Researchers recently spotted a bowhead whale, typically found in Arctic waters, quite far from home in Cape Cod Bay, Mass.
Moreover, the bowhead was found feeding among a large group of right whales in the embayment.
Bowheads are related to right whales, and like the right whale, bowheads are slow-moving filter feeders that subsist largely on zooplankton such as the copepods that are abundant in Cape Cod Bay at this time of year, the researchers said.
But it is unlikely that the bowhead had ever had a taste of copepods before traveling so far south.
The rare sighting of a bowhead whale so far afield could mean that conditions in its home waters have forced it to look for food elsewhere.
Charles "Stormy" Mayo, director of the right whale research program at the Provincetown Center for Coastal Studies (CCS), told Nature World News that over the decades he has been studying marine life in Cape Cod Bay, he's seen a huge increase in the number of right whales come into the bay.
Now, within the past two years, bowhead whales are showing up, he said. This is the second time on record that a bowhead whale has been seen so far south in the North Atlantic.
There are only about 500 right whales thought to be alive today, Mayo said, noting that they are the rarest mammal on Earth.
"Each year we've been seeing about half of the population of right whales coming into this embayment," Mayo said Friday from a boat in Cape Cod Bay surrounded by right whales.
"And now we've got a bowhead," he said.
The bowhead was spotted feeding among a group of right whales April 11.
"We're seeing animals responding to a changing ecosystem," Mayo said. When asked whether the bowhead could have been forced south because of a change in its access to food farther north, Mayo said it was not easy to attach a reason for the occurrence.
"We're talking about the biology of complicated creatures," he said, adding that their presence in Cape Cod is, at the very least, an indication of a change in the ecosystem.
Bowheads and right whales alike are protected under the Endangered Species Act and the Marine Mammal Protection Act. The animals are vulnerable to ship strikes and Mayo and his research team have a special federal permit that allows them to boat in the water near the whales.
"This is yet another remarkable sighting in what has been a remarkable several years in our studies of Cape Cod Bay," Mayo said in a statement released Friday. "Two years ago we saw our first bowhead, an animal that should be 1,000 miles from Cape Cod, then last year we saw the first calving of a right whale in Cape Cod waters, and now we have a bowhead again here, this time feeding with right whales. These observations along with extraordinary number of rare right whales in Cape Cod Bay seem to be pointing to profound changes in the coastal habitat, to which the whales are responding."
Bowhead whales are one of the heaviest whales on Earth, reaching up to 100 tons, second only to blue whales. There are, however, several species of whale that grow longer than bowhead whales, such as fin whales.