An endangered wolf named Rusty was shot dead by the U.S. Fish & Wildlife Service (FWS), leaving behind his pups and a likely pregnant mate.

The Mexican gray wolf, reportedly killed on April 12th, was a part of the Mangas Pack, who reside in New Mexico near the Arizona border in the northern Gila National Forest.

Government officials quietly approved the killing of Rusty in March, alleging a connection to attacks on livestock in the area. Officials reportedly refused to listen to advice from scientists, who recommended non-lethal alternatives — such as requiring farmers to remove the corpses of livestock not killed in depredations to deter wolves from scavenging.

Wildlife advocates are mourning the death of Rusty and warn that the killing will likely have detrimental consequences.

“This is a sad day for Mexican wolves and a devastating loss for the Mangas pack, which could be welcoming pups at any moment,” said Maggie Howell, the executive director of Wolf Conservation Center, in a press release. “Apart from this endangering the Mangas pack’s survival, science has shown that removing a wolf parent from the family can destabilize the pack and increase the likelihood of further conflicts.”

Environmental advocates are condemning the cruel killing, too.

“Every single time a Mexican wolf is killed by the agency meant to protect and restore lobos (wolves), we need to remember: These are critically imperiled, native, ecosystem engineers who belong in the wilds of the American Southwest,” said Chris Smith, the southwest wildlife advocate for WildEarth Guardians.

Wolves are family-oriented and intelligent individuals who don’t deserve to be shot dead for existing. Instead of protecting profits, wildlife officials need to protect wild animals — not gun them down. Take action to help other wolves today by signing our petition to stop the massacre of wolves in the United States.