Tadpole

The Tadpole is an fish that can be found in the ponds. It appears from March to July. It will appear all day. When selling it to Re-Tail, the player will earn 100 Bells.

Location
The Tadpole is found in the ponds.

The Museum
The Tadpole can be donated to the museum. Upon doing so, the following text is given by Blathers:

"Tadpoles are nothing more than baby frogs and generally inhabit ponds and streams. Their round heads and quirky style of movement give them a different kind of cuteness from adult frogs. They become more frog-like when they eventually grow legs and start to lose their tails. Unlike fish, though, their skin is very delicate because they do not have scales, so handle carefully."

Quote
Upon catching the fish, the player will say the following:

"I caught a tadpole... I'm sure it will grow on me."