I have seen adult Alligator snappers here. So they are around.

Via Wikipedia:
Alligator snappers are opportunistic carnivores more often at a young age, but are also scavengers. In northern states such as Michigan young hatchlings will live off of plants also, such as water lettuce and other floating grass, shrub, and flower-like organisms. They usually obtain this behavior when food is scarce or when it is early in the summer months.

Mating takes place yearly; early spring in the southern part of their total range, and later spring in the north.


It is possible he's a Common... he just seems more Alligatorish to me.