Scientists have identified a section of warm ocean water in the northeast Pacific Ocean that they have called “the Blob”, which has been linked to the death an estimated one million seabirds.
According to CNN, this number of birds, called murres, died at sea in less than 12 months. It is considered one of the largest mass die-offs in recorded history.
A new study has linked this die-off to a warm “blob” in the ocean the size of Canada identified by scientists since 2013. It intensified in 2015 due to El Nino which ended in 2016. This water warmed by 3 to 6 degrees Celsius and because of a high-pressure ridge, was not disturbed by cool water.
The study linking these events explained that this happened for two reasons. First, the elevated temperatures reduce the quality and quantity of phytoplankton, reducing the fish fed on by the birds. The second is that salmon and Pacific cod, which compete with the birds for food sources needed to eat more. This has reduced the amount of food available for the murres, leading to starvation and death.
Some of the dead murres washed up on the shores of North America, but the researchers estimate that more died and stayed at sea.
This mass die-off also affected the birds ability to repopulate, especially since many which died were of breeding age.
Much like scientists have warned about rising ocean temperatures overall, from 1982 to 2015 the number of heat wave days on the ocean surface has seen an increase, with one study putting it as high as 82%.