Russian gray whale Varvara, longest mammal migration


This video from the USa is called Gray Whale Migration.

From Treehugger.com:

Longest mammal migration ever recorded measures in at 14,000 miles

Melissa Breyer

April 16, 2015

And the remarkable journey is raising questions about the status of a critically endangered whale species.

In a study using satellite-monitored tags to track three western gray whales, a team of U.S. and Russian researchers recorded a stunning round-trip trek of 14,000 miles. The trio traveled from their primary feeding ground off of Sakhalin Island in Russia across the Pacific Ocean and down the west coast of California to Baja, Mexico and back home again.

One of the whales, dubbed Varvara by the scientists, visited the three major breeding areas for eastern gray whales, which are found off North America.

For a long time it was believed that western gray whales had gone extinct, but a small group was discovered in Russia off Sakhalin Island; they now number around 150 individuals and have been monitored by scientists from Russia and the U.S. since the 1990s. Meanwhile, populations of eastern gray whales were also in a tight spot, but conservation efforts have brought them back – today they are believed to have a population of some 18,000.

But here’s why Varvara’s visit to the eastern gray whales is interesting. Not all experts believe that the two species are in fact distinct, separate species. A number of scientists have proposed that western and eastern gray whale populations are not isolated and that the gray whales found in Russian waters are a part of an eastern population that is restoring its former range.

“The fact that endangered western gray whales have such a long range and interact with eastern gray whales was a surprise and leaves a lot of questions up in the air,” said Bruce Mate, director of the Marine Mammal Institute at Oregon State University and lead author on the study. “Past studies have indicated genetic differentiation between the species, but this suggests we may need to take a closer look.”

“The ability of the whales to navigate across open water over tremendously long distances is impressive and suggests that some western gray whales might actually be eastern grays,” Mate said. “But that doesn’t mean that there may not be some true western gray whales remaining.

He adds, “If so, then the number of true western gray whales is even smaller than we previously thought.”

Does this spell doom for the western whales? Protecting them has proven challenging. Five western grays have perished in Japanese fishing nets within the last 10 years and their feeding grounds off Japan and Russia include fishing areas, shipping corridors, and oil and gas production – as well as future sites oil sites. But with this new research, hopefully fresh data and visibility will inspire some momentum in conservation efforts. With so few of these wandering giants left, and maybe even fewer than we thought, the time is now.

Deep sea sperm whale, video


This video says about itself:

Rare Sperm Whale Encounter with ROV | Nautilus Live

14 apr. 2015

At 598 meters (1,962 ft) below the Gulf of Mexico off the coast of Louisiana, ROV Hercules encountered a magnificent sperm whale. The whale circled Hercules several times and gave our cameras the chance to capture some incredible footage of this beautiful creature. Encounters between sperm whales and ROVs are incredibly rare.

E/V Nautilus is exploring the ocean studying biology, geology, archeology, and more. Watch http://www.nautiluslive.org for LIVE video from the ocean floor. For live dive updates follow along on social media at http://www.facebook.com/nautiluslive and http://www.twitter.com/EVNautilus on Twitter.

Baleen whale evolution, new research in New Zealand


This video is called Humpback whales feeding on krill – Deep into the Wild – BBC. It says about itselF:

26 July 2010

Nick Baker crosses some of the world’s most treacherous seas as his mission to get close to some of the wildest animals on Earth takes him to Antarctica. Despite the cold, these oceans are rich with marine life as the mighty humpback whale demonstrates as it gorges itself on krill.

From the University of Otago in New Zealand:

Otago research details 40 million-year-old family tree

Wednesday, 15 April 2015, 3:11 pm

Otago research details 40 million-year-old family tree of baleen whales

New University of Otago research is providing the most comprehensive picture of the evolutionary history of baleen whales, which are not only the largest animals ever to live on earth, but also among the most unusual.

Most other mammals feed on plants or grab a single prey animal at a time, but baleen whales are famous for their gigantic mouths and their ability to gulp and filter an enormous volume of water and food.

In a paper appearing in the UK journal Royal Society Open Science, Otago Geology PhD graduate Dr Felix Marx and Professor Ewan Fordyce present a comprehensive family tree of living and extinct baleen whales stretching back nearly 40 million years.

The pair says that similar family trees have been constructed before, but theirs is by far the largest and, crucially, the first to be directly calibrated using many dated fossils.

The research shows which whales are related and exactly how long ago every branch of the tree—whether extinct or still alive—first arose.

