Mi­grat­ing whale ‘Var­vara’ sets long-dis­tance record

The China Post - - ARTS -

A lone fe­male West­ern North Pa­cific grey whale has set a record for long-dis­tance migration, ac­cord­ing to a study Tues­day.

Nick­named Var­vara, the nineyear-old whale was tagged off Rus­sia’s Sakhalin Is­land in 2011.

She crossed from the north­west­ern to the north­east­ern side of the Pa­cific and fol­lowed the west­ern Canadian and US coast down to breed­ing grounds off Baja Cal­i­for­nia, Mex­ico.

She swam 10,880 kilo­me­ters (6,800 miles) in 69 days — “the long­est recorded dis­tance trav­eled dur­ing a mam­mal migration,” the sci­en­tists said.

She then re­turned home by a slightly more southerly route, com- plet­ing a 172-day, 22,511-kilo­me­ter (14,069-mile) trek, also a record for round-trip migration.

Un­til now, the ac­knowl­edged record-holder for mam­mal migration has been the hump­back whale, one of which made a one-way trip of 9,800 kilo­me­ters from wa­ters off Brazil to Mada­gas­car, ac­cord­ing to a 2010 study.

The new re­search, pub­lished in the Bri­tish jour­nal Bi­ol­ogy Let­ters, raises in­trigu­ing ques­tions about grey whales — Latin name Eschrichtius ro­bus­tus.

Grey whales ex­ist in both the eastern and west­ern North Pa­cific and con­ser­va­tion­ists con­sider the two pop­u­la­tions to be sep­a­rate.

Com­mer­cial whal­ing rav­aged num­bers on both sides of the ocean.

How­ever, those in the east have largely re­cov­ered while those in the west are tee­ter­ing on the edge of ex­tinc­tion — and in­deed at one point were thought to have been wiped out.

The In­ter­na­tional Union for Con­ser­va­tion of Na­ture (IUCN) lists the west­ern grey whale pop­u­la­tion at around 130, mak­ing it “crit­i­cally en­dan­gered.”

But if Var­vara’s trek is any guide, there could be a ge­netic mix be­tween the eastern and west­ern pop­u­la­tions, the in­ves­ti­ga­tors said.

In other words, some pre­sumed west­ern grey whales could ac­tu­ally be eastern grey whales.

“The pop­u­la­tion iden­tity of whales off Sakhalin Is­land needs fur­ther eval­u­a­tion,” said the scien- tists, led by Ladd Irvine at Ore­gon State Uni­ver­sity.

Six other whales were also given satel­lite-mon­i­tored tags.

Along with Var­vara, two oth­ers also crossed into re­gions in­hab­ited by non-en­dan­gered eastern grey whales.

They were “Flex,” a 13-year-old male that crossed to wa­ters off Ore­gon, a jour­ney of 7,611 kilo­me­ters, and “Agent,” a six-year-old fe­male, which headed to the Gulf of Alaska, 5,464 kilo­me­ters away.

The migration pat­terns break with the idea that grey whales fol­low ex­clu­sively north-south mi­gra­tory routes along coasts and demon­strate that th­ese mam­mals have “nav­i­ga­tional skills across open wa­ter,” the pa­per said.

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