Whale populations back before commercial whaling began in the 17th and 18th centuries have been wildly underestimated.
In fact, the authors report today in the journal Science, their analysis showed that the pre-whaling, or “historic,” population of humpback whales in the North Atlantic was 240,000, 12 times as many as the current historical-statistical estimate of 20,000. There are about 10,000 now.
Roman and Palumbi also estimated the historic population of fin whales at 360,000, nine times more than historical-statistical estimates of 40,000, and the population of minke whales at 265,000, as against statistical estimates of approximately 100,000.
The findings could play an important role in decisions of the International Whaling Commission, the 51-nation convention that imposed an international moratorium on whaling in 1985 to allow stocks to rebuild after the decimation of the 19th and 20th centuries.
The commission has agreed that whaling should not be allowed until stocks reach at least 54 percent of historic levels. Under this stipulation, the current North Atlantic humpback population is about 50 percent of historical-statistical estimates, while fins, at 56,000 and minkes at 149,000 have already exceeded the threshold.
But under the new genetics-based estimates, only the minkes are close to 54 percent. “One of the things that the data tell us is that we have a long way to go for recovery,” Roman said in a telephone interview. “Things were vastly different in the relatively recent past. How do we get to that restoration? I don’t know.”