Whale woe in the Atlantic
Source: Daniel Cressey, Nature
Human activity is still killing right whales, one of the most endangered animals in the ocean. An analysis of four decades of whale deaths shows that attempts to prevent them have not had a demonstrable impact.
Only around 460 North Atlantic right whales (Eubalaena glacialis) are thought to be swimming the waters off the eastern seaboard of Canada and the United States. The governments of both countries have implemented several measures to protect whales from becoming entangled in fishing gear or being hit by ships, such as the US ‘ship strike rule’ that limits vessel speeds in certain areas. That rule came into force in 2008 and is due to expire next year.
Marine-mammal researchers Julie van der Hoop and Michael Moore, both at the Woods Hole Oceanographic Institution in Woods Hole, Massachusetts, and their colleagues, analysed all known deaths of eight species of large whale in the northwest Atlantic between 1970 and 2009. During that time 122 right whales died, along with 473 humpbacks (Megaptera novaeangliae), 257 fin whales (Balaenoptera physalus) and scores of whales of other species. When the authors were able to assign a cause of death, ‘human interactions’ was the most common, appearing in 67% of cases. Entanglement in fishing gear was the main cause of death in this category.
The protection measures seem to have had no impact on whale deaths, according to the study published online in Conservation Biology1. Although several of the rules were implemented only towards the end of the study period, Moore still admits that the finding is “hugely disappointing”.
But Moore also notes that the study was a very “broad brush” analysis. There are specific local efforts — such as moving shipping lanes in the Bay of Fundy between the Canadian provinces of New Brunswick and Nova Scotia — that “undoubtedly” helped the conservation of right whales, but which would not show up in a wider view.
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