More than 2,000 dead penguins washed up on Uruguay's coast. A bird expert says they can't pinpoint a cause.

• Over 2,000 dead penguins have washed up on the shores of Uruguay.
• The birds have tested negative for the avian flu, leaving experts guessing at causes of death.
• Environmental experts suggested overfishing practices could be to blame.

A mysterious and alarming scene has greeted beachgoers of eastern Uruguay for the last ten days, as about 2,000 penguins have washed up dead for no discernible reason.

According to reporting from The Science Times, the birds, which are Magellanic penguins, have all tested negative for the avian flu, ruling out a common cause of mass death in bird species.