[philipw2]

As those of who you read my earlier post know, I have been having a hard time attracting birds to my feeder. Recently I have noticed a northern mockingbird guarding the feeder, swooping down--often at great speed--on smaller birds if they approach the feeder. Sometimes if a smaller bird is on the ground below feeding on the droppings, the mockingbird will check it out, driving the other bird away.

So now my bird feeder is reduced to a single mockingbird and, of course, the squirrels.

I have heard about hummingbirds becoming territorial against other hummingbirds at feeders. How frequently does this kind of behavior occur? Is aggression against other species common?

[Toucha kent]

yes, the humming birds are very territorial. Every time one comes to feed another runs the first off. I have been watching them closely the past couple of days. and It seems Im observing the same things you are.

Toucha

[mkdon]

You are correct. Hummingbirds are aggressive and territorial. A male (usually) will claim a feeder or a yard and chase off all other hummers. The usual answer is to hang two feeders out of sight of each other. Maybe that will be the answer to your other aggressive visitor. Mockingbirds have been known to chase cats and even dogs. They will not hesitate to divebomb people as well. Maybe another feeder out of sight of the one the mockingbird has claimed could help.