https://www.atlasobscura.com/places/salida-fur-bearing-trout

Throughout history, legends of strange and wild mythical creatures have brought curious cryptozoologists to the western United States. While full specimens of larger and more dangerous cryptids like Sasquatch and the Chupacabra are exceptionally rare, there is one animal that seems to be commonly displayed in homes and businesses across the West: the fur-bearing trout.
Reports of fur-covered fish date back as far as 17th-century Iceland, but one of the earliest American sightings occurred along the Arkansas River in 1938. According to local lore, the frigid waters flowing down from the Colorado Rockies caused otherwise ordinary trout to evolve warm coats of fur. In the summer months, the fish would shed their hair, appearing indistinguishable from any other trout.
These tales originated with Wilbur Foshay, a con man freshly released from prison who somehow landed a position as manager of the Salida Chamber of Commerce. Tasked with drawing money and visitors to the small mountain town, Foshay convinced newspapers to print stories about the capture of several specimens. The “fur” looked suspiciously like rabbit or muskrat pelts wrapped around hairless trout, but the papers ran the stories anyway. Alongside tales of furry fish, Foshay promoted Salida with billboards of scantily clad women holding signs that read: “Follow the Hearts to Salida.” This latter tactic, while less imaginative, may have been more effective.
Whether due to global warming, overfishing, or simply the fact that fish aren’t mammals, the fur-bearing trout is now thought to be extinct. The oldest surviving specimen, allegedly caught (or fabricated) by Foshay himself, is displayed at the Mt. Shavano Fish Hatchery in Salida, alongside several of the original newspaper clippings that helped put the furry fish - and the town - on the map.
https://www.atlasobscura.com/places/salida-fur-bearing-trout