Scientists with the Department of Fisheries and Oceans (DFO) say they’ve been unable to determine an obvious cause of death for a grey whale that was found Tuesday night in Boundary Bay.
The mature, 14-metre adult female was the sixth grey whale to turn up dead in B.C. this year, and one of nearly 150 to die between Mexico and Alaska in the last six months, according to the U.S. National Oceanic and Atmospheric Administration (NOAA).
Earlier in May, two grey whales had to be rescued after becoming stranded in Boundary Bay.
DFO marine mammal coordinator Paul Cottrell said officials conducted a necropsy of the whale on Thursday, but found “no conclusive cause of death.”
Cotrell added that the whale had a thicker fat layer than others the DFO had recently examined.
He said tissue samples from the necropsy are now being sent to labs in the U.S. and Canada for analysis, a process that could take weeks or months.
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As for the mystery of the pacific coast whale die-off, Cotrell said the DFO continues to work with partners in Mexico and the NOAA.
He said there are a number of theories as to what is causing the deaths, including concern about a lack of food leading to the whales having compromised body conditions for their annual northward migration.
There are an estimated 27,000 grey whales in the eastern north Pacific Ocean, according to the NOAA. The animals winter in Mexico where they feed and breed before migrating to Alaska where they build fat over the summer.