Thanks for the replys, didn't realize the sticklebacks were so common. I doubt they produce offspring at a rate that rivals the fathead, but diversity within the forage species should be a good thing. I've also noticed a few small freshwater clams in that pond, which apparently came in on the fish as glochidia. It's amazing how fast the food chain builds up. We had a pretty good mayfly hatch on that 1.5 year old pond yesterday.