Probably raccoon. You can check out the regulations on the fish and wildlife page. It should not be in season now. Usually is in the winter / early spring. But there may be other critters in season, often vermin are open all year (some people hunt coyotes with hounds):
https://myodfw.com/articles/oregon-furbearer-hunting-and-trapping-regulations
On a side note: Need to be careful what you read online on these bear gall bladders before jumping to conclusions - a lot of animal rights extremists outrage online trying to take down legal hunting with tall tales of poaching and astronomical sums paid for parts.
So, I'd check if something is in season first, then check on the access rights and once you are informed, then alert the authorities accordingly.