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Rare species of North Pacific right whale carries a tune across the

first_imgCrance says the songs recorded are in many ways similar to the common gunshot calls. Federal researchers in the Bering Sea have released recordings of songs by some of the rarest whales in the world. While this is exciting news for marine science, it could point to heartache for North Pacific right whales. This isn’t to say North Pacific right whales don’t make sounds. “We know that they are in the southeastern Bering Sea in the summer,” she said, “but where do they go when they leave or if they leave the Bering Sea is still unknown.” First, it’s important to understand that North Pacific right whales are critically endangered. The name “right” whale is a vestige from the commercial whaling era,  when they were considered the “right” species to hunt. Slow moving and buoyant, right whales remained afloat after being killed. That’s the working theory for now and the one put forward this month in an article published in the Journal of the Acoustical Society of America. They were nearly wiped out in the early 20th century. “It’s difficult for us to know for certain why they’re singing,” Crance said. “But our best guess and our current hypothesis is that it appears to be some kind of a reproductive display.” “This behavior has not been documented yet in any of the other right whale species or populations,” said Jessica Crance, a NOAA marine biologist at the Alaska Fisheries Science Center’s Marine Mammal Laboratory in Seattle. In 2009, researchers in the Bering Sea first noticed these sounds during summer surveys. Long-term data from acoustic recorders over eight years showed evidence of right whale songs — something heretofore unknown for the species. “But they’re producing it in a very regular rhythmically pattern consistent manner. So the same number of gunshots, the same timing in between, and those patterns are repeated over and over for hours,” she said.center_img But Crance told CoastAlaska there’s so much about these whales that’s not understood. Now, with an eastern population of just 30 animals — they could be lonely. All of the confirmed recordings were from males possibly seeking female companionship. NOAA Fisheries marine biologist Jessica Crance deploys a sonobuoy in the northern Gulf of Alaska in 2015 to acoustically monitor for North Pacific right whale calls. (Photo by Brenda Rone/NOAA Fisheries) So what does it all mean? For the first time, researchers have recorded and studied songs from North Pacific right whales. So far it seems limited to the Bering Sea. “Within our population the most common call type is what’s called the gunshot sound,” she said. Even their migration routes and their breeding grounds remain a mystery. An eastern North Pacific right whale, the world’s most endangered great whale, spotted in the southeastern Bering Sea in 2004. (Photo by John Durban/NOAA Fisheries) Hunting right whales in Alaska has been banned since 1949. But contemporary threats persist — mostly vessel strikes and entanglement in fishing gear.last_img read more

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