By Alex DeMetrick

BALTIMORE (WJZ) — More reward money is being posted in the death of 13 bald eagles. The birds were found on Maryland’s Eastern Shore last month.

Alex DeMetrick reports $30,000 is now being offered to find the suspect.

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Thirteen dead bald eagles showed no obvious signs of trauma.

The U.S. Fish and Wildlife Forensics Lab in Oregon ruled out natural causes, like disease, moving the investigation to poisoning as the possible cause of death.

“To think that they could be deliberately poisoned is just very bothersome, and we don’t want to see that, we want to see it stopped,” said Mike Parr, American Bird Conservancy.

So the American Bird Conservancy is offering a $5,000 reward, bringing a combination of rewards to $30,000.

“And see if a prosecution can be brought if indeed a criminal activity was involved,” said Parr.

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The 13 eagles were found near Federalsburg in February. All were in a large open field, possibly killed with poisoned bait. Scavengers, eagles will eat other dead animals.

The hunt for a suspect comes at a time bald eagles are drawing a lot of attention.

An up-close look at a pair of nesting bald eagles at the National Arboretum in Washington, D.C.  on a web cam drew millions to watch.

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And last weekend, two eaglets were hatched into the world–but what kind of world?

“Everybody’s very excited about that, and the idea that those eaglets could be hatching and flying out into an environment where they might be poisoned deliberately is something that I think a lot of people are outraged about,” said Parr.

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The U.S. Fish and Wildlife Service is the lead investigator in the case, supported by Maryland ‘s Natural Resources Police.