A Washington man accused of killing more than 3,600 protected birds, including bald eagles, and selling them on the black market has reached a plea agreement with prosecutors.

Travis John Branson of Cusick, Washington, on Tuesday filed a motion to change pleas and an accompanying plea agreement in federal court in Montana. As part of the agreement, the 48-year-old will plead guilty to two counts of unlawfully trafficking bald and golden eagles, one count of conspiracy and one count of violating the Lacey Act, a law that bans the trafficking of illegally taken wildlife, fish, or plants.

In exchange, prosecutors have agreed to drop 10 counts of unlawful trafficking.

Branson's attorney declined to comment.

Meanwhile a second man charged in the case remains at large as of Tuesday, according to the Associated Press. An arrest warrant was issued in January for Simon Paul of St. Ignatius, Montana, after he failed to appear for a scheduled court date.

Paul's lawyer declined to comment.

'On a killing spree'

According to an indictment filed on Dec. 7, the hunters illegally shot the birds on the Flathead Indian Reservation in western Montana and elsewhere and sold parts or all of the eagles between January 2015 and March 2021.

The killing of bald and golden eagles is a violation of the Bald and Golden Eagle Protection Act.

According to court papers, in December 2020, Branson sent a text with a picture of a golden eagle tail set to a buyer and got a PayPal purchase that same day. Two days later, he shipped the set to Texas, and a couple of days later, he received a PayPal payment for it.

Prosecutors said Branson and Paul also allegedly used a dead deer to bait eagles so they could shoot them.

Court papers say Branson also reportedly bragged about going "on a killing spree" and about the "significant sums of cash" the pair made from the sale of the slaughtered birds.

If convicted of all charges, Branson could face up to 13 years in prison. The court still has to approve the proposed agreement.

Paul, 42, stands accused of one count of conspiracy, 12 counts of unlawful tracking of bald and golden eagles and one count of violating the Lacey Act.

Black market for eagle parts

A recent study by the U.S. Geological Survey found that the illegal shooting of golden eagles is a leading cause of deaths for the protected birds.

Of particular value are feathers from immature golden eagles, which are revered among tribes, according to reporting from the AP. A tail set from a golden eagle can fetch several hundred dollars, according to details in another trafficking case last year, AP reported.

Contributing: Sarah Al-Arshani