Blue whales’ hearts, new research


This 25 November 2019 video from the USA says about itself:

Stanford researchers report first recording of blue whale heart rate.

From Stanford University in the USA:

First recording of a blue whale’s heart rate

November 25, 2019

Summary: With a lot of ingenuity and a little luck, researchers monitored the heart rate of a blue whale in the wild. The measurement suggests that blue whale hearts are operating at extremes — and may limit the whale’s size.

Encased in a neon orange plastic shell, a collection of electronic sensors bobbed along the surface of the Monterey Bay, waiting to be retrieved by Stanford University researchers. A lunchbox-sized speck in the vast waters, it held cargo of outsized importance: the first-ever recording of a blue whale‘s heart rate.

This device was fresh off a daylong ride on Earth’s largest species — a blue whale. Four suction cups had secured the sensor-packed tag near the whale’s left flipper, where it recorded the animal’s heart rate through electrodes embedded in the center of two of the suction feet. The details of this tag’s journey and the heart rate it delivered were published Nov. 25 in Proceedings of the National Academy of Sciences.

“We had no idea that this would work and we were skeptical even when we saw the initial data. With a very keen eye, Paul Ponganis — our collaborator from the Scripps Institution of Oceanography — found the first heart beats in the data,” said Jeremy Goldbogen, assistant professor of biology in the School of Humanities Sciences at Stanford and lead author of the paper. “There were a lot of high fives and victory laps around the lab.”

Analysis of the data suggests that a blue whale’s heart is already working at its limit, which may explain why blue whales have never evolved to be bigger. The data also suggest that some unusual features of the whale’s heart might help it perform at these extremes. Studies like this add to our fundamental knowledge of biology and can also inform conservation efforts.

“Animals that are operating at physiological extremes can help us understand biological limits to size,” said Goldbogen. “They may also be particularly susceptible to changes in their environment that could affect their food supply. Therefore, these studies may have important implications for the conservation and management of endangered species like blue whales.”

Penguins to whales

A decade ago, Goldbogen and Ponganis measured the heart rates of diving emperor penguins in Antarctica’s McMurdo Sound. For years after, they wondered whether a similar task could be accomplished with whales.

“I honestly thought it was a long shot because we had to get so many things right: finding a blue whale, getting the tag in just the right location on the whale, good contact with the whale’s skin and, of course, making sure the tag is working and recording data,” said Goldbogen.

The tag performed well on smaller, captive whales, but getting it near a wild blue whale’s heart is a different task. For one thing, wild whales aren’t trained to flip belly-up. For another, blue whales have accordion-like skin on their underside that expands during feeding, and one such gulp could pop the tag right off.

“We had to put these tags out without really knowing whether or not they were going to work,” recalled David Cade, a recent graduate of the Goldbogen Lab who is a co-author of the paper and who placed the tag on the whale. “The only way to do it was to try it. So we did our best.”

Cade stuck the tag on his first attempt and, over time, it slid into a position near the flipper where it could pick up the heart’s signals. The data it captured showed striking extremes.

When the whale dove, its heart rate slowed, reaching an average minimum of about four to eight beats per minute — with a low of two beats per minute. At the bottom of a foraging dive, where the whale lunged and consumed prey, the heart rate increased about 2.5 times the minimum, then slowly decreased again. Once the whale got its fill and began to surface, the heart rate increased. The highest heart rate — 25 to 37 beats per minutes — occurred at the surface, where the whale was breathing and restoring its oxygen levels.

An elastic heart

This data was intriguing because the whale’s highest heart rate almost outpaced predictions while the lowest heart rate was about 30 to 50 percent lower than predicted. The researchers think that the surprisingly low heart rate may be explained by a stretchy aortic arch — part of the heart that moves blood out to the body — which, in the blue whale, slowly contracts to maintain some additional blood flow in between beats. Meanwhile, the impressively high rates may depend on subtleties in the heart’s movement and shape that prevent the pressure waves of each beat from disrupting blood flow.

Looking at the big picture, the researchers think the whale’s heart is performing near its limits. This may help explain why no animal has ever been larger than a blue whale — because the energy needs of a larger body would outpace what the heart can sustain.

Now, the researchers are hard at work adding more capabilities to the tag, including an accelerometer, which could help them better understand how different activities affect heart rate. They also want to try their tag on other members of the rorqual whale group, such as fin whales, humpbacks and minke whales.

“A lot of what we do involves new technology and a lot of it relies on new ideas, new methods and new approaches,” said Cade. “We’re always looking to push the boundaries of how we can learn about these animals.”

Additional Stanford co-authors include graduate students Max Czapanskiy, James Fahlbusch, William Gough and Shirel Kahane-Rapport and postdoctoral fellow Matt Savoca. Ponganis is senior author of the paper and additional co-authors are from Cascadia Research Collective; the University of California, Santa Cruz; and Scripps Institution of Oceanography. Goldbogen is also a member of Stanford Bio-X.

