Cookie use on MRCVSonline
We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive all cookies.
If you would like to forward this story on to a friend, simply fill in the form below and click send.

Your friend's email:
Your email:
Your name:
Send Cancel

Climate change could be affecting beluga whales’ ability to dive, study finds
“The relationship between physical condition and oxygen storage capacity may be a vicious cycle in beluga whales."
Scientists investigate the health and condition of northern beluga whales

The physical condition of beluga whales affects their capacity to store oxygen in blood and muscle tissue, and therefore could impact their ability to dive, a new study has concluded.

In the study, an international team of scientists explored the relationship between body condition and oxygen storage in 77 beluga whales in the eastern Beaufort Sea.

They found that concentrations of muscle myoglobin and blood haemoglobin are 12 and 27 per cent higher, respectively, in beluga whales in peak physical condition, compared to those of lower condition.

Scientists estimate that these differences are equal to at least a three-minute reduction in maximum dive time of the whales with the lowest body condition. The findings are published in the Journal of Experimental Biology.

The international study started in response to a 2014 report into the growth rates of Beaufort sea beluga whales. The report concluded that the beluga whale growth rate had declined over the past 20 years as a result of climate change.  

Because diving depth in toothed whales is linked to body size, the researchers set out to see if the smaller size could affect their ability to dive. However, they found that body condition and not body mass was the most important factor predicting blood and muscle oxygen storage capacity.

Previous research suggested that the northward migration of less energy-dense prey species was the driving force behind the fall in body condition.

“Considering that the peak biomass of Arctic cod, the beluga’s main prey, is found between depths of 350 to 500 metres, and that the largest and most energy-rich cod are found at the deepest depths, declines in body condition may affect the ability of the whales to reach their preferred prey,” explained lead author of the study Dr. Emily Choy, a researcher at McGill University, Canada.

Dr Michael Berenbrink from the University of Liverpool’s Institute of Integrative Biology added: “The relationship between physical condition and oxygen storage capacity may be a vicious cycle in beluga whales, in which environmental changes resulting in decreased condition of the whales, affects their ability to forage, leading to further reductions in their condition through the diminished consumption of their prey.”

University of Manitoba biologist D. Kevin Cambell said: “Equally concerning is that results from our study suggest environmental changes affecting the physical condition of beluga whales may also affect their ability to evade predators and sea ice entrapments, thus leading to increased mortality risks.”

Become a member or log in to add this story to your CPD history

Pair of endangered Amur leopard cubs born at Colchester Zoo

News Story 1
 Keepers at Colchester Zoo are hailing the arrival of a pair of critically endangered Amur leopard cubs.

The cubs were born to first-time parents Esra and Crispin on the 9 September. This is the first time the Zoo has bred Amur leopard cubs on-site.

Amur leopards originate from the Russian Far East and north-east China. In the wild they are threatened by climate change, habitat loss, deforestation and the illegal wildlife trade.

The cubs are said to be “looking well” and are expected to emerge from their den in a few weeks.  

Click here for more...
News Shorts
BEVA survey seeks views about antibiotic use in horses

Equine vets are being invited to participate in a BEVA survey that aims to find out more about antimicrobial resistance in equine veterinary practice.

Designed by researchers at the University of Liverpool and incoming BEVA president Tim Mair, the survey aims to fill gaps in knowledge about how antimicrobials are being used in equine practice and the landscape of resistant infections encountered in equine practice.

Researchers hope the results will lead to a greater understanding of the role of antimicrobial treatment and antimicrobial resistance in horses and protect antibiotics for the future of equine and human health.