Bucky O'Hare & The Toad Wars (or, Toad Menace as it was known outside the US) was a spin-off from a comic book created by Larry Hama (G. I. Joe) and Michael Golden, and published by artist Neal Adams' Continuity Comics. Airing on Sundays in much of the country in its lone season (1991-2), Bucky didn't get the attention some folks might think he deserved. I never saw the show, so there won't be a rating.
Anyway, the opening episode explains how a young human named Willy joined the crew captained by Bucky, a green-furred rabbit.
The comic book itself was a spin-off, as Bucky debuted in 1984 in an anthology book, but the relative infrequency of publishing might also have had something to do with the television show's failure.