A Texas oil company has agreed to plead guilty and pay a $1,000 fine for killing a duck during drilling operations in western North Dakota.

Dallas-based Petro-Hunt LLC was charged under the Migratory Bird Treaty Act for the death of a northern shoveler found May 6 in one of the company's waste pits. Under a plea agreement filed in federal court Friday, Petro-Hunt will pay the fine to the nonprofit wildlife group.

Two other oil companies charged with killing birds during drilling operations in North Dakota have pleaded guilty and have agreed to pay fines. Three companies have pleaded not guilty.

U.S. Attorney Tim Purdon said he could not comment on plea deal because it still must be approved by a judge. Petro-Hunt did not immediately return telephone calls.