May 04, 2022
Melissa’s mom had set up a bird house for the blue birds that frequented our patio to nest. When we arrived, the blue birds continued to nest in the house. The birds would come in the spring and reestablish their nest, then leave after the hatchings were gone. Other birds began to take an interest in the house at the end of last year, along with a squirrel. This spring we saw several contests as various species tried to gain control of the house. This became a daily battle between the blue jays, mockingbirds, blue birds, and house sparrows. Eventually the sparrows seemed to win and established their nest, but the battle for space continued. After last night’s storms Zena was taking particular interest in snuffling my new tomato plants. I saw the nest material had been partially pulled out of the entrance hole to the house and I knew something was wrong.
When I looked online, I found that northern mockingbirds (Mimus polyglottos), blue jays (Cyanocitta cristata), and red squirrels (Sciurus vulgaris) are all known to attack and eat bird eggs, nestlings, and occasionally kill adult birds. Mockingbirds can be very aggressive and will attack and even kill other birds if they feel their nests or babies are threatened. Mockingbirds will kill other birds in defense, but they are not likely to kill birds to eat them. Blue Jays are very territorial and will chase other birds from a feeder for an easier meal. They may raid other birds’ nests, stealing eggs, chicks, and nests, but this is not common. Squirrels go as far as raiding a bird’s nest for food, and the red squirrels are the most carnivorous. They can climb into the nest or birdhouse holes and get to the eggs and chicks. Nesting birds under attack by a squirrel often abandon their nests, leaving their eggs and chicks at the mercy of the squirrel. If they do not flee, the adults are occasionally killed. All three were possible suspects.
Zena continued to snuffle the tomatoes beneath the bird house despite my calls, so I went over to see what had caught her interest. One of the adult house sparrows (Passer domesticus) was lying dead in the container. Zena did not try to eat the bird, but she was interested in this motionless animal. I thought it best to remove the carcass to keep Zena from further exploration in the tomatoes. While I was at it, I decided to clean the nest material from the bird house. The amount of nest pulled through the hole suggested the interior was filled with nesting material. You need to