February 24, 2020 — The following was released by NOAA Fisheries:
Whales undertake some of the longest migrations on earth, often swimming many thousands of miles, over many months, to breed in the tropics. The question is why—is it to find food, or to give birth?
In a research paper in Marine Mammal Science, scientists propose that whales that forage in polar waters migrate to low latitudes to maintain healthy skin.
“I think people have not given skin molt due consideration when it comes to whales, but it is an important physiological need that could be met by migrating to warmer waters,” said Robert Pitman, lead author of the new paper and marine ecologist with Oregon State University’s Marine Mammal Institute. He was formerly with NOAA Fisheries’ Southwest Fisheries Science Center in La Jolla, California.
More than a century ago, whalers recognized that most whales that forage in high latitudes migrate to the tropics for calving. Scientists have never agreed on why. Because of their size, large whales should be able to successfully give birth in frigid polar waters. Due to reduced feeding opportunities in the tropics, most whales fast during their months-long migrations.
So why go to the trouble?