A three-year ocean heat wave known as ‘the Blob’ appears to have caused a decline in the humpback whale population.
A new study published in Royal Society’s Open Science journal shows the whales’ population declined by 34% from 2013 to 2021. Researchers say the 2014-2016 marine heat wave, the strongest recorded globally, appears to have altered the course of the whales’ recovery. The ‘Blob,’ which wreaked havoc on BC’s coastline in 2015-2016 after passing south from Alaska, has been linked to a decline in plankton and feeder fish populations, important food sources for whales and their food chain.
Humpback whales have been slowly recovering since commercial whaling ended in 1976. By 2012, their population had recovered to nearly 34,000 animals.
However, the study found after just nine years from 2012-2021, the population had declined by 7,000 individuals.
Humpbacks spend winters in warmer waters in Mexico and Hawaii, and migrate to BC and Alaska every summer to feed. Researchers believe the ‘Blob’ and its impacts on feeding patterns in BC and Alaska are the main culprits for the decline.
