Sharp Decline in Birth Rates for Endangered Right Whales Has Scientists Troubled

Feb 17, 2017

A sharp drop in the birth rate of rare North Atlantic right whales has scientists worried. So far this year, only three calves have been identified. A more typical season might bring between ten and fifteen newborn calves.  

"It's a frighteningly low number," says Dr. Charles "Stormy" Mayo, a Senior Scientist at the Center for Coastal Studies in Provincetown. 

Estimates of the existing population of these whales, Mayo says, puts them at just over 500 individuals remaining.  

This is the time of year for the rare right whales to appear in Cape Cod Bay, returning from more southern waters. A sighting earlier this week of 19 whales feeding together was a bright spot for researchers. But the low birth number, coupled with the documentation of at least four right whale deaths in the previous year, Mayo says, is very troubling.

No single cause has been identified for the dramatic decline in calves this year. Possible contributing factors include diminishment in food supply, increased pollution along the East Coast, and perhaps a genetic bottleneck. Climate change may also be an influence.  

There remains a possibility that more calves will be sighted later in the season, especially if, as some scientists are suggesting, the whales are changing their calving grounds.  If that is the case, Mayo says, researchers will be looking for these nursing calves to appear in Cape Cod Bay late in April.

Meanwhile, he says, right whales recently have been aggregating along Truro and Wellfleet, visible from the shore - so keep an eye out.

The full conversation is posted in the audio above - give it a listen.