Thirteen bald eagles were found dead in a field. This is what killed them.

(Maryland Natural Resources Police) This bald eagle was one of 13 found dead on a farm near Federalsburg, Md., in 2016.The 13 bald eagles were found lifeless on a Maryland farm more than two years ago, many with wings splayed, bodies intact, and talons clenched. Several were too young to have their species’ distinctive white heads. And at least six, according to a federal lab report, had ingested a highly toxic pesticide that has been essentially banned from the U.S. market, in part because it is lethal to birds.

The report, which was obtained by the Annapolis, Maryland, radio station WNAV and shared with The Washington Post, answers one big question in a mysterious wildlife crime that…