I was looking at the corps of engineers webpage for grapevine lake and glanced at the lake records page. Looking down the list nothing seemed out of place until I got to the end and it says Red Bellied Pacu. Not a fish I hear commonly so I do a little Google search and it is in the piranha family. How the hell did we get that in grapevine lake? Now I do realize after reading about it that it doesn't have the same type of teeth as a piranha but still it's in the angry fish family. Anyone ever heard of these things?
Yup, people get tired and just dump them into lake or they get too big and they release them. At that point they are too large for most natural predators, so short of environment causing mortality, they live out their life in the lake