The ‘Blob,’ a massive marine heat wave, led to an unprecedented seabird die-off
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...