, tagged 11 whales that year and was able to record the movements of nine of them for up to a year.

Since then, the OSU scientists have worked with colleagues in Mexico to further study the whales, in the process identifying via a 2011 photograph at least one female fin whale from the 2001 study — this time, with a calf, indicating the whales may even stay in the region for breeding and calving.

Results of the study are being published today in the journal PLOS ONE.

“One reason we decided to go back to this data set is that we know very little about fin whales in this region”, said Daniel Palacios, who holds the Endowed Faculty in Whale Habitats position at Oregon State’s Marine Mammal Institute, and is co-author on the study. “It is fairly remote, it is not densely populated and it requires expensive technology to track whales over time.”

“Researchers have known since at least the mid-1980s that fin whales inhabited the Gulf of California, but we just haven’t been able to get much information about them. As it turns out, we had an important piece of the puzzle in the tracking data set we just hadn’t yet fully analyzed.”

The researchers were able to reach several conclusions, based on extensive analysis of the tracking record of the 2001 satellite telemetry data coupled with more recent observations of the region’s weather patterns, acoustic data, and studies of potential food for the fin whales, in particular, krill and small fish.

  • There may be as few as 100 or as many as 700 “resident” fin whales in the Gulf of California, with the best guess at around 600. Other migrating fin whales also may visit the region seasonally and intermix with the resident population;
  • The researchers believe the Gulf of California is a microcosm for what fin whales face in the larger ocean environment, where they may migrate for thousands of miles in search of the most productive food resources — and possibly breeding and calving grounds.
  • The fin whales in the Gulf of California may have everything they need in one location, though they are more likely to spend the warmer months in one part of the gulf and the cooler months in another — likely in response to changes in prey abundance.

“The Gulf of California has a strong seasonal transition driven by changing atmospheric winds that produce upwelling and productivity,” said OSU’s Palacios, who specializes in the habitats of whale species. “Over the course of the seasons, different parts of the gulf light up and there are hot spots of productivity. Whales have learned to identify these areas and have adapted their movements to track this seasonal shift.”

Fin whales are the second largest whale species in the world after blue whales. They are thought to reach as much as 80 feet in length and weigh up to 100 tons. Heavily hunted during the whaling era, their populations have slowly but steadily rebounded because of international protection and the fact that they consume fish as well as krill and other crustaceans.

As a reflection of this, the global conservation status of fin whales was recently upgraded from “endangered” to “vulnerable” by the International Union Conservation of Nature (IUCN) Red List.

Palacios said he hopes the Oregon State researchers and their colleagues from Mexico can return to the region and utilize newly developed tags that will be able to not only collect location data, but record how often the whales dive, how deep, and whether they are eating.

“Feeding year-round is what separates fin whales, blue whales and related species from other baleen whales,” Palacios said. “We think they are finding enough food in the gulf to stay there year-round, but we’d like to document that over a period of years.”

The study is important because marine mammals in the Gulf of California are threatened by illegal fishing and boating activity. One fish in particular — the totoaba — is illegally harvested by fishermen who sell the swim bladder in Asian markets as a supposed aphrodisiac.

In addition to threatening the fish population, the activity has had significant impact on the world’s smallest and most endangered marine mammal — the vaquita. A member of the porpoise family, its dwindling numbers are partially a result of bycatch from that illegal fishing. Some researchers estimate that only 30 vaquita remain alive in the gulf.

Finally, the ship traffic from illegal [activity] in the gulf — including illegal fishing and drug running — may lead to increased risk of collisions with whales, which could threaten this population of fin whales, Palacios said.

“There is only one other place in the world that appears to have a resident population of fin whales, and that’s in the Mediterranean,” he said. “We’d like to find out more about how this unusual population has carved out its niche and what may define — and threaten — its success.”

The OSU Marine Mammal Institute is headquartered at the university’s Hatfield Marine Science Center in Newport, Oregon.

Ancient whale Basilosaurus, new research


This is a BBC Basilosaurus video.

From PLOS:

15-meter-long ancient whale Basilosaurus isis was top marine predator

Fossils from ‘Valley of Whales’ suggest B. isis predated smaller whales and fish

January 9, 2019

The stomach contents of ancient whale Basilosaurus isis suggest it was an apex predator, according to a study published January 9, 2019 in the open-access journal PLOS ONE by Manja Voss from the Museum für Naturkunde Berlin, Germany, and colleagues.

The authors uncovered an adult B. isis specimen in 2010 in the Wadi Al Hitan (“Valley of Whales”) site in Cairo, Egypt. This site was once a shallow sea during the late Eocene period and is remarkable for its wealth of marine fossils. While excavating this main B. isis specimen, the authors also revealed the remains of sharks, large bony fish, and, most numerously, bones from Dorudon atrox, a smaller species of ancient whale. The Basilosaurus skeleton was distinct from other skeletons in the cluster, containing pointed B. isis incisors and sharp cheek teeth as well as bones. Most of the fish, and Dorudon whale remains showed signs of breakage and bite marks, were fragmented, and tended to be clustered within the body cavity of the B. isis specimen.

One hypothesis to explain the clustering of these remains was that D. atrox had scavenged the B. isis carcass and fish. However, the D. atrox were juveniles, capable only of drinking mother’s milk. Bite marks on prey skulls also indicated predation rather than scavenging, since predators commonly target the head. The authors therefore position B. isis as a top predator which ate its prey live, rather than by scavenging. They propose that the remains of fish and juvenile D. atrox in the cluster are remnants of previous B. isis meals, while the teeth of sharks indicate postmortem scavenging.

Voss and colleagues draw a comparison with the modern-day killer whale (Orcinus orca), another toothed whale apex predator which often feeds on smaller whales and frequently hunts humpback whale calves during humpback calving season. The authors hypothesize that the Wadi Al Hitan site was a whale calving site for prey whale Dorudon, making it a hunting site for top predator B. isis during the late Eocene.