These waterfowl are declining in New Brunswick, Nova Scotia and the Mainebut more numerous than before in Newfoundland.
By tagging and following these migrating ducks, the scientists hope to be able to explain this situation which has intrigued them for more than a decade, and for which certain hypotheses have been put forward.
The most common hypothesis to explain the decline of eiders in certain regions is the scarcity of their main food source: the blue mussel (Mytilus edulis).
They feed on those found in the Gulf of Maine, one of the fastest warming bodies of water on the planet. Blue mussels only survive under very specific conditions. They therefore suffer from this change in temperature and cannot survive in water that is too hot.
Dustin Meatteythe director of waterfowl programs at the Biodiversity Research Institute, in the Mainealso evokes the proliferation of the green crab (Carcinus maenas).
This invasive species attacks mussels in particular, which eiders are fond of.
Mark Mallorythe director of coastal wetland ecosystems research at the University Acadiain Nova Scotia, indicates that the majority of researchers agree that the maritime environment must be looked at to explain the decline of eiders, a species he has studied for more than twenty years.
Canadians and Americans collaborate on the project. The Canadian Wildlife Service, Environment and Climate Change Canada, the University Acadiathe U.S. Marine and Wildlife Service (United States Fish and Wildlife Service) and the Fisheries and Wildlife Department of Maine are partners.
Research has been done on the subject before, but never on such a large scale, according to Dustin Meattey.
The researchers began their work last year in the Maine and in Quebec, where they attached tracking devices to eiders. They are continuing in the same vein this spring in New Brunswick and Nova Scotia.
They plan to head for Newfoundland and Labrador soon after, unless the breeding season there is delayed due to snow. If that is the case, Dustin Meattey indicates that the researchers will go there next year.
Their operations will target breeding eiders.
According to the teacher Mark Malloryof the University Acadiaboth Canadian and American authorities are interested in eiders, in particular because their down is of commercial interest and they are hunted on both sides of the border for their plumage.
Whenever humans hunt a species, and you want to do it in a sustainable way, you have to know if the amount you’re taking from a population is sustainable.he said.
Both countries are also signatories to the Migratory Birds Convention, an agreement for monitoring and conservation.
Mark Mallory emphasizes that what is happening with the species should be seen as a symptom of the health of the environment on the Atlantic coast. Variations in eider populations can tell a lot about the state of marine and coastal ecosystems, he notes.
According to the teacher Malloryresearchers have already begun to receive interesting data from eiders in which tracking devices were implanted last year in Quebec and the Maine.
Data for those in the Maritime provinces should be added in the coming year. After three or four years, he says, that data begins to show trends that can be trusted.
According to the report of Raechel Huizinga, CBC