A couple of thoughts: Feeder nectar is a food of convenience. A nesting female may be more interested in bugs to provide protein for her young. Someone, like Bill Hilton on Humnet, that has examined hummer stomach contents may be able to provide insight on this theory.

Having said that, 3 years ago a female nesting in our yard in early February successfully evicted 2 males that had staked out feeders on 3 sides of the house. She was able, without confrontation, to visit feeders that had formerly been territorialized by males. But, the absence of the males may simply be attributed to their moving to more attractive breeding grounds, or finding a more attractive food source, as we see them move out every year, only to return a month or two later to fight with the Rufous. (I doubt that there is any reason to believe that any of the males "chased" from the yard were mates, and even if they were, would they recognize themselves as such?)

For what it is worth, we see females that fight just as vigorously as males to claim and protect feeders. At the time of the snow in November we witnessed a surprising change in yard dynamics as an adult female challenged a male that had claimed and protected a feeder for over 6 months. The feeder she took over was seemingly in a prime location, fairly high off the ground, sheltered, out of the wind and close to a building. The male was exiled to an adjacent feeder (about 15 feet away), where he looked absolutely dejected. Eventually she took over that feeder as well. In a kind of musical chairs, the movement of the first male displaced 2 others from "their" feeders onto feeders on the South and West sides of the house.

I have a question, too. Has anyone documented any evidence of sub-species amongst Anna's?

chuck reinsch, magnolia, seattle, wa

----- Original Message -----
From: Rob Sandelin
To: 'tweeters'
Sent: Wednesday, January 05, 2011 7:23 PM
Subject: [Tweeters] Annas nesting and feeder control


One of my ornithology students asked me some questions I can not find an answer to, so maybe somebody here has some ideas. Since Anna's females raise their young by themselves, and assuming they must incubate the young for considerable periods, does her mate allow her to use "HIS' feeder, or does she have to fend for herself? If the latter, how does she control a feeder against the wishes of the guardian male? Would she be able to battle him for resources? Is there a selection factor here, where males are "easier" on females than on male intruders?

Rob Sandelin
Naturalist, Writer, Teacher
Snohomish County


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