The recovery of the eastern Pacific gray whale population probably isn’t as successful as it was thought to be. Since the end of commercial whale hunting the population has risen to 20,000 whales.

When scientists observed some whales arriving at their breeding grounds malnourished they first thought this meant the population had risen to its pre-hunting numbers. The malnourishment serving as an indicator that the number of whales was as high as the ecosystem could sustain.

But new genetic research suggests that there were more whales pre-hunting than there are now. While malnourishment is still a sign that the ecosystem can’t support a larger population scientists now believe this is because climate change may be altering the whales’ food supply.

Of the three original grey whale populations, Atlantic, eastern Pacific and Western Pacific, only the eastern Pacific stock could be called numerous today. The Atlantic stock has been extinct for centuries while the western Pacific stock may down to as few as 120 animals.

Some hunting quotas exist for the easter Pacific gray whales, given to Russian and Native American tribes. The fact that the population isn’t as robust as previously thought may lead to lower quotas in future.

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