I have three ducks that free range in a fenced in open area. The pond is large (probably 50' x 30' roughly) with a fair amount of grassy dry area as well. I've been giving them Duck Grower, but I think chipmunks or mice are "assisting" them with eating it. I can't imagine three ducks ate a full 20 gallon feeder in 4 days... What I'm wondering is whether so few ducks in such a large space would be able to forage enough on their own? I hate paying to feed the wildlife and not the ducks! Lol. Thanks!