Narwhals, new research


This video is called Narwhals | World’s Weirdest.

From the American Geophysical Union:

Mysterious lives of narwhals

February 9, 2018

Narwhals are some of the most elusive creatures in the ocean, spending most of their lives in deep water far from shore. But research being presented at the 2018 Ocean Sciences Meeting here on Monday may shed a bit of light on these enigmatic marine mammals.

New research shows narwhals may prefer to congregate near unique glacier fjords with thick ice fronts and low to moderate calving activity, where icebergs break off infrequently. It appears narwhals prefer the freshwater coming off still, serene glaciers over the silt-filled runoff discharged from very active glaciers.

The findings could help scientists understand a little more about the elusive narwhal and how these marine mammals might fare in a changing climate, according to the researchers.

“Arctic marine mammals are really good indicators of climate change because they are very specialized,” said Kristin Laidre, a scientist at the University of Washington in Seattle who will present the research Monday at the 2018 Ocean Sciences Meeting, co-sponsored by the Association for the Sciences of Limnology and Oceanography, The Oceanography Society and the American Geophysical Union. “They are finely attuned to specific environmental conditions, so they are good indicator species for how the physical changes many scientists are documenting in the Arctic can reverberate throughout the ecosystem.”

Scientists have known narwhals spend time at the fronts of glaciers in Greenland during the summer, which are hotspots for marine mammals, seabirds and fishes, but they did not know why narwhals have an affinity for these glaciers.

To better understand what glacier features narwhals prefer, Laidre and her colleagues used data from 15 narwhals outfitted with recorders that tracked each animal’s movements over four years in the 1990s and 2000s in Greenland’s Melville Bay, where narwhals congregate in summer. They combined this data with information about glaciers in Melville Bay over the same time period.

The researchers examined how narwhals behaved at the glaciers and collected information about each glacier’s physical properties to create models of narwhal behavior and tease out the animals’ preferences.

“Narwhals like slow-moving, big walls of ice where conditions are still and serene instead of a lot of runoff and disturbance,” Laidre said.

The researchers don’t know why the narwhals prefer these glaciers. They think the freshwater could shock small marine critters that are food for fish, which narwhals eat. Narwhals are also close relatives of beluga whales, which also seek out freshwater in summer to shed their skin, and it is possible there is something similar going on at the glacier front, Laidre said.

Laidre and her colleagues are performing additional research using a combination of moored instruments at glacier fronts, acoustic monitoring and land-based cameras to collect year-round data on narwhals to shed additional light on what physical properties of glacial fjords influence narwhal occurrence, relative abundance and acoustic behavior.

Laidre is also working on a project to use instrumented narwhals to examine the seafloor and measure ocean water temperatures. The research will help scientists better understand climate change in the high Arctic, Laidre said.

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Narwhal, dolphin news


This video says about itself:

Listen to a narwhal’s resting heartbeat | Science News

7 December 2017

Narwhals have a resting heart rate of about 60 beats per minute. Now researchers have observed narwhals’ heart rate dropping precipitously low when diving to escape from humans. As melting sea ice opens up the Arctic to more human activity, the mammals, known as “unicorns of the sea” for their single tusk, may be more exposed to the potentially harmful escape response, scientists say.

Narwhals react to certain dangers in a really strange way. ‘Unicorns of the sea’ fleeing humans show the physiological signs of also being frozen in fear. By Mariah Quintanilla, 2:41pm, December 7, 2017.

This video says about itself:

Science News – Whales & Dolphins Have “Human-Like” Societies

19 October 2017

AI eavesdrops on dolphins and discovers six unknown click types. Computer program picked out the noises from underwater recordings of 52 million echolocation signals. By Maria Temming, 2:00pm, December 7, 2017.

Sperm whale beached in Dutch Zeeland


This 1 December 2017 video is about the dead sperm whale beached in Domburg in the Netherlands.

Dutch regional broadcaster Omroep Zeeland reports today that a whale has stranded at Domburg beach.

It is a 13.5 meter long young male sperm whale. He was already dead when he beached.

Scientists will examine what caused his death. See here.

Bowhead whale behaviour, new study


This 22 November 2017 video is called Bowhead whales come to Cumberland Sound in Canadian Arctic to exfoliate.

From the University of British Columbia in Canada:

Bowhead whales come to Cumberland Sound in Nunavut to exfoliate

November 22, 2017

Aerial drone footage of bowhead whales in Canada’s Arctic has revealed that the large mammals molt and use rocks to rub off dead skin.

The footage provides one answer to the mystery of why whales return to Cumberland Sound, Nunavut, every summer, and helps explain some unusual behavior that has been noted historically by Inuit and commercial whalers living and working in the area.

“This was an incidental observation,” said Sarah Fortune, a PhD student at UBC’s Institute for the Oceans and Fisheries and lead author of a new study based on the findings. “We were there to document their prey and feeding behavior, but we noticed some strange behavior near the shore.”

Fortune and her colleagues — William Koski, a whale biologist with LGL Limited, and local Inuit hunters and fishers from Pangnirtung — watched from a boat as the whales turned on their sides and waved their flippers and tails in the air. It was clear the whales weren’t there just to feed.

When the researchers sent drones up to record the animals from above, they saw large boulders underwater and realized that the whales were rubbing against rocks to remove dead skin.

“We now know that Cumberland Sound serves as a habitat for feeding and molting,” said Fortune. “Very little is known about molting in any of the large whale species.”

The warmer coastal waters of summer might help facilitate molting, Fortune says. Ocean temperatures are expected to rise, and the change could have implications for the timing, duration and energy needed for molting, as well as the whales’ diets.

As oceans change, relatively large-bodied, fatty Arctic crustaceans known as zooplankton the preferred prey of bowhead whales could move to new habitats further north while smaller-bodied, temperate species that are lower in energy are likely to dominate the waters. Scientists don’t know how whales will adapt to the changing environment.

Fortune hopes to conduct further studies to determine whether bowhead whales molt primarily during summer months, and throughout their range.

Bowhead whales are the longest-living marine mammals on the planet, with lifespans up to 200 years.

Sperm whale tagged, video


This video, recorded near Dominica in the Caribbean, says about itself:

18 November 2017

Amazing Sperm Whale Cam – Blue Planet II Behind The Scenes

The team manage to tag a Sperm Whale with a small camera, allowing us to experience life under the waves.

Minke whale video from California, USA


This 26 October 2017 video from Captain Dave’s Dolphin and Whale Safari in Dana Point in California in the USA says about itself:

Stunning new video of a Minke Whale coming over and looking at us during yesterday’s whale watching trip! We see Minke Whales throughout the year and they can often be shy. Not this one! He “mugged” us, circling our boat over and over. Ocean conditions are gorgeous too. Look how calm the water is!