This research was funded by the Office of Naval Research, a Terman Fellowship from Stanford University and the John B. McKee Fund at Scripps Institution of Oceanography.

Humpback whales, orcas off Russia


This 19 November 2019 video says about itself:

In the sea of Okhotsk, off Russia’s eastern coast, two types of whales are making a comeback: humpback whales and orcas. Both are drawn here in the summer to feast on the plentiful herring.

Humpback whales in the South Atlantic have recovered from near-extinction. A new count shows the population off Brazil went from about 450 in the 1950s to 25,000 now: here.

NATO kills 18 Baltic Sea porpoises


This 6 July 2018 video says about itself:

With only 500 animals left, the Baltic harbor porpoises have been declared critically endangered. Being killed as bycatch in fishing nets is the major threat for the animals, yet fishing is still permitted, even in Marine Protected Areas. In Sea Shepherd’s Perkunas campaign, the crew of the M/V Emanuel Bronner documented and monitored deadly gillnets in protected areas of the Baltic Sea. But accidental death in fishing nets is not the only human-caused threat for these animals.

Eutrophication, underwater noise, marine debris, overfishing, and bottom trawling are also damaging the Baltic Sea ecosystem, affecting both harbor porpoises and the local populations that depend on it.

Read the full commentary by Perkunas campaign leader, Reinhard Grabler here.

Translated from Dutch NOS TV:

’18 porpoises dead after naval exercise in Germany’

A German environmental organization says that eighteen porpoises were killed during a military war game in the Baltic Sea. That, they say, have happened during a NATO war game in September. As part of that mission, the German navy blew up 42 British mines, German media report. Porpoises are regarded as a protected species in Europe.

The war game was training to defuse sea mines. In addition, real ground mines from the First World War, left behind by the British, were blown up.

An analysis of that action shows that every explosion left a crater 5 by 1.5 meters deep and that animals and plants were destroyed in a radius of 10 to 30 meters.

Nature destroyed

According to the environmental organization NABU and the political party The Greens, the Ministry of Defense has ignored nature conservation law. The Greens estimate that up to 110,000 square meters of nature have been destroyed.

According to Nabu, NATO blew up the mines right in the nursery grounds for young porpoises.

NABU map of porpoises killed by the war game

More than forty ships from 18 countries, including the Netherlands, took part in the exercise. …

Tunnel to Denmark

The NATO mission took place at an area where there are plans for the construction of a tunnel. The connection to be made must connect the German island of Fehmarn with the Danish Lolland. The construction of the tunnel costs around € 7.4 billion and is largely paid for by Denmark.

Critics point out that there is more ammunition in the Fehmarnbelt strait. After the Second World War, hundreds of thousands of tons of bombs, rockets and mines were dumped in the Baltic Sea and North Sea. Environmental organizations have been pointing out for some time that rust-causing substances end up in seawater. According to environmental organization Nabu there is a total of 1.6 million tons of ammunition in the North Sea and Baltic Sea.

New fin whale subspecies discovery


This 29 January 2012 video from the USA says about itself:

Fin Whale Watching with the Aquarium of the Pacific off Long Beach, California

The Aquarium of the Pacific has seen a record number of Gray whales, endangered Fin whales, Orcas and Dolphins off the coast of Long Beach on their whale watching excursions this Winter (January 2012). The Aquarium invited MomsLA out for a chance to see what we could see and it was amazing: we saw two giant pods of Dolphins and a pod of endangered Fin Whales. Later that day the Aquarium saw a pod of Orcas and a pod of Gray whales as well.

From NOAA Fisheries West Coast Region in the USA:

Genetics reveal Pacific subspecies of fin whale

New findings highlight diversity of marine mammals

October 28, 2019

e northern Pacific Ocean as a separate subspecies, reflecting a revolution in marine mammal taxonomy as scientists unravel the genetics of enormous animals otherwise too large to fit into laboratories.

“The increasing study of cetacean genetics is revealing new diversity among the world’s whales and dolphins that has not been previously recognized,” said Eric Archer, a geneticist at NOAA Fisheries’ Southwest Fisheries Science Center (SWFSC) in La Jolla, California. Archer is the lead author of the identification of the new subspecies of fin whale.

“There’s definitely more diversity out there than has been on the books,” he said. “There has been a wave of progress in cetacean taxonomy.”

Fin whales are the second-largest whale on earth and the fastest whales in the ocean, which made them one of the last whale species hunted to the edge of extinction. Whalers killed about 46,000 fin whales in the North Pacific Ocean from 1947 to 1987. They are also one of the least known large whale species. They mainly roam the open ocean, farther from coastlines where they might be seen and studied more easily.

