A Utah resident is facing up to a year in prison for shooting an elephant seal on a beach in California. The elephant seal is protected under federal law as part of the Marine Mammal Protection Act.

The man – identified as 30-year-old Jordan Gerbich – admitted to the shooting and pleaded guilty on Tuesday. He was charged with one count of killing a protected marine mammal.

The U.S. Attorney’s Office for the Central District of California said that prosecutors had recommended that the man serve a six-month prison sentence. A tentative plea agreement requested that three of the six-month term be served under house arrest.

The charge – a federal misdemeanor – carries a maximum sentence of one year. A judge will need to determine the man’s final sentence during a scheduled hearing in April next year.

Gerbich’s motive to shoot the elephant seal remains unclear. According to court documents, Gerbich drove to a viewing area near San Simeon on California’s central coast armed with a .45-caliber pistol. He then proceeded to shoot the seal, which was lying on the beach.

The National Oceanic and Atmospheric Administration said that they discovered the seal dead on the beach with its tail fins cut off. It was shot in the head. The agency then proceeded to offer a $20,000 reward for information that would lead to the perpetrator.