A study revealed that 4 million common murres died during the North Pacific marine heatwave known as the 'Blob,' marking the biggest bird die-off in recorded history.

New research shows the marine heat wave that spread from California to Alaska starting in 2014 caused common murres to starve to death.

The murre die-off might have gone unexplained if it weren't for decades of observations from researchers and citizen scientists.

Kodiak Island residents have been reporting a large number of common murres washing up dead on local beaches.

While reproductive failure is common for some species like black-legged kittiwakes, it isn’t for murres. In some places less than one percent of the chicks survived.