Almost 400 endangered sea turtles were found dead off the coast of El Salvador, the country’s Ministry of Environment and Natural Resources department reported on November 3.

Crew sailed to the Bay of Jiquilisco in Usulutan and La Puntilla Beach in La Paz, where they collected samples of water and tissue samples from the dead turtles. The reptiles were identified as chelonian turtles, which are listed as endangered by the International Union for Conservation of Nature.

Environmentalists reported that the high chlorophyll levels along the coast, as observed from NASA satellite images, may have caused toxic algae blooms that killed the turtles. Credit: Facebook/Ministry of Environment and Natural Resources (Ministerio de Medio Ambiente y Recursos Naturales via Storyful)