A humpback whale. Photo by Brett Atkins/Shutterstock
NEW YORK, Dec. 4 (UPI) -- If you've been wondering where the most the most genetically distinct group of humpback whales in the world are, don't fret, scientists have been asking themselves the same question. And now they have an answer -- the Arabian Sea, the northern tip of the Indian Ocean wedged between India, Africa and the Middle East.
Humpback whale populations there have remained almost entirely isolated for 70,000 years -- a remarkable phenomenon considering the marine mammals are famous for long-distance migrations. Researchers have previously measured the journeys of humpback whales, traveling between polar feeding regions and tropical breeding spots, at more than 5,500 miles.
"The epic seasonal migrations of humpbacks elsewhere are well known, so this small, non-migratory population presents a wonderful and intriguing enigma," Tim Collins, a researcher with the Wildlife Conservation Society, explained in a recent press release. "They also beg many questions: how and why did the population originate, how does it persist, and how do their behaviors differ from other humpback whales?"
Collins and a team of scientists were able to measure the genetic distinctiveness of Arabian Sea humpback whales after collecting and testing nuclear and mitochondrial DNA extracted from 47 different whales.
In their new study on the humpbacks, published this week in the journal PLOS ONE, researchers suggest the population's uniqueness may have been established by glacial episodes during the late Pleistocene Epoch, as well as changes in the patterns of the Indian Monsoon.
Over time, their uniqueness was likely preserved an accentuated by breeding cycles that are asynchronous with other humpback populations. While the findings are remarkable and exciting, they add a new sense of urgency to humpback conservation efforts.
"The Arabian Sea humpback whales are the world's most isolated population of this species and definitely the most endangered," explained Howard Rosenbaum, the director of WCS's Ocean Giants Program. "The known and growing risks to this unique population include ship strikes and fishing net entanglement, threats that could be devastating for this diminished population."