Southern California marine mammal enthusiasts should note that a special whale named Varvara will be passing through local waters today and Friday.
The 8-year-old female gray whale, sporting a satellite tag that reveals her position, is special because she has swum all the way from Sakhalin Island in the western North Pacific off Russia, providing scientists with more evidence that Western Pacific gray whales may not be as distinct from Eastern Pacific gray whales as previously believed.
Varvara hails from a critically endangered population of perhaps 130 Western Pacific gray whales, with very few breeding-age females. There are about 20,000 Eastern Pacific gray whales, famous for their annual 10,000-mile round-trip migration from the Bering and Beaufort seas to and from winter breeding areas in lagoons along the Baja California coastline.
It has become increasingly evident that both populations utilize the same breeding areas. However, David Weller, a marine mammal specialist with the National Marine Fisheries Service, has authored a manuscript (under peer-review) which states that despite this mixing, "Significant DNA and nuclear genetic differences between whales utilizing the Sakhalin feeding ground and those summering in the Eastern North Pacific support the continued recognition of Sakhalin animals as a distinct genetic unit."
Varvara is expected to pass through the Los Angeles/Long Beach area late today and pass Orange County and San Diego on Friday.
Her position is relayed to scientists at Oregon State University's Marine Mammal Institute. (People can obtain weekly updates of Varvara's progress, each Monday, via this link.)
Her odyssey follows that of Flex, who was fitted with a satellite tag a year earlier. Flex, a male Western Pacific gray whale, surprised scientists when he crossed from the western Pacific to this side, and joined with Eastern Pacific grays during their migration.
The tag worn by Flex, however, stopped transmitting off southern Oregon. Varvara's tag is still relaying her position. She has been photographed with other gray whales off Oregon and Northern California, but it was not clear whether they were Western Pacific or Eastern Pacific grays.
It might seem to some that, given this information, there may be only one gray whale population in the North Pacific, and it just so happens that some gray whales utilize Russian coastal waters during the summer.
But Weller says there have been observations of gray whales off Japan and China in the winter and spring, and a photo-ID match showing a Honshu-Sakhalin link, suggesting that "not all gray whales identified off Sakhalin share a common wintering ground."
Thus, a strong conservation efforts is still required in order to protect the small Western Pacific gray whale population.
Varvara will be nearly impossible to discern from other southbound gray whales. It's not known if she will pass beyond or inside of the Channel Islands. If boaters spot a very small tag just in front of the first dorsal knuckle on a whale's back, however, they could be seeing Varvara.
As of the time of this post, Bruce Mate, who runs the Marine Mammal Institute, could not be reached for comment. He may have been too busy trying to physically locate Varvara.
-- Pete Thomas
Note: This research was conducted by A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS) and Oregon State University Marine Mammal Institute in collaboration with the U.S. National Marine Fisheries Service, Kronotsky State Nature Biosphere Reserve and the Kamchatka Branch of the Pacific Institute of Geography. The research was contracted through the International Whaling Commission (IWC) and International Union for Conservation of Nature (IUCN) with funding from Exxon Neftegas Ltd. and Sakhalin Energy Investment Company Ltd.