From Nookipedia, the Animal Crossing wiki
Chip (うおまさ, Uomasa) is the beaver that runs the fishing tourneys. His name might come from the dish fish 'n' chips. Chip sets up tent early in the mornings (at 6:00 A.M. sharp, but he will not accept submissions until 9:00 a.m. in City Folk and New Leaf) and waits for players and villagers to bring him different types of bass (small bass, bass, and large bass) to measure at the weigh-in station. If an eligible fish is brought, Chip will measure it by chewing it up inch by inch. Every time a fish is brought in that breaks the current tourney record for the day, he will give an item for a prize. If players hold the biggest fish record by 6 p.m., Chip will send an additional reward in the mail. Chip will always post the winner of each tourney to the bulletin board. Although beavers are herbivores, Chip is shown eating the fish. He does not eat special fish, such as the Stringfish, but still accepts them as entries.
In Wild World, Tortimer assumed the role as judge of the fishing tourneys, thus Chip did not appear in that installment. However, he returns in Animal Crossing: City Folk and Animal Crossing: New Leaf with a deeper voice than before. In these games, he does not ask for bass, but instead he alternates between tourneys where any type of fish is eligible, and tourneys where he asks for a specific (usually common) fish.
In City Folk
In City Folk, he sets his stand at the Town Hall. Chip hosts the event based on one specific type of fish. If the player gets all the types of fish, he will give the player a golden fishing rod. Fishing Tourneys occur one Saturday a month in all months except June, July, August, and September.
In New Leaf
In Animal Crossing: New Leaf, he hands out furniture from the Fish Set when a large-record fish is given to him by the player. Furthermore, he no longer set his stand in the Town Hall, but he can be found in the Event Plaza. Chip hosts the awards ceremony between 6 p.m. and 9 p.m., handing out gold, silver and bronze trophies to the winners, and gives the player a golden fishing rod if they show to him that they have caught every type of fish.
Chip appears as a collectible trophy.
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