Scientists from NOAA Fisheries, Ocean Associates Inc., Cascadia Research Collective, Tethys Research Institute, and Universidad Autónoma de Baja California Sur, identified the new subspecies. Their findings were published in an article in the Journal of Mammalogy, naming it Balaenoptera physalus velifera, which means “carrying a sail” in Latin.

“We don’t get a lot of (genetic) material from them,” Archer said. However, advancing technologies allowed Archer and his colleagues to extract the detail they needed from samples at the SWFSC. The center’s Marine Mammal and Turtle Molecular Research Sample Collection is one of the largest collections of marine mammal genetic material in the world. They obtained additional samples from museums and other collections.

Bypassing the Skulls

Traditional taxonomy — the division of biological variation into recognized species and subspecies — involves comparing telltale parts of the skeleton such as the skull. For whales, this may weigh hundreds of pounds. Few institutions can amass a large enough collection to compare different individuals from around the world.

“Fin whales measure 60 to 70 feet long and their skulls are around 15 feet long,” Archer said. “Just housing a couple takes a lot of room.”

Increasingly powerful genetic technologies now allow scientists to compare genes instead of skeletons. They extract DNA from tissue samples the size of a pencil eraser obtained from whales in the field.

“It’s the only realistic way to do this, because you cannot get enough examples to determine the difference through morphology alone,” Archer said. As they have looked more closely at the genetic patterns of whales around the world, scientists have discovered much more complex differences between them.

“Instead of digging through museum storage facilities for skulls to describe species or subspecies, genetic data unlock our ability to describe unique populations of whales across the globe,” said research biologist Barbara Taylor, leader of the SWFSC’s Marine Mammal Genetics Program. “It is a new way of looking at these animals.”

Telltale Differences in the DNA

Comparing the DNA from fin whales in the Pacific and the Atlantic oceans showed the scientists that they have been separated for hundreds of thousands of years. They also could assign individual fin whale samples to their ocean of origin using the genetic data. This is further evidence that they are separate and distinct subspecies.

Genetic research by NOAA Fisheries scientists has also revealed new details of other whales, including a new species of Baird’s beaked whale. It may also help determine whether a recently documented type of killer whale off South America represents a new species.

Similar genetic details can also help tailor protections for threatened or endangered whales, because the Endangered Species Act recognizes separate subspecies. That means that managers can target ESA safeguards for those subspecies that need it even when others may have recovered. This could make conservation efforts more efficient and effective.

About 14,000 to 18,000 fin whales in the northern Pacific Ocean will be affected by the new subspecies designation. NOAA Fisheries has documented that their numbers are increasing.

“There are other new species and subspecies that we are learning about thanks to the technology that has made this possible,” Archer said. “It is changing the field.”

Dead whale feeds deep-sea animals, videos


This 16 October 2019 video says about itself:

Whale Fall Actively Devoured by Scavengers at Davidson Seamount| Nautilus Live

During the final dive of this year’s Nautilus expedition season, our team discovered a whale fall while exploring Davidson Seamount off central California’s coast with researchers from Monterey Bay National Marine Sanctuary. The skeletal remains of the whale lying on its back are estimated to be 4-5 meters long. The team is working to identify the species, but it is confirmed to be a baleen whale as indicated by baleen remaining along the whale’s jawbones.

While evidence of whale falls have been observed to remain on the seafloor for several years, this appears to be a relatively recent fall with baleen, blubber, and some internal organs remaining. The site also exhibits an interesting mid-stage of ecological succession, as both large scavengers like eelpouts are still stripping the skeleton of blubber, and bone-eating Osedax worms are starting to consume lipids (fats) from the bones. Other organisms seen onsite include crabs, grenadier, polychaetes, and deep-sea octopus.

This 17 October 2019 video is the sequel. It says about itself:

The banquet continues! Yesterday we made a surprise baleen whale fall discovery that viewers around the globe watched alongside the Nautilus team in Monterey Bay National Marine Sanctuary. Get a close up look at some of the scavenging diners including eelpouts, octopus, and polychaete worms–like the bone-eating Osedax worms that carpet the whale’s bones in a red fringe.

Good humpback whale news


This 15 February 2019 video from the Cook Islands says about itself:

This humpback whale started acting strangely towards a diver, but was it really just trying to save her from a nearby tiger shark?

From the University of Washington in the USA:

Humpback whale population on the rise after near miss with extinction

October 21, 2019

Summary: A new study finds that the western South Atlantic humpback population has grown to 25,000 whales. Researchers believe this new estimate is now close to pre-whaling numbers.

A population of humpback whales in the South Atlantic has rebounded from the brink of extinction.

