I have been living on my 12 acres for 10 years. It is mostly woods and has sinkholes everywhere. Pretty much all the rainfall in the area is drained by sinkholes and the creeks are few and far between. Three of these sinkholes on my property will hold water year round during an average to wet year. The widest one is maybe 1/4 acre but shallow. It lies right on the backside of the dam of a 5+ acre lake owned by a sporting club I share a border with. The lake doesn't overflow into this small hole but does into a different sinkhole on my ground that don't hold water. All three of these holes have no outflow of water as there has never been enough rain to fill them to the edge of there respective holes (and this has been the 3rd wettest spring on record for our area.) There is no way fish can get into these holes by swimming upstream or downstream as there is no "stream". These holes all have had turtles, frogs, and get visited by herons. I have never seen any fish in these holes since I have lived here. Only last year did I begin to plant fish in them to keep mosquitoes down.
At my parents pond we had to build a concrete spillway "chute" with a small waterfall to keep the bullhead out of their pond. Even with this in place I have found 1 inch bullhead working themselves to exhaustion working their way up the chute. Luckily we have never caught one in the pond so they have not been successful yet(20+ years). I think 99.9999% of fish swim their way into new ponds instead being delivered by air. Since they can't swim their way into my sinkholes they don't show up.
