Stringfish

The Stringfish is an extremely rare fish that appears in the winter (December to February), from 4pm to 9am. It is caught in the river. It sells for 15,000 Bells, making it one of the most expensive fish in the game. Its scientific name is Hucho perryi and its real name is Sakhalin taimen. In City Folk, the 'Bug and Fish' window describes it as 'Rarely seen and treasured, these are known for having voracious appetites.'

In Animal Crossing
"Hoo! Indeed, WOO hoo! This is an extremely rare fish, I'll have you know! I'm absolutely agog! If I may hazard a guess, this must have been the most difficult fish to catch yet! I almost can't believe it! To think, you're donating such a rare find to us... Allow me to commend you on your matchless generosity. We've been saving a place just for this day, wot wot! Have faith, this fish will be thoroughly treasured!"

In Wild World
This is Blathers's speech about the newly donated fish:

"Hoo! Indeed, WOO hoo! A stringfish! I've heard it said that this fish is actually very high in fat content... If such words are true, then whatever possessed someone to name it that? If you were to call a portly fellow "stringy," well... Madness would ensue!"

The stringfish can be found in the middle tank in the aquarium.

In City Folk
Blathers will tell you the following about the fish upon donation to the Museum:

"...Stringfish are hardy creatures that can live for up to 15 years with ease! These older fish grow to remarkable sizes actually... One fish even made it to a gargantuan 80 inches! At that size, perhaps we should call it the king of the river! No wonder it looks so serene, eh wot?"

The stringfish can be found in the middle-left tank in the aquarium.

Fishing Tourney
Chip will not eat this fish if you give it to him as an entry for the Fishing Tourney. He will mention that it is too special to eat as it is. He will accept it as an entry and will measure it as usual.

Further Information
Hucho perryi is one of the largest, most ancient type of salmon species which inhabits the lower to middle reaches of lakes and rivers. It is Critically Endangered. Females lay between 2,000 - 10,000 eggs each time on sandy/gravelly river bottoms, most of them do not hatch. The fish can be found in areas of the Northwest Pacific, namely the Sakhalin Island (Russia, where it gets the name Sakhalin taimen), the Island of Hokkaidō (Japan) and parts of the far eastern Russian mainland.