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.”

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Mother right whales ‘whisper’ to calves


This 2016 video is called North Atlantic Right Whales.

From Syracuse University in the USA:

Hush, little baby: Mother right whales ‘whisper’ to calves

October 9, 2019

Summary: A recent study explores whether right whale mother-calf pairs change their vocalizations to keep predators from detecting them.

On June 20, a whale that researchers had named Punctuation was found dead in the Gulf of Saint Lawrence, a busy international shipping channel. Punctuation — so named for her comma-shaped scars — was a North Atlantic right whale, a species severely threatened by human activity. With only 420 left in the world, it is one of the most endangered whale species. Any additional death, especially of a reproductive female, puts the species further in jeopardy.

News of this death was particularly difficult for Syracuse University biology Professor Susan Parks, who had studied and written about Punctuation in a paper exploring acoustic communication among North Atlantic right whales.

This study was recently published in Biology Letters by Parks, along with Dana Cusano, also of Syracuse; Sofie Van Parijs, Ph.D., of the NOAA Fisheries, Northeast Fisheries Center; and Professor Douglas Nowacek of Duke University. It sheds new light on behavior between mother and calf North Atlantic right whales.

Parks has studied North Atlantic right whale behavior and acoustic communication since 1998. She leads the Bioacoustics and Behavioral Ecology Lab at Syracuse University, whose researchers study the sounds animals make, including those of right whales.

The recent study in Biology Letters explores whether mother-calf pairs change their vocalizations to keep predators from detecting them. Right whales, due to their large size, have few natural predators and are only vulnerable to orca or sharks when they are young calves.

One way to reduce the risk of predation for young calves would be for mothers to hide their young. Because the water is murky, predators are most likely to find right whales by eavesdropping on their communication signals. Any hiding by a mother and her calf would have to be acoustic — that is, producing little or no sound.

Parks and her collaborators studied whether mothers with young calves stop using the usual loud, long-distance communication signals to talk to other right whales. To collect the data, the team listened to whale sounds in the North Atlantic right whale calving grounds off the coasts of Florida and Georgia, using small recording tags attached to the whales by suction cups. Collecting data from mother-calf pairs, and from other juvenile and pregnant whales in the habitat that have less need to hide, the researchers sought to determine if mothers were modifying their behavior to be less conspicuous.

The Biology Letters study shows that mother-calf pairs drastically reduce the production of these common, louder sounds but they also produced a very soft, short, grunt-like sound. These grunts, previously unknown in right whales, were only detectable by the attached recording devices and were not audible more than a short distance from the mother-calf pair.

“These sounds can be thought of almost like a human whisper,” Parks says. “They allow the mother and calf to stay in touch with each other without advertising their presence to potential predators in the area.”

“Right whales face a number of challenges, including a very low number of calves born in recent years combined with a number of deaths from collisions with large ships or entanglement in heavy fishing gear,” Parks says. “There have been 30 confirmed right whale deaths in the past three years, including the recent death of Punctuation in June of this year. There are still so many things we don’t know about their behavior, and it is my hope that studies like these will help to improve efforts for their conservation.”

Weighing whales with drones


This 2010 video says about itself:

Breeding Southern Right Whales | Attenborough | Life of Mammals | BBC

The Southern Right Whale is an enormous creature – in more ways than one. In this clip, a group of fertile males surround a female who is not initially receptive in order to mate. With a twelve foot long penis and testes that weigh a ton, picking the right moment is critically important.

From the British Ecological Society:

Researchers use drones to weigh whales

October 2, 2019

By measuring the body length, width and height of free-living southern right whales photographed by drones, researchers were able to develop a model that accurately calculated the body volume and mass of the whales.

Because of their large size and aquatic life, previously the only way to obtain data on the body mass of whales was to weigh dead or stranded individuals.

