NOEL KING, HOST:
Thirty-eight years ago, researchers from the New England Aquarium started studying North Atlantic right whales off the coast of eastern Maine. Large pods of the whales showed up like clockwork in late summer. Now those endangered whales come to that area only sporadically, and more and more, they're being seen far to the north. Murray Carpenter went out on a research vessel to learn more.
(SOUNDBITE OF WATER LAPPING)
MURRAY CARPENTER, BYLINE: It's just after dawn, and Amy Knowlton is surveying the waters of the Bay of Fundy, just off of easternmost Maine. She's a scientist with the New England Aquarium's Anderson Cabot Center for Ocean Life. She points out harbor porpoises chasing fish near the boat. And then something much larger appears in the windswept water.
AMY KNOWLTON: Whale behind us - it's probably a humpback or a fin whale. We'll get a better look.
CARPENTER: It turns out to be two humpbacks. One spouts near the boat.
(SOUNDBITE OF WHALE SPOUTING)
CARPENTER: It's a cool sighting, but these are not the whales she's after. Knowlton is hoping to find the North Atlantic right whales that she and her colleagues have been studying here since 1980. They're large baleen whales, with big heads and no dorsal fins. Researchers used to count as many as 200 foraging here in late summer. But they became scarce starting in 2010, and their range shifted dramatically.
Many more of the whales are now summering hundreds of miles north, in the Gulf of Saint Lawrence. Mariana Hagbloom, one of Knowlton's research assistants, surveyed that area in August and said it was nothing like the Bay of Fundy.
MARIANA HAGBLOOM: We had days where we were seeing about 50 individuals, working them from the boat and just right whales popping up left and right. It was a beautiful thing to see.
CARPENTER: But in total, fewer than 450 North Atlantic right whales remain, and their numbers have been falling for a decade as more have been entangled in fishing gear or killed by ships. Reproduction has also declined. Researchers found no new calves last winter. With the population on edge, scientists want to understand the reasons for the new migration pattern. Nick Record is with the Bigelow Laboratory for Ocean Sciences in East Boothbay, Maine.
NICK RECORD: My hypothesis is that this change in the migration patterns of whales is connected to their food resource, mainly Calanus. Calanus is like the battery of the Gulf of Maine.
CARPENTER: Calanus is a type of fat-rich plankton that's favored by many species. Record says the changing climate is not only rapidly warming the region's waters. It's also shifting the currents that once swept this important plankton into the deep basins where right whales feed, making it less available to them. Moira Brown, another scientist with the New England Aquarium team, says she actually finds hope in the habitat shift, all the way from the waters near Maine to the Gulf of Saint Lawrence.
MOIRA BROWN: It's not like it's right next door. Whales have to swim all the way around Nova Scotia. So what a tremendous response. You know, this is a highly endangered whale. There's not many of them left. And yet, they're demonstrating that they can respond to major changes in their habitat. And that's actually quite encouraging.
CARPENTER: But she says it's definitely slim pickings in the waters near Maine.
BROWN: It's not that this area's abandoned. But jeez, our count for this year is less than a dozen whales.
CARPENTER: Back at the dock, the crew ends their 30-mile survey, the last of the season, with no right whale sightings. But Amy Knowlton says it's worth sticking with the research.
KNOWLTON: We're in a whole new era right now with climate change, with habitat shifts. It's important with this long-term study to sort of maintain some of the basic efforts that we've had so that we can better understand what's happening for the whales.
CARPENTER: She says they'll be back in the Bay of Fundy next summer, gathering more data, even if the right whales are few and far between. For NPR News, I'm Murray Carpenter.
(SOUNDBITE OF SEAS OF YEARS' "IN COLLUSION WITH THE WAVES")
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