ALBUFEIRA

A cada ano que passa com as temperaturas médias globais em contínua (cada vez parecendo mais irreversível) subida, recordando como mais um exemplo (pelo feito desde 2016, aparentemente tardio) do ocorrido entre o Verão de 2015 e a Primavera de 2016: afetando as condições ambientais das aves marinhas do norte do Oceano Pacífico − aqui os ARAUS ( ou guillemots) − e vitimando mortalmente um milhão delas.

Worst marine heatwave on record

killed one million seabirds

in North Pacific Ocean

(January 15, 2020 7.07pm GMT/theconversation.com)

Colónia de Araus

The common guillemot (known as the common murre in North America) breeds in both the Pacific and the Atlantic and is among the most abundant seabirds in the northern hemisphere. But like many other seabirds, its numbers have declined over the last few decades. Part of that decline is due to the marine environment – a seabird’s home and hunting ground – becoming increasingly unpredictable and difficult to survive in.

Between the summer of 2015 and the spring of 2016, a marine heatwave swept the northern Pacific Ocean that was hotter and lasted longer than any since records began in 1870. Known as “the blob”, the heatwave caused sea surface temperatures along the Pacific coast of North America to rise by 1-2°C. That may sound trivial, but it was enough to cause massive disruption in the marine ecosystem. The fish that common guillemots normally eat, such as herring, sardine and anchovy, either died or moved into cooler waters elsewhere, leaving the guillemots with little to eat. As a result, many birds starved.

On January 1 and 2 2016, 6,540 common guillemot carcasses were found washed ashore near Whitter, Alaska. David B. Irons, CC BY

A new study has revealed that one million common guillemots died due to the heatwave, and two thirds of them are thought to have been breeding adults. In a healthy population, about 95% of the breeding birds survive from one year to the next. But a bad year for adult survival causes big problems for the total population.

[continua]

(theconversation.com/worst-marine-heatwave-on-record-killed-one-million-seabirds-in-north-pacific-ocean-129842)

(imagem: Duncan Wright/Wikipedia, CC BY-SA)