TRAVERSE CITY (AP) - A gray wolf that fled Isle Royale National Park across a Lake Superior ice bridge and was found dead on the mainland had been shot with a pellet from an air gun, officials said.
The 5-year-old female, nicknamed "Isabelle" by researchers who monitor wolves and moose on the island park, was described as a loner that had been bullied by other wolves.
She escaped this winter, seizing the rare opportunity to traverse at least 15 miles of ice separating Isle Royale from an area along the U.S.-Canadian border. Isabelle's body was found Feb. 8 along the Minnesota shoreline on property owned by the Grand Portage Band of Lake Superior Chippewa.
There were no visible wounds, and scientists initially said she apparently hadn't been shot. But the pellet showed up during an X-ray, and a necropsy showed it had caused fatal internal damage.
The pellet was a type used typically to hunt small animals such as squirrels, said Phyllis Green, the park superintendent. That suggests the shooter may have been trying to scare off the wolf instead of kill it, she said.
Green described the wolf's death as "a fluke thing" that resulted from the pellet striking Isabelle between two ribs and entering her chest.
"If the pellet had hit just a half-inch to the left or right, the outcome may have been less significant," said Margaret Wild, the National Park Service's chief veterinarian.
The Colorado State Veterinary Diagnostic Laboratory teamed with the park service on the necropsy.
An investigation concluded the shooting happened on tribal land, Green said. The Grand Portage Band prohibits hunting or trapping wolves on its territory but allows people to chase away or kill those creating a nuisance, she said.
Because it appears no rules were violated, the park service won't try to identify the shooter, she said.
A message seeking comment was left with the tribal chairman's office.
The tribe turned over the carcass to the park service, Green said. It will help biologists with Michigan Technological University, who have studied the island's wolves and moose for decades, to learn more about the condition of island wolves, which are severely inbred.
An initial examination showed Isabelle did not have rabies or canine distemper virus, Green said.
Wolves initially made their way to Isle Royale in the late 1940s, probably across a similar ice bridge. They've helped keep the moose population in check, preventing them from overbrowsing park vegetation.
Wolf numbers reached 50 decades ago but have fallen sharply in recent years and now total only nine. Michigan Tech biologists Rolf Peterson and John Vucetich have called for bringing more wolves to the island to deepen the gene pool and prevent them from dying out. Other scientists say nature should take its course.
The park service is weighing its options, Green says.