The ‘Blob,’ a massive marine heat wave, led to an unprecedented seabird die-off
From 2015–2016, 62,000 dead common murres washed onto U.S. and Canadian Pacific coast beaches
New research links a massive die-off of these seabirds, called common murres, with a powerful marine heat wave in the Pacific Ocean that lasted two years.
Common murres are arguably the most
successful seabirds in the Northern Hemisphere. The penguinlike seafarers can
crisscross vast expanses of ocean faster than any other northern seabird, and can
dive the length of two American football fields to snatch small fish.
But from 2015 to 2016, this
superstar bird experienced an unprecedented die-off.
Over that period, about 62,000
emaciated, dead or dying murres (Uria
aalge) washed onto beaches from Southern California to the Aleutian Islands
of Alaska, a new study finds. What’s more, colonies throughout this range
failed to reproduce during and shortly after the same time. All together, an
estimated 10 to 20
percent of the region’s total population was wiped out,
researchers report January 15 in PLOS ONE.
The cause? A gargantuan, extended
marine heat wave nicknamed the Blob whose impact reverberated throughout the
food web, the scientists say. Warmer ocean temperatures shifted the range and
makeup of plankton communities and amped up the metabolic demands of all fish, shrinking
one of the ecosystem’s key food supplies and starving out murres.