Warming Oceans are Stressing on Whales Already

Warming Oceans are Stressing on Whales Already



May 2007 - Climate change is making life 
more difficult for whales, dolphins and porpoises that must adapt to 
shrinking sea ice and decline in their prey species, according to a new 
study released by conservationists ahead of next week's annual meeting of 
the International Whaling Commission. 
Climate change impacts are greatest in the Arctic and the Antarctic, and 
the report finds cetaceans such as belugas, narwhals, and bowhead whales 
that rely on icy polar waters for habitat and food are likely to suffer 
most from the reduction in sea ice. 

Beluga whale in the St. Lawrence River surrounded by melting ice 
The cetaceans also must deal with changes in sea temperature and the 
freshening of seawater due to melting ice and increased rainfalls, finds 
the new report, "Whales in hot water?" published by the Whale and Dolphin 
Conservation Society and the global conservation organization WWF. 
"Whales, dolphins and porpoises have some capacity to adapt to their 
changing environment," said Mark Simmonds, international director of 
science at the Whale and Dolphin Conservation Society, WCDS. "But the 
climate is now changing at such a fast pace that it is unclear to what 
extent whales and dolphins will be able to adjust, and we believe many 
populations to be very vulnerable to predicted changes." 
Accelerating climate change adds to disturbances from other human 
activities, such as chemical and noise pollution, collisions with ships, 
and entanglement in fishing nets, which kills some 1,000 cetaceans every 
day, the conservation groups report. 
The Arctic could be seasonally free of sea ice as early as the year 2020, 
according to a report issued in April by the National Center for 
Atmospheric Research and the University of Colorado's National Snow and 
Ice Data Center. 
As sea ice shrinks, there will be more human activities, such as 
commercial shipping, oil, gas and mining exploration and development as 
well as military activities, in previously untouched areas of the Arctic, 
the conservation groups warn. 
"This will result in much greater risks from oil and chemical spills, 
worse acoustic disturbance and more collisions between whales and ships," 
said the report's lead author Wendy Elliott, from WWF’s Global Species 
Programme. 
Other projected impacts of climate change listed in the report include the 
reduction of available habitat for several cetacean species, such as river 
dolphins, that are unable to move into colder waters. 
Cetacean survival is also threatened by the acidification of the oceans as 
they absorb growing quantities of carbon dioxide, an increased 
susceptibility of whales, dolphins and porpoises to diseases, and reduced 
reproductive success, body condition and survival rates, the report finds. 

Minke whales surface in Antarctic sea ice 
Krill, a tiny shrimp-like marine animal that is dependent on sea ice, is 
the main source of food for many of the great whales, but the krill 
population is declining in key areas, the report finds. 
In the Antarctic, sea ice is decreasing in several areas, resulting in 
massive declines in krill which spend the winter under the ice. 
In January 2006, a 30 year study published by an international team of 
scientists showed that El Nino ocean warming events affect the 
availability of krill in the Southern Ocean. This in turn affects the 
number of calves produced by southern right whales in the South Atlantic, 
as ENS reported at the time. 
Southern right whales, Eubalaena australis, migrate from the South 
Atlantic to the Southern Ocean to feed. Following an El Niño event, 
changes in sea temperatures affect the availability of krill, which is the 
main diet of these whales. 
Keith Reid from British Antarctic Survey said in January 2006, "These 
results help us to understand processes in three connected oceans and are 
crucial to predicting the consequences of climate change on the whales." 
The conservation groups warn that the cumulative impact of climate change 
on other human induced impacts on cetaceans, such as pollution, bycatch 
and overfishing, means that reducing all threats to cetaceans is now 
essential for their long-term survival. 
The two conservation organizations are urging governments to cut global 
emissions of carbon dioxide by at least 50 percent by the middle of this 
century. 
They point to the latest report of the Intergovernmental Panel on Climate 
Change which showed may be possible to limit global warming if the world’s 
greenhouse gas emissions start to decline before 2015. 
The two organizations are calling on the International Whaling Commission, 
IWC, to facilitate research on future impacts of climate change on 
cetaceans, including by supporting a special climate change workshop in 
the coming year. 
They are urging the International Whaling Commission to detail cetacean 
conservation and management plans in view of the climate change threat, 
and in addition to increase efforts and resources to fight all the other 
threats to cetaceans. 
The Commission is already beginning to consider the impacts of the warming 
climate on whales, dolphins and porpoises. 
At an IWC Symposium on the State of the Conservation of Whales in the 21st 
Century that took place April 12 and 13 April at UN Headquarters in New 
York, delegates discussed whether the IWC is sufficiently robust to cover 
the full range of threats that whales face, such as climate change. 
While the 69 delegates from around the world, met specifically to explore 
policies for resolving the current impasse over commercial and scientific 
whaling at the International Whaling Commission, their discussion extended 
into options for dealing with the effects of climate change on cetacean 
survival. 
Symposium Chair Sir Geoffrey Palmer, former Prime Minister of New Zealand, 
was named New Zealand's representative to the International Whaling 
Commission in December 2002. 
"The scientists who spoke to this issue argued that although the RMP 
[Revised Management Procedure] model is simple, it was tested against a 
wide range of complexities, including ecosystem effects," wrote Symposium 
Chair Sir Geoffrey Palmer, former Prime Minister of New Zealand, president 
of the New Zealand Law Commission and commissioner to the IWC. 
"Other participants were less convinced and some argued that there are 
also moral and ethical considerations that should be taken into account," 
Palmer wrote in his summary of the Symposium's deliberations. 
The Palmer report as well as the conservationists' report "Whales in hot 
water?" will be available to the delegates from 75 IWC member nations when 
they convene on May 28 in Anchorage, Alaska.    

       
      

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