Duck love

We have a lot of ducks that hang out in the ponds (read: drainage ditches) in our neighborhood and Calvin's day just isn't the same if he doesn't get to go say hi to them.  It's really a good time, because some people, ourselves not included, clearly feed these guys and they are more than happy to waddle within touching range as we stroller on up.  For some reason, however, they aren't so happy to stay that close when Calvin is no longer restrained in the stroller, a fact that confuses and frustrates the poor child to no end.  The dogs and cats let him pet them, why not the ducks?  Come on!