It wasn't a personal attack. If you were BSing, then you are guilty only of exaggerating what a fish eats. And ignorance is easily cured by a little reading (whereas stupid is permanent).
Based on a study I found, I would guess that gar selectively eat drum and other gar rather than LMB.
I did a little after reading your post and found this which was published by the Lower Mississppi River Conservation Committee (
http://www.lmrcc.org/Library/498gar.html):
"Alligator gar are large (sometimes well over 200 pounds), fish-eating predators found throughout Louisiana's freshwater habitats and even the state's brackish marshes. One look at the gar's mouthful of needle-sharp teeth is often enough to convince fishermen that they are fish-eating machines that can damage sport fish populations.
Texas biologists did a food habits study on this fish in Sam Rayburn Reservoir to see just what they do eat. During a two month period in September and October they caught 209 alligator gar with gill nets and jug lines. The gar ranged in weight from 18 pounds to 156 pounds.
While most of their stomachs (126) were empty, enough had food in them to get a picture of their diet. The proportion of food items by species is listed below:
SPECIES
% OF TOTAL FOOD ITEMS
Gizzard shad 26.4%
Channel catfish 14.9%
Freshwater drum (gaspergou) 12.6%
Bluegill, redear, and goggleye sunfish 7.9%
Spotted sucker 6.8%
White bass (barfish) 4.5%
Largemouth bass 3.4%
Spotted gar 3.4%
Crappie (sac-au-lait) 2.2%
Lake chubsucker 2.2%
Carp 1.1%
The study also showed that gar can be scavengers, as the carcasses of 7 crappie discarded by fishermen after cleaning were found in their stomachs. Other items found included 2 coots, 11 fish hooks, 1 artificial lure and 1 plastic bag."
Of the above species, I would classify the following to be large fish predators:
Channel catfish 14.9%
Freshwater drum (gaspergou) 12.6%
White bass (barfish) 4.5%
Largemouth bass 3.4%
Spotted gar 3.4%
I don't have data on what the population of these predators is in Sam Rayburn, but I would expect it to be something like:
Channel catfish 20%
Freshwater drum (gaspergou) 10%
White bass (barfish) 30%
Largemouth bass 20%
Spotted gar 8%
Hybrid striped bass 10%
Alligator gar 2%
Note that I added in hybrids based on the fact that TPWD says there is good fishing at SR and I added gator gar based on the fact that they must be there if the study was done on them.
Since there are more LMB in the lake than drum and gar, then the big gar must be selectively eating the drum and gar as the stomach studies indicate 5 times the amount of LMB in the stomachs. Note that the gar are not eating a lot of carp, but do eat lots of suckers and in fact eat 3 times as much carp and sucker as LMB.
This diet should help to create a fishery with large predators at the expense of small predators, suckers, small gar, and drum.
It would be great if someone could populate the fish populations with real numbers rather than my estimates.
I hope that TPWD does some real analyses when coming up with its regulations rather than going with second hand anecdotal evidence from my brother-in-law's great uncle's sister from Nebraska.
A Texas Game Warden told my about the alligator gar many years ago.
