The deaths of some 700 sooty shearwaters (Puffinus griseus) along the cost of Cobquecura, 434 kilometers south of the Chilean capital, has prompted the authorities to open a legal investigation. So far there are two hypotheses: the birds drowned after becoming entangled in fishing nets, or they ingested a toxic substance.

“It isn't an isolated case,” Pedro Arrey, regional director of the non-governmental National Committee for the Defense of Flora and Fauna, told Tierramérica.

Last year, thousands of shearwaters and penguins died in other coastal areas, said Arrey, who is waiting for the results of the investigation before blaming a paper pulp mill that discharges its wastewater 10 kilometers from the site.

“We are hoping to clear up what has occurred in the last few years,” he said.

On Feb. 27, much of the Chilean coast was hit by a massive earthquake and subsequent tsunami.