This new family tree allows the researchers to estimate: (1) how many species of baleen whale have existed, (2) similarities and differences between different lineages in terms of overall body shape, and (3) how fast baleen whales evolved at any chosen time over the last 40 million years.

“We find that the earliest baleen whales underwent an adaptive radiation, or sudden ‘evolutionary burst’, similar to that of ‘Darwin’s finches’ on the Galapagos Islands,” says Professor Fordyce.

Dr Marx adds that this early phase of whale evolution coincided with a period of global cooling. At the same time, the Southern Ocean opened, and gave rise to a strong, circum-Antarctic current that today provides many of the nutrients sustaining the modern global ocean.

The researchers found that during their early history, whales branched out into many different lineages, each with a unique body shape and feeding strategy.

“Rather surprisingly, many of these early whales were quite unlike their modern descendants: Although some had baleen, others had well-developed teeth and actively hunted for much bigger prey than is taken by modern species,” says Professor Fordyce.

Yet, after a few million years of co-existence, the toothed ‘baleen’ whales disappeared, leaving behind only their filter-feeding cousins, he says.

That extinction occurred between 30 and 23 million years ago and was about the time that the circum-Antarctic current reached its full strength, providing more nutrients that made filter feeding a more viable option.

The researchers say that the toothed ‘baleen’ whales disappeared perhaps because of increasing competition from other newly evolved toothed marine mammals, such as dolphins and seals.

They found that filter-feeding whales remained successful and diverse until about 3 million years ago, when the number of lineages suddenly crashed.

“This decline was driven mainly by the disappearance of small species of baleen whale, which left behind only the giants—ranging from 6 to as much as 30 metres—that plough the ocean today,” says Dr Marx.

He says the disappearance of small whales likely resulted from the onset of the ice ages, which altered the distribution of available food, caused shallow water habitats to shift or sometimes disappear, and created a need for long-distance migration between polar feeding grounds and equatorial breeding grounds.

“This behaviour—long distance-migration—is still one of the hallmarks of all baleen whales alive today,” notes Professor Fordyce.

See also here. And here.

Fossil whale discovery in Vietnam


Whale fossil, discovered in Vietnam

From Vietnamnet:

06/04/2015

Local resident discovers whale fossil in Ha Tinh

A large piece of a whale‘s fossilised vertebra has just been found in the central province of Ha Tinh.

The fossil, measuring 37cm by 35cm by 80cm and weighing 19kg, was discovered accidentally at Thach Khe metal mine, 1km from Thach Hai Beach, by a local person named Duong Dinh Canh.

Director of Ha Tinh Museum Nguyen Tri Son and Australian archaeologist Philip Palmer examined the fossil and determined it was part of a whale‘s vertebral column. But they cannot determine the exact age of the fossil till some more research is done.

The experts will soon transport the fossil to the provincial museum for further study and exhibition.

Gray whale spring migration


This video from the USA is called Gray Whale Migration.

From the Everett Herald in Washington sate, USA:

Saturday, April 4, 2015, 12:01 a.m.

Gray whales make their annual return, though a bit late

By Sharon Salyer

Gray whales have been spotted near Whidbey and Camano islands, part of their annual spring layover on their way from Mexico to Alaska. You don’t necessarily have to board a boat to see their heart-shaped spouts and their V-shaped flukes. They can be spotted from shoreline areas in Snohomish County and from spots such as Cama Beach State Park on Camano Island and Ebey’s Landing beach and bluffs on Whidbey Island, according to the Orca Network.

The whales’ return was just a tad off schedule this year, said John Calambokidis, a research biologist for Cascadia Research, an Olympia-based nonprofit which studies marine mammals. “We were just a little nervous that some didn’t show up,” he said. A group of about 10 whales can sometimes stop over in the Whidbey and Camano island areas in mid-February or early March. “The earliest we had one of these whales was the first weekend in March,” he said, with more arriving by mid-March.The core group sometimes is joined by other whales intermittently, he said.

“This is just some sort of in-between pit stop for them,” Calambokidis said. “They’ll often be here for several months. ”The stop is off their migration route, which continues north, he said. The ones that stop have learned that there’s something good to eat here — ghost shrimp. Susan Berta, co-founder of the Orca Network and the Langley Whale Center, said the whales usually remain in the area through May. About six whales have been seen so far, she said. Sightings often are reported in Possession Sound, Saratoga Passage and offshore areas of Island and Snohomish counties, she said.

