Dead dolphins are an increasingly common sight on beaches across Northern Peru, with more than 200 carcasses found last week alone. The cause is still a mystery.
Last month's total of 400 dead dolphins, according to officials, is nearly half the number
discovered during the entire year of 2012, the Associated Press reported.
Authorities have yet to establish a cause for the dolphin deaths and are conducting necropsies on the most recently recovered dolphin carcasses focusing on the mammal's lungs, kidneys, and livers in an attempt to understand what triggered the apparent die-off.
Urgent: Do You Approve Or Disapprove of President Obama's Job Performance? Vote Now in Urgent Poll
According to Jaime de la Cruz, a technician with Peru's IMARPE marine life agency, the dolphin deaths increased towards the end of January, the AP noted.
Autopsies of some of the more than 870 dolphins found in 2012 were inconclusive, giving way to speculation that the dolphins had died from biotoxins released into the sea, seismic testing, or an unknown ailment.
In an interview with the AP, Yuri Hooker, director of the marine biology unit at Cayetano Heredia University, said that dolphin deaths in other parts of the world have largely been tied to environmental contamination. Frequently the dolphin ingests floating plastic or a fish that itself has been poisoned by toxins, Hooker said.
In Peru's case, determining exactly how the dolphin's died is a challenge due to the fact that the labs in which the necropsies are being performed are only equipped to test for three or four of the 100 or so chemical reagents that can be used to determine the animals' cause of death, the AP reported.
Dolphin die-offs aren't always due to environmental contamination.
In 2013,
more than 1,000 migratory bottlenose dolphins washed ashore after dying from a measles-like virus along the U.S. Eastern Seaboard.
Scientists concluded that the virus outbreak could have been natural and simply cyclical.
Editor's Note: ObamaCare Is Here. Are You Prepared?
Related Stories: