I saw this animal on a grassy lawn a few feet from a small stream in Eugene Oregon. It looked rather like a rat, but it was much too large to be a black rat or Norwegian rat. I was about 50 feet from it so it’s hard to be sure, but I’d say it was at least 16 inches long without the tail, the size of a large cat or small dog. It had long white whiskers while the rest of its coat was dark. I think the tail was covered in short fur but it’s possible it was hairless like a rat’s. It seemed to be eating grass, but maybe it was picking out clover or something else. It looked wet, like it had just climbed out of the stream.
It’s a Nutria, introduced from South America.
I wasn’t aware they were in Oregon.
Thick in Western Oregon … and a serious problem … they occupy the niche normally occupied by beavers, which is Oregon’s state animal …
Typical situation, fur-farmers brought them in, fur prices crash, just open the cages … now they’re everywhere …
I always thought they looked like small beavers with just a different tail … my cats are terrified of them …
I made a night delivery down to a factory outside Eugene that has a protected pond and wetland on the premises and the guy in the guardshack warned me to watch out for nutria on the road–and he was NOT kidding around. I saw probably 20 or so just on the short drive to the loading dock and it was kinda freaky because I’d never seen the critters before and they do look like giant rats. I’ve also seen a family of beaver crossing a street in Eastmoreland (neighborhood in Portland) and they were actually using the crosswalk. 
I’ve heard they’re good to eat.
They are definitely here. It’s more than a little disappointing to hike up to the beaver dam off of a trail and find a nutria sunning itself. 
Rodents of unusual size? I don’t believe they exist.
Ees no rrat, ees Siberrian hamsterr!
My pet rats have had a grudge against Basil Fawlty since that episode.
Thanks for the replies. I agree that it was certainly a nutria that I saw.
If it makes y’all feel better, there was a tourist attraction in Ocala, FL (Silver Springs), that had alligator pens, of course, and to make the gators do tricks–and also for feeding–they would band-saw a frozen Nutria in half and suspend it over the gators. Fun, fun, fun.
They’re in Oregon? I’m flabbergasted.
That’s Bill.
When I saw the thread title, before I clicked into the first post, I knew it was a nutria.
I’m not sure why, but in my family somehow “nutria” got changed to “nutrient” and now we say it that way all the time unless we’re expecting to be understood. It amuses us.
We occasionally point them out to the gullible and call them beavers. Eventually the tails are noticed, and we have to explain ourselves. Eventually. 
California is under siege! Apparently they were presumed eradicated here in the 1960’s, but they have returned to wreck their vengeance on the CA waterways.
aka coypu.
Yep, Washington, Oregon, the eastern seaboard, and particularly Louisiana (millions of them), among other places. Their burrows and plant consumption are detrimental to plants and animals, as well as causing soil erosion.
I recently learned about the efforts in the Blackwater NWR, eastern Maryland, that almost completely wiped them out.
Darn sure I saw them in Texas two years ago; Port Aransas area (Gulf Coast near Corpus Christi).
They are in the resaca around Brownsville in Texas.
They eat them in Louisiana. Mr.Wrekker has been on a hunt for them in Houma,La., after Katrina they were everywhere down there. He did say he didn’t eat any cause they live in sewers and nasty bilge water. They swim like fishes.
Wonder how the taste compares toCane Rat. Delicious, tender Cane Rat…