Curious how far west do mink and muskrats go? Can they be found in California, Oragon Washington state?

yes

Willamette Valley in western Oregon has/had muskrats if they can hide from the nutria!!

Yea but they are all lefty libs and dont wash.

Rats are abundant in soutern Oregon. Have seen a few thousand at times at the Klamath Falls auction.
Used to be a lot here in the Willamette Valley but the nutria have taken over most of the habitat as Nancy stated.

Mink we have but not in big numbers. Some one with knowledge and time could probably get a fair number but would have to clean out a lot of nutria to get them. Nutes are like coon to water trapper after mink but worse. They will investigate any bank disturbance and will investigate any scent set.

Ted

When I used to buy fur for one of the largest fur brokers in the USA, they would market their Washington muskrats as "Fraser Valley" muskrat. I believe their largest market at the time was Germany. I was told that they where the best 'rats known. There just weren't a lot of them collected in a given year. They had dark backs, blue under fur, and silver bellies, no reddishness.
The area that produced them was SW mainland B.C., and western Washington.
There are pockets of reddish 'rats in the region, but I tried to avoid those areas.

A bit of news from even a little farther west if you're interested. The mainland and islands of se Alaska have very few 'rats, but mink numbers are extremely high. In 1999, I trapped 1-24 December on Baranof, Chichagof, and smaller islands. Only used 24 cubby boxes. Got 102 mink in intertidal zone; no muskrats (some otter and marten).

Jack

^^^^^
I sure wish I knew what your trick is, I find that mink in southern SE aren't all that interested in a baited 120 box; and I've tried all sorts of baits. Trail set are about the only thing that work for me. Maybe mink are hungrier in northern SE.

Game commission reports for eastern Oregon's Harney and Malheur counties showed catches of 50-70,000 rats per year back in the 50's. Droughts have changed all that though.