What's Wrong With Southern Right Whales? 100s Washed Up Dead in Patagonia Over Past Five Years

The payoff straight away: No one quite knows why 308 southern right whales, 88% of them less than three months old and many of them with unusually thin layers of blubber, have washed up dead on the shores of Patagonia since 2005. What we do know is that it's one of the largest die-offs of great whales ever recorded.

Occurring along Peninsula Valdés in Argentina--one of the most important calving and nursing grounds for the species, according to Dr Howard Rosenbaum of the Wildlife Conservation Society--potential explanations for the die-off include: Biotoxins, disease, environmental factors at their nursing grounds, and variations in prey availability in their feeding grounds.Raising a call to research, Dr Marcela Uhart, also of WCS, said,

We need to critically examine possible causes for this increase in calf mortality so we can begin to explore possible solutions. Finding the cause may require an expansion of monitoring activities to include the vast feeding groups for the species.

How vast? Try entirely around Antarctica.

Southern Right Whales Endangered, But Populations Increasing
Though still listed as endangered by the IUCN, with an estimated population over about 12,000 worldwide, the southern right whale is generally considered a conservation success story. Populations have rebounded since hunting of them was prohibited in 1937, growing about 7% per year since the 1970s. Northern right whale populations have not fared so well, with populations remaining low.

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photo: Michele Molinari/Globevisions

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Tags: Argentina | Endangered Species | Whales

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