Howdy and welcome to the Forum.
Here are a couple of sites which may help you to answer your question, but in general, the Red River is well known for their Gars.
Kai; Life Member;
South-Texas Chapter Chairman; http://south-texasnafcchapter.lefora.com/forum/ ;
2337 Posts on old Forum/BB;
Atascosa, Texas (just ouside San Antonio)