Here is my journey with the GSF.
100% GSF The damage they will do to your stocking plan depends on how thick they are, how big they are in relationship to the size of the fish you stock.
If the GSF get a head start enough to have big enough mouths to eat the size of the fish you stock, they can devastate a stocking plan. Do some fishing with a #10 or smaller hook tipped with a tiny bit of worm or a Gulp product. Small bait small hook. See what you catch and how big it is.
In my unwashed opinion you either need to up your stocking date if the GSF are very small or if you stock later stock only advanced sizes large enough the GSF can't eat them. Figure a GSF has the same size gape as a LMB the same length. In the thread link I provided I have a picture of a GSF that swallowed a FHM that was 2/3 the length of the GSF with the tail slightly hanging out its mouth.
A baited minnow trap will catch GSF really well. If you want to catch slightly larger ones enlarge the opening from the standard 1" to about an inch and a half. Put parallel to shore line in a foot to two foot depth.
The fish you are holding can easily eat a FHM. The picture I posted was of a fish about 2/3 that size as I recall. If you have a lot of those size and larger, you could loose a lot of the fish you stock if they are only 2". If you go to a 4" size BG to stock, it would take a pretty good size GSF to eat them, though you may already have some that size.
