WILDLIFE --  An Oregon congressman is asking the Interior Department to work with states to curb gray wolf hunting around Yellowstone National Park in Wyoming and Montana.

Rep. Peter DeFazio is the ranking Democrat on the House Natural Resources Committee.

Hunters have legally killed Yellowstone wolves that have roamed out of the park after becoming familiar with wolf-watching tourists. Some of these wolves have been radio-collared by wildlife scientists. While killing them is legal under hunting regulations, the loss is significant to research on the species.

DeFazio said in a recent letter to Interior Secretary Sally Jewell that hunters killing wolves just outside Yellowstone’s boundary could hurt the overall health of the park’s ecosystem.

DeFazio asked for a “wolf safety zone” or buffer around the park, which includes parts of Montana, Wyoming and Idaho. He also asked Jewell to establish a task force to devise protections for wolves around other national parks.

State officials have resisted prior calls from wildlife advocates seeking an outright ban on wolf hunting around the park. However, quotas in some areas limit how many can be killed annually.