Friday, May 30, 2008
This morning, I wrestled down the aluminum pool-cleaning pole off its usual hook in our garage. No, I wasn't cleaning a pool; I was monitoring bluebird nest boxes. The normal person would not associate a pool-cleaning pole with bluebird monitoring, but the pole is an essential part of the California bluebird monitor's kit. Out here, virtually all bluebird boxes are hung in trees; it is much cheaper and easier than mounting the boxes on posts. Additionally, the boxes are less noticeable and are less likely to be disturbed by curious humans.
If this were not odd enough, I make rather unorthodox nest boxes. I drill two entrance holes into the front of the box, instead of a single hole. This allows an incubating female bluebird (or nestlings about to fledge) to escape the box in the event of an attack by a House Sparrow or other predator. Also, these boxes are jumbo-sized; twelve inches tall, with a floor of about 6" x 5 1/2". This roomy interior allows the young bluebirds to spread out a bit so they aren't piled on top of each other in the nest.
I carefully caught nest box #1, located in a greenbelt right behind my house, in the wire basket attached to the end of the pool-cleaning pole. These wire baskets are designed and made by Dick Purvis, master bluebirder of Southern California. I flipped the latch and opened the box - nothing except bare wood. But that's what I expected. I just hung this box last week, and it might take awhile for a pair to find this new box. I replaced it on its branch and continued onto the next box.
Two angry adult bluebirds dove at me and snapped their bills angrily as I lowered their nest box. Their hearts, however, were not really in it. They know the routine by now. I peeked inside - five eggs! Two more than last week. I quickly hooked box #2 back on its branch and walked away. The female bluebird flitted back in as if nothing had happened.
As I approached my third and final box, the male bluebird scolded from nearby but didn't dive-bomb me. When I peered into the box, the coal-black eyes of the female bluebird glittered back up at me as she crouched on her eggs. She didn't budge. I snapped a couple quick photos before closing the box and hanging it back up. Many female bluebirds won't move off their eggs when the box is opened; I never cease to be amazed by their boldness.
So, if in the next few weeks you hear poundings, sawing sounds, and frustrated expletives coming from the garage, that will be me making more bluebird nest boxes. :-D