Officials in Oregon are asking for public assistance to locate the person or persons responsible for poisoning eight wolves in the eastern part of the state earlier this year.
The Oregon State Police has been investigating the killing of all five members of the Catherine Pack in Union County, plus three other wolves from other packs, the agency said in a press release Thursday.
"To my knowledge this is the first wolf pack to be killed by poison in Oregon," said Capt. Stephanie Bigman of the OSP in Salem. "To my knowledge there are no suspects. All investigative leads have been exhausted and that is why we are reaching out to the public for assistance."
Wolf advocates were stunned by the news.
"This is horrific," said Sristi Kamal of Defenders of Wildlife in Portland. "This is quite clearly an intentional and repeat offense."
Oregon has only about 170 wolves within its borders, and the loss of eight "is so egregious," Kamal said.
"The poisoning of the Catherine wolf pack is tragic and disgusting" said Sophia Ressler, a staff attorney at the Center for Biological Diversity. "No wolf should have to suffer such a fate. Awful events like this show how much more work is needed for us to coexist with these vitally important animals."
Wolves once ranged most of the U.S. but were wiped out in most places by the 1930s under government-sponsored poisoning and trapping campaigns.
More than 2,000 wolves occupy six states in the Northern Rockies and Pacific Northwest after animals from Canada were reintroduced in Idaho and Yellowstone National Park starting in 1995.
However, wolves remain absent across most of their historical range. Wildlife advocates argue that continued protections are needed so they can continue to expand in California, Colorado, Oregon and other states.
The Fish and Wildlife Division of the Oregon State Police was alerted on Feb. 9 that a collared wolf from the Catherine Pack was possibly deceased.
Troopers responded and located five deceased wolves, three males, and two females. The wolves were located southeast of Mount Harris, within Union County. Investigators also found a dead magpie in the vicinity of the dead wolves, the agency said.
The animals were sent to the U.S. Fish and Wildlife Service forensics lab in Ashland to determine the cause of death.
On March 11, State Police were told a mortality signal from an additional wolf collar had been received in the same general location. Searchers found a deceased female wolf, a skunk, and a magpie all very close to the scene. The female wolf was determined to be a member of the Keating Pack.
In April, the federal lab released findings consistent with poisoning as the cause of death for all six wolves, the skunk, and two magpies.
In addition, two more collared wolves were found deceased in Union County after the initial incidents. In April, a deceased adult male wolf from the Five Points Pack was located west of Elgin, and in July a young female wolf from the Clark Creek Pack was located northeast of La Grande, the county seat.
Toxicology reports confirmed the presence of differing types of poison in both those wolves, the OSP said.