Intense pressure from the whaling industry in the 20th century saw the western South Atlantic population of humpbacks diminish to only 450 whales. It is estimated that 25,000 whales were caught over approximately 12 years in the early 1900s.

Protections were put in place in the 1960s as scientists noticed worldwide that populations were declining. In the mid-1980s, the International Whaling Commission issued a moratorium on all commercial whaling, offering further safeguards for the struggling population.

A new study co-authored by Grant Adams, John Best and André Punt from the University of Washington’s School of Aquatic and Fishery Sciences shows the western South Atlantic humpback (Megaptera novaeangliae) population has grown to 25,000. Researchers believe this new estimate is now close to pre-whaling numbers.

The findings were published Oct. 16 in the journal Royal Society Open Science.

“We were surprised to learn that the population was recovering more quickly than past studies had suggested,” said Best, a UW doctoral student.

The study follows a previous assessment conducted by the International Whaling Commission between 2006 and 2015. Those findings indicated the population had only recovered to about 30% of its pre-exploitation numbers. Since that assessment was completed, new data has come to light, providing more accurate information on catches — including struck-and-lost rates — and genetics and life-history.

“Accounting for pre-modern whaling and struck-and-lost rates where whales were shot or harpooned but escaped and later died, made us realize the population was more productive than we previously believed,” said Adams, a UW doctoral student who helped construct the new model.

By incorporating detailed records from the whaling industry at the outset of commercial exploitation, researchers have a good idea of the size of the original population. Current population estimates are made from a combination of air- and ship-based surveys, along with advanced modeling techniques.

The model built for this study provides scientists with a more comprehensive look at the recovery and current status of the humpback population. The authors anticipate it can be used to determine population recovery in other species in more detail as well.

“We believe that transparency in science is important,” said Adams. “The software we wrote for this project is available to the public and anyone can reproduce our findings.”

Lead author Alex Zerbini of the NOAA Alaska Fisheries Science Center’s Marine Mammal Laboratory stressed the importance of incorporating complete and accurate information when conducting these assessments, and providing population assessments without biases. These findings come as good news, he said, providing an example of how an endangered species can come back from near extinction.

“Wildlife populations can recover from exploitation if proper management is applied,” Zerbini said.

The study also looks at how the revival of South Atlantic humpbacks may have ecosystem-wide impacts. Whales compete with other predators, like penguins and seals, for krill as their primary food source. Krill populations may further be impacted by warming waters due to climate change, compressing their range closer to the poles.

“Long-term monitoring of populations is needed to understand how environmental changes affect animal populations,” said Zerbini.

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: here.

Spacecraft helps finding beached whales


This 10 February 2017 video says about itself:

New Zealand volunteers formed a human chain in the water at a remote beach on Friday as they raced to save dozens of whales after more than 400 of the creatures beached themselves.

From the British Antarctic Survey:

Stranded whales detected from space

October 17, 2019

A new technique for analysing satellite images may help scientists detect and count stranded whales from space. Researchers tested a new detection method using Very High Resolution (VHR) satellite images from Maxar Technologies of the biggest mass stranding of baleen whales yet recorded. It is hoped that in the future the technique will lead to real-time information as stranding events happen.

The study, published this week in the journal PLoS ONE by scientists from British Antarctic Survey and four Chilean research institutes, could revolutionise how stranded whales, that are dead in the water or beached, are detected in remote places.

In 2015, over 340 whales, most of them sei whales, were involved in a mass-stranding in a remote region of Chilean Patagonia. The stranding was not discovered for several weeks owing to the remoteness of the region. Aerial and boat surveys assessed the extent of the mortality several months after discovery.

The researchers studied satellite images covering thousands of kilometres of coastline, which provided an early insight into the extent of the mortality. They could identify the shape, size and colour of the whales, especially after several weeks when the animals turned pink and orange as they decomposed. A greater number of whales were counted in the images captured soon after the stranding event than from the local surveys.

Many coastal nations have mammal stranding networks recognising that this is a crucial means to monitor the health of the local environment, especially for providing first notice of potential marine contamination and harmful algal blooms.

Author and whale biologist Dr Jennifer Jackson at British Antarctic Survey says:

“The causes of marine mammal strandings are poorly understood and therefore information gathered helps understand how these events may be influenced by overall health, diet, environmental pollution, regional oceanography, social structures and climate change.

“As this new technology develops, we hope it will become a useful tool for obtaining real-time information. This will allow local authorities to intervene earlier and possibly help with conservation efforts.”

Lead author, remote sensing specialist Dr Peter Fretwell at British Antarctic Survey says:

“This is an exciting development in monitoring whales from space. Now we have a higher resolution ‘window’ on our planet, satellite imagery may be a fast and cost-effective alternative to aerial surveys allowing us to assess the extent of mass whale stranding events, especially in remote and inaccessible areas.”