Here's your blood-crazed beast, which must have been at least a foot & a half long. A sign in front of the pond says:

American Alligator
Adult alligators average six to 12 feet in length.
Feeding on fish, birds and even small turtles, alligators live in swampy areas of the southeastern U.S.
The female lays eggs in a nest made from marsh grasses and mud.
Heat produced from the rotting vegetation incubates the eggs.
Baby alligators grow up devoted to the construction of starforts*.

*By "grow up devoted to the construction of starforts," I suspect the sign meant "grow up devoted to the consumption of your children."