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Narwhals show 'alarming' response to stress
Melting sea ice has made the narwhal's natural habitat more accessible to humans.

Combination of low heart rate and hard exercise ‘costly’, researchers say 

Researchers that fitted heart monitors to narwhals have discovered how they respond to stress.

The study revealed that when narwhals are frightened, they swim hard to escape. But at the same time, their heart rate will also drop to just three or four beats per minute.

This combination of hard exercise and a low heart rate while not breathing underwater is costly, the researchers conclude. It could make it hard for the deep-diving whales to get enough oxygen to the brain.

The findings are published in the journal Science.

"How do you run away while holding your breath? These are deep-diving marine mammals, but we were not seeing normal dives during the escape period. I have to wonder how narwhals protect their brains and maintain oxygenation in this situation," said lead researcher professor Terrie Williams, from the University of California, Santa Cruz.

Known as the 'unicorns of the sea', narwhals reside in the Arctic ocean and have historically lived undisturbed by humans. In recent years, however, melting sea ice has made the area more accessible to shipping, oil exploration and other human activities.

In the study, researchers worked with native hunters to find narwhals trapped in nets. When the narwhals were released, the researchers deployed a submersible device to measure their heart rate.

The instruments had been used by the researchers in previous studies to assess the physiology and dive responses in bottlenose dolphins, Weddel seals, and other species.

"This was our first opportunity to put the tags on a deep-diving whale to monitor its physiological and behavioural response,” said Williams. "It all began with the work on dolphins in our facilities at Long Marine Laboratory."

Williams’ earlier studies revealed a surprising frequency of heart arrhythmias in dolphins and seals during intense exercise at depth. The new findings add to her concerns about the effects of disturbances that cause an escape response in deep-diving marine mammals.

"Unlike threats from predators like killer whales, noise from sonar or a seismic explosion is difficult to escape. Problems can start if the whales try to outrun it," she said. "The implications of this study are cautionary, showing that the biology of these animals makes them especially vulnerable to disturbance.”

She continues: “This technology has given us a window into the narwhal's world, and what we see is alarming. The question is, what are we as humans going to do about it?"

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Vets to run marathon for World Animal Protection

News Story 1
 Two recently graduated veterinary surgeons will be running the London Marathon in April to raise money for the charity World Animal Protection.

Alex Bartlett and Maeve O'Neill plan to run the race together if they are given the same start times.

Dr O'Neill said: "You're always limited in what you can do to help animals, so it is nice to raise money for a charity that helps animals around the world."

Dr Bartlett added: "I have never run a marathon before and am excited to run my first one for such a good cause!"

Both Dr Bartlett and Dr O'Neill have fundraising pages online. 

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News Shorts
BSAVA releases new Guide to Procedures

The British Small Animal Veterinary Association (BSAVA) has published a new edition of its Guide to Procedures for Small Animal Practice.

It has added four new procedures; cystostomy tube placement, endotracheal intubation, point-of-care ultrasound and wet-to-dry dressings.

BSAVA says that it is an essential step-by-step guide to diagnostic and therapeutic procedures performed in practice. The textbook includes new images and illustrations, as well as high-definition videos for use prior to procedures.

Nick Bexfield and Julia Riggs, editors of the new edition, said: "We have built upon the success of the previous editions by responding to the feedback received from the BSAVA readership, and hope this new guide helps to further increase the confidence and accuracy with which these procedures are performed."

Print copies are available in the BSAVA store, with a digital version in the BSAVA library.