What’s killing killer whales? Orca report covering a decade of necropsies identifies threats — ScienceDaily

Pathology reports on more than 50 killer whales stranded over nearly a decade in the northeast Pacific and Hawaii show that orcas face a variety of mortal threats — many stemming from human interactions.

A study analyzing the reports was published today in the journal PLOS ONE. The study findings indicate that understanding and being aware of each threat is critical for managing and conserving killer whale populations. It also presents a baseline understanding of orca health.

The study was conducted by a team of marine mammal and orca specialists led by the British Columbia Ministry of Agriculture and coordinated through the SeaDoc Society, a Washington-based program of the University of California, Davis’ School of Veterinary Medicine. The lead author, Dr Stephen Raverty, and coauthor, Dr John Ford, are adjunct professions at the University of British Columbia Institute of Oceans and Fisheries and Department of Zoology, respectively.

The whales

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New research shows even small ships pose deadly threat to North American right whales

right whale
A female North Atlantic right whale with her calf. Credit: Public Domain

It has long been known that ship strikes involving large vessels pose one of the greatest threats to North Atlantic right whales, whose coastal habitats and tendency to stay close to the water’s surface make them vulnerable to such deadly collisions.

New research by Dal scientists suggests that the endangered animals can also suffer fatal injuries if struck by small boats or by large vessels travelling at slow speeds.

“We’ve shown clearly that small vessels can be a threat to whales. We’ve shown that very light, but fast-moving vessels like trans-oceanic racing sailboats can cause potentially lethal injuries to whales, so it means if you’re in a vessel on the ocean, you may be a threat to these animals,” says Sean Brillant, an adjunct in the Department of Oceanography.

“We also showed that there is indeed no safe

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Blue whales return to sub-Antarctic island of South Georgia after near local extinction — ScienceDaily

An international research team led by UK scientists has revealed the return of critically endangered Antarctic blue whales to the sub-Antarctic island of South Georgia, 50 years after whaling all but wiped them out. The new study follows recent research that humpback whales are also returning to the region.

The discovery, based on analysis of 30 years’ worth of sightings, photographs and underwater sound recordings, is crucial evidence in learning how the species is recovering following a ban on commercial whaling in the 1960s. The findings are published today (19 November) in the journal Endangered Species Research.

Blue whales were abundant off South Georgia before early 20th century industrial whaling between 1904 and 1971 killed 42,698 of them there. Most of these were killed before the mid-1930s.

The species all but vanished from the region — dedicated whale surveys from ships off South Georgia resulted in only a single

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Bitcoin Whales’ Ownership Concentration Is Rising During Rally

(Bloomberg) — A lot of theories have emerged on why Bitcoin has skyrocketed almost 60% in the past month, with most heralding widespread adoption by institutions and individuals.The fact remains that there’s nothing widespread about Bitcoin ownership.

A few large holders commonly referred to as whales continue to own most Bitcoin. About 2% of the anonymous ownership accounts that can be tracked on the cryptocurrency’s blockchain control 95% of the digital asset, according to researcher Flipside Crypto.

“The story is that as the price has surged upwards lately, the concentration in the hands of the largest accounts has also risen” since July, said Eric Stone, head of data science at Flipside.

chart, line chart, histogram: Percentage of Accounts Owning 95% of Bitcoin Supply

© Bloomberg
Percentage of Accounts Owning 95% of Bitcoin Supply

A large holder can have an outsized impact on the still highly illiquid market. One trade can often move the coin’s price significantly. That continues to leave small investors

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How Surfing Suckerfish Stick to Whales | Smart News

Remoras are known for being the ocean’s hitchhikers because they spend most of their lives physically attached to hosts like whales, sharks and large fish. But these fish aren’t just mooching rides from their chauffeurs—the pair shares a mutually beneficial relationship. Hosts have potentially dangerous parasites removed while remoras get free meals, protection from predators and higher chances of meeting mates.

Scientists have long marveled at suckerfishes’ ability to stick to their hosts via a powerful suction disk on their heads, though they knew little about how it worked. Now, an accidental discovery has revealed the secret behind how remoras catch a ride.

Stanford marine biologist Jeremy Zucker had set out to learn about the feeding habits of blue whales in 2014 by attaching video cameras to their backs, reports Cara Giaimo for the New York Times. While reviewing the footage, he was surprised to see remoras skittering across

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Genome and satellite technology reveal recovery rates and impacts of climate change on southern right whales

Genome and satellite technology reveal recovery rates and impacts of climate change on southern right whales
Credit: University of Auckland tohorā research team, Department of Conservation permit DJI

After close to a decade of globe-spanning effort, the genome of the southern right whale has been released this week, giving us deeper insights into the histories and recovery of whale populations across the southern hemisphere.

Up to 150,000 southern right whales were killed between 1790 and 1980. This whaling drove the global population from perhaps 100,000 to as few as 500 whales in 1920. A century on, we estimate there are 12,000 southern right whales globally. It’s a remarkable conservation success story, but one facing new challenges.

The genome represents a record of the different impacts a species has faced. With statistical models we can use genomic information to reconstruct historical population trajectories and patterns of how species interacted and diverged.

We can then link that information with historical habitat and climate patterns. This look back into

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How Suckerfish Surf Across Blue Whales Without Falling Off

In 2014, Jeremy Goldbogen, a marine biologist at Stanford University, stuck video cameras on the backs of blue whales, hoping to learn more about their feeding habits. When he retrieved the footage, he realized he had been photobombed. Dozens of Remora australis were treating his research subjects like dance floors, skimming and twisting across them — even as the whales swam at high speeds.

They were “cruising all over the surface” of the whales, he said. “We were not expecting that at all.”

Remoras — also known as suckerfish or whalesuckers — are strange, even for fish. They hitch rides with cetaceans, sharks and other larger creatures of the deep, attaching to them by means of a “sucking disc” that sits on their head like a flat, sticky hat. They then act as a kind of mobile pit crew, eating dead skin, parasites and leftovers off their hosts’ bodies

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Secret surfing life of remoras hitchhiking on blue whales — ScienceDaily

Sticking to the bodies of sharks and other larger marine life is a well-known specialty of remora fishes (Echeneidae) and their super-powered suction disks on their heads. But a new study has now fully documented the “suckerfish” in hitchhiking action below the ocean’s surface, uncovering a much more refined skillset that the fish uses for navigating intense hydrodynamics that come with trying to ride aboard a 100-ft. blue whale (Balaenoptera musculus).

In a study published Oct. 28 in the Journal of Experimental Biology, an international team of researchers studying the unique fluid environments of blue whales traveling off the coast of Palos Verdes and San Diego, CA has reported capturing the first-ever continuous recording of remora behavior on a host organism, using advanced biosensing tags with video recording capabilities.

The study shows the secrets behind the remora fish’s success in hitchhiking aboard baleen whales more than 30 times their

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