The innovative method can be used to learn more about the physiology and ecology of whales, “Knowing the body mass of free-living whales opens up new avenues of research. We will now be able to look at the growth of known aged individuals to calculate their body mass increase over time and the energy requirements for growth. We will also be able to look at the daily energy requirements of whales and calculate how much prey they need to consume.” said Assistant Professor Fredrik Christiansen from Aarhus Institute of Advanced Studies in Denmark and lead author of the study.

Dr. Michael Moore, a Senior Scientist at the Woods Hole Oceanographic Institution and co-author said: “Weight measurements of live whales at sea inform how chronic stressors affect their survival and fecundity, as well as enabling accurate sedative dosing of animals entangled in fishing gear that are aversive to disentanglement attempts.”

The model is already being used to assess the impacts of kelp gull harassment on the health and survival of southern right whale calves. Dr. Mariano Sironi and Dr. Marcela Uhart from the Southern Right Whale Health Monitoring Program and co-authors, emphasized “The use of drones to estimate whale weight and condition, as well as to individually track calves while they grow beside their mothers, has been a real breakthrough in our investigation.”

“In the past we’ve had to rely entirely upon stranded carcasses which added all sorts of uncertainties to our studies.”

The model also allowed the researchers to collaborate with the Digital Life Project at the University of Massachusetts, USA to first recreate a 3D mesh of the whale, and then to work with CG artist Robert Gutierrez to recreate the full-colour 3D model of the right whale. These models can be used for both scientific purposes, such as studying movement, as well as for educational uses.

By adjusting the parameters of the model, the approach could be used to estimate the size of other marine mammals where alternative, more invasive, methods aren’t feasible or desirable.

Baleen whales, which include species like the blue whale, are the largest animals on this planet, with body mass being central to their success as an animal group. However, data on their size has historically been limited to dead specimens, with most samples coming from whaling operations, accidental fisheries bycatch or beach strandings.

Collecting data on dead whales has limitations such as being unable to collect longitudinal data over a whale’s life span and inaccuracies from physical distortion of carcasses caused by bloating and deflation.

Assistant Professor Christiansen explained that “The difficulty in measuring body mass reliably in free-living whales, has prevented the inclusion of body mass in many studies in ecology, physiology and bioenergetics. This novel approach will now make it possible to finally include this central variable into future studies of free-living whales.”

To calculate the body volume and mass of southern right whales the researchers first took aerial photos of 86 individuals off the coast of Península Valdés, Argentina. The clear waters and the large number of whales that gather there every winter for breeding made it an ideal place to collect high quality images of both the dorsal and lateral sides of the whales. From these they were able to obtain length, width and height measurements.

These measurements could then be used to accurately model the body shape and volume of the whales. “We used this model to estimate the body volume of whales caught in scientific whaling operations, for which body girth and mass was known. From these estimates of body volume, we could then calculate the density of the whales, which we in turn could use to estimate the mass of free-living whales photographed by our drones”, said Christiansen.

Although the model yielded body mass estimates to a high-level of accuracy, there were some limitations due to the relative proportion of different tissues in baleen whales. Christiansen said, “We had to assume a constant body density of the whales, which is not realistic as the proportion of different body tissues (fat, muscle etc.) changes seasonally as the whales deposit or lose body condition.”

How blue and fin whales feed, new research


This 2014 video says about itself:

Sri Lanka provides sanctuary to one of the greatest Blue Whale colonies in the world.

Blue Whales are the largest animal our planet has ever known. Their tongues alone weigh more than an elephant. Their hearts are the size of a car. Despite all that, we really know very little about the magnificent Blue Whale.

From Oregon State University in the USA:

How long does a whale feed? New data gives insight into blue and fin whale behavior

September 11, 2019

Researchers using electronic tags were able to monitor blue and fin whales off the coast of Southern California over multiple weeks, providing new insight into the feeding behaviors of the two largest whale species. The researchers also found evidence of differences in the feeding intensity and habitat use of males and females of both species.

