In all of my visits to zoos I can't help but notice all of the Canada geese and mallards that like to land in the available open water. Out of curiosity, do zoos actually feed these birds? I can see that birds in exhibits with animals like elephants probably wouldn't be too interested in hay, but what about the ducks and geese that land in waterfowl exhibits? Do the keepers chase them off when they feed the captive birds? Also, does anyone know if any of the wild birds have ever bred with captive birds? As I understand mallards in particular are known to hybridize with other species of ducks even in the wild.