Is it common to receive some "bonus" species with an order of fatheads? Last year I put one gallon of fatheads into a 1/2 acre shallow (3-4' deep) completely landlocked pond to try and raise minnows and save money. We were not able to seine them out before winter as planned, but they have survived and multiplied. There are no predators in the pond and no other fish were stocked except for some 1-2" redear sunfish two weeks ago.

I put a minnow trap in the pond a couple days ago to check progress and caught several very fat and mature fatheads, a half dozen leopard frog tadpoles and another minnow that dropped into the water before I could get a good look at it. Tonight I caught a redear that looked about 25% larger than I remembered and the same type of minnow from the other night. My best guess from the Peterson Field Guide is that the intruder is a Brook Stickleback.

Is the stickleback commonly found with fatheads? There must be quite a few in the pond to catch one two nights in a row. Is it possible for sticklebacks to colonize a brand new pond in one year by natural means? Did not take a picture but will if I catch another one.