“The information collected with these tags gives us a good description of the scale of whales’ feeding behavior over periods of hours, days and weeks, which is something we’ve not been able to do before,” said Ladd Irvine, a senior faculty research assistant in Oregon State University’s Marine Mammal Institute and the study’s lead author.

The whales fed mostly during the day, usually in short bursts lasting one to two hours, but would also feed continuously throughout the daytime, and in rare circumstances for an entire day.

“We were able to quantify feeding bouts, which are periods of uninterrupted feeding, and found that the duration of feeding bouts correlated with another measure of feeding success — the number of prey capture events, known as feeding lunges,” Irvine said. “That means the whales stayed longer in areas where they fed more. This allowed us to make inferences about the profitability of feeding patches, as whales should stay in an area and feed longer where prey is abundant and move on when prey becomes scarce.”

The findings, which were published this week in the journal Frontiers in Ecology and Evolution, could have implications for managing populations of blue and fin whales, both of which are listed as endangered in the United States.

In 2014 and 2015, researchers tagged eight blue and five fin whales off the coast of Point Mugu and San Miguel Island in Southern California. Both species frequent the area, feasting on krill.

Prior whale monitoring efforts had relied solely on location tracking, which tells researchers where the whales travel, but not what happens along the way. The tags used in this study, developed at Oregon State in collaboration with Wildlife Computers Inc., included GPS for movement monitoring as well as the ability to record information about the whales’ behavior every second while they were on the move. Accelerometers and other sensors on the tags measured lunge-feeding behavior as well as frequency and depth of dives.

“The hardest thing about studying whales is that you can’t really follow them when they dive below the surface” said Irvine, who is also a doctoral student in the OSU College of Agricultural Sciences’ Department of Fisheries and Wildlife. “The data collected from these tags give us unprecedented detail about what whales are doing over a longer time period than was previously possible.”

Tags remained on the blue whales an average of 22 days and on the fin whales about 14 days. It’s unclear why the tags came off the fin whales more quickly, but it could have to do with their movement and faster speed in the water, Irvine said.

The researchers found that both species of whales had similar feeding bout characteristics. During an average feeding bout, blue whales made 24 dives over a period of about 3.3 hours, while fin whales made 19 dives over 2.7 hours. The similarities are not surprising, the researchers said, as the two species are similar in size and feed in the same way. Slight differences observed may be due to preferences in terms of patch characteristics or prey type.

“This study represents a significant leap forward in our knowledge of whale foraging ecology,” said Daniel Palacios, who holds the Endowed Faculty in Whale Habitats position at the Marine Mammal Institute and is a co-author of the paper.

“By collecting data from individual whales over multiple days and weeks, we were able to obtain large amounts of new information about how feeding intensity evolves and changes in time and space, at scales that are relevant to ecology as well as management,” he said. “We were able to answer questions like how long does a whale feed? What is the size of a feeding patch? How far does a whale need to move before it finds the next patch? Do females and males feed at the same intensity? It may seem surprising, but studying whales is enormously challenging and we lacked much of this information.”

But feeding might not be the only thing on the whales’ minds, as the researchers also found differences in movements between tagged males and females of both species.

“The males made big loops offshore of Southern California, while the females stuck closer to shore. Those routes may be related somehow to breeding behavior, and could have implications in terms of exposure to human activities if whales of one sex are more likely to be encountered in specific parts of busy Southern California waters,” Irvine said.

“While the results are exciting, our conclusions about the behaviors of whales from this initial set of data from 13 animals should be viewed as preliminary,” he said. “These data are an incredibly rich description of the tagged whales’ behavior, but they ultimately represent a relatively small number of individuals, occupying a portion of their overall range.”

Ideally, similar data would be collected again from different locations or different whales to determine if the observed feeding and other behavior patterns are representative of the broader populations, he said.

“Nevertheless, this information is a huge addition to our understanding of blue and fin whale feeding ecology,” Irvine said. “Does what we saw with these individuals hold up as we continue to study them in other places and seasons? That’s a question still to be determined. We’re still just scratching the surface of our understanding of whale behavior.”

New beaked whale species discovery in Japan


This 7 November 2016 video says about itself:

St George, Alaska Berardius New Beaked Whale

For over 60 years, Japanese whalers have observed an unusual form of beaked whale in northern waters. Called Kurotsotchi or “raven whale”, biologists considered it possibly a dark form of Baird’s beaked whale, Berardius bairdi. An international team of scientists and naturalists contributed specimens and observations, and, recently, Dr. Phil Morin examined DNA of this dark form. Data point to a new species of whale!

This slideshow chronicles the St. George Island, Alaska community’s role in securing the “8th whale”. This specimen provided both morphological and DNA data critical for advancing the discovery of the new species of beaked whale in the Berinigian region.

From Hokkaido University in Japan:

New whale species discovered along the coast of Hokkaido

September 3, 2019

A new beaked whale species Berardius minimus, which has been long postulated by local whalers in Hokkaido, Japan, has been confirmed.

In a collaboration between the National Museum of Nature and Science, Hokkaido University, Iwate University, and
the United States National Museum of Natural History, a beaked whale species which has long been called Kurotsuchikujira (black Baird’s beaked whale) by local Hokkaido whalers has been confirmed as the new cetacean species Berardius minimus (B. minimus).

Beaked whales prefer deep ocean waters and have a long diving capacity, making them hard to see and inadequately understood. The Stranding Network Hokkaido, a research group founded and managed by Professor Takashi F. Matsuishi of Hokkaido University, collected six stranded un-identified beaked whales along the coasts of the Okhotsk Sea.

The whales shared characteristics of B. bairdii (Baird’s beaked whale) and were classified as belonging to the same genus Berardius. However, a number of distinguishable external characteristics, such as body proportions and color, led the researchers to investigate whether these beaked whales belong to a currently unclassified species.

“Just by looking at them, we could tell that they have a remarkably smaller body size, more spindle-shaped body, a shorter beak, and darker color compared to known Berardius species,” explained Curator Emeritus Tadasu K. Yamada of the National Museum of Nature and Science from the research team.

In the current study, the specimens of this unknown species were studied in terms of their morphology, osteology, and molecular phylogeny. The results, published in the journal Scientific Reports, showed that the body length of physically mature individuals is distinctively smaller than B. bairdii (6.2-6.9m versus 10.0m). Detailed cranial measurements and DNA analyses further emphasized the significant difference from the other two known species in the genus Berardius. Due to it having the smallest body size in the genus, the researchers named the new species B. minimus.

“There are still many things we don’t know about B. minimus,” said Takashi F. Matsuishi. “We still don’t know what adult females look like, and there are still many questions related to species distribution, for example. We hope to continue expanding what we know about B. minimus.”

Local Hokkaido whalers also refer to some whales in the region as Karasu (crow). It is still unclear whether B. minimus (or Kurotsuchikujira) and Karasu are the same species or not, and the research team speculate that it is possible Karasu could be yet another different species.

This study was conducted in collaboration with multiple institutions. Dr. Shino Kitamura and Dr. Shuichi Abe of Iwate University carried out the DNA analyses while Dr. Tadasu K. Yamada and Dr. Yuko Tajima of the National Museum of Nature and Science made osteological specimens, morphological observations and detailed measurements to depict systematic uniqueness. Dr. Takashi F. Matsuishi and Dr. Ayaka Matsuda of Hokkaido University made the multivariate analyses. Dr. James G. Mead of Smithsonian Institution contributed to discussions related to systematic comparison.

Bottlenose dolphin mother adopts melon-headed whale calf


This 5 August 2019 video says about itself:

Dolphin Mom Adopts a Calf From a Different Species | Nat Geo Wild

A bottlenose dolphin mother off the coast of French Polynesia was spotted caring for a melon-headed whale.