Copepod Presence Key to Right Whale Movements

Photo courtesy of NOAA

Scientists have established firm links between the warming of deep waters in the Gulf of Maine and the reduction of food for the North Atlantic right whale, the world’s second-most endangered marine mammal. The researchers, led by Nick Record of the Bigelow Laboratory for Ocean Sciences in Boothbay, showed the warmer water in the eastern Gulf has sharply reduced the numbers of the whales’ favorite prey, the copepod Calanus finmarchicus, a tiny flea-like creature they scoop up by the millions with their sieve-like baleen. In Cape Cod Bay and the western Gulf of Maine — where right whales still come in large numbers in the spring — copepod numbers have remained strong. But in the eastern Gulf, where copepods are more dependent on seasonal hibernation, the data showed steep declines and deepwater warming much more severe than Record had expected.