A bell rings in one of Langley’s parks when whales are spotted. The town hosts an annual Whales Festival, scheduled this year for April 18 and 19. The same group of 10 to 12 whales makes an annual local stop on their migration route from Baja, Mexico, then continues their trek north to the Bering Sea, she said. There’s never been a confirmed sighting of a calf during the time the whales make their local stop, Calambokidis said. They’re predominately males, but three females have been identified in the group. The females “tend to have little more spotty history of showing up here,” he said. “We suspect that may be because in the years they have calves, they don’t make this stop.

”One gray whale seemed to accidentally discover the marine feast of the local ghost shrimp feeding grounds, he said. “He wandered around Puget Sound for a while in the early 1990s before discovering how rich the areas around Island County are for ghost shrimp. “Now he comes back directly to that spot,” Calambokidis said.Cascadia Research plans on doing some study later this month on what proportion of the whales’ total diet while they’re here is ghost shrimp, particularly in the intertidal areas where people harvest the shrimp for bait.The nonprofit is working with the state Department of Natural Resources to investigate how much competition there is between the needs of the gray whales for the shrimp and people’s harvest of the shrimp, he said. Gray whales are thought to live up to 50 years and weigh about 20,000 pounds.

Older female killer whales become pod leaders


This video is called Documentary The Orca – The Intelligent Killer WhaleNational Geographic.

From the Los Angeles Times in the USA:

Menopausal whales lead the group, study says

By Melissa Healy

Sharelines

Mystery solved (maybe): Some females live beyond their reproductive years because their wisdom benefits kin

Menopause: an evolutionary mystery unique to humans, killer whales and short-finned pilot whales

Female killer whales can live past 90. Males rarely survive after 50

What does an ocean-going titaness do after she has the lost the ability to bear young?

Well, for starters, she goes on living–sometimes past the ripe old age of 90, while male killer whales over 50 are dying off in droves. Throughout the animal kingdom, that is unusual enough.

But the menopausal female killer whale does more than survive, says a new study: She “leans in,” becoming an influential leader of younger killer whales, honing the survival skills of her progeny–and their progeny–unencumbered by direct childcare duties of her own.

Quite the opposite of being a burden to her kind, her post-menopausal leadership role seems to make the older female killer whale her species’ evolutionary ace in the hole.

Published in the journal Current Biology, the new research finds that among killer whales, females beyond their reproductive years become habitual leaders of collective movement–generally foraging movement–within their pods. Their position “on point” becomes particularly prominent in lean years, when salmon–the mainstay of the killer whales’ diet–is scarce.

The new findings offer the first evidence that in certain species and under specific circumstances, females who live well beyond their reproductive years “act as repositories of ecological knowledge.”

That helps solve an enduring mystery among biologists: Why–in humans and in two species of toothed whales only–would individuals who no longer propagate their genes continue to survive?

The authors of the study are marine mammal researchers from the universities of York and Exeter in Great Britain and the Center for Whale Research in Washington state. To glean their findings, they analyzed 751 hours of video taken of Southern resident killer whales during annual salmon migrations off the coast of British Columbia and Washington.

The videos were taken over a period of nine years. They captured the movements of pods of killer whales whose populations have been identified and tracked since 1976. That allowed the researchers to determine the age and relatedness of the 102 creatures whose movements they analyzed.

Such detail also allowed the authors to speculate on why post-menopausal survival is so very rare. If post-reproductive females can be such an evolutionary boon for their kin, why do they not survive to serve that function across many species?

Some have suggested that for humans, at least, the post-menopausal survival of women is merely an artifact of better medical care.

Not so, new research–including the killer whales study–suggests. The answer, the authors of this study wrote, may lie in different kinship patterns. Among killer whales, generations of males and females stay together throughout their lives, foraging as a group. As a female ages, her level of genetic relatedness to members of her pod increases.

“Menopause will only evolve,” they wrote, “when inclusive fitness benefits outweigh the costs of terminating reproduction.”

In short, an older female’s continued value to the group may be a function not only of her accumulated knowledge about the whereabouts of food, shelter and predators, but also of her genetic stake in the group’s survival.

That was the case, too, in hunter-gatherer human societies, the authors note. As human societies evolved, women reaching sexual maturity tended to leave the group. As her sons and their many mates and children populated her group, an aging woman’s “relatedness” to that group tended to grow.

In contrast, among other long-lived mammals, sons move off as they reach sexual maturity. So a female becomes less related to the “pod” she stays with as she become older. Under those circumstances, the authors write, she may have sufficient ecological wisdom but not a sufficient level of “relatedness” to her group to ensure her survival beyond the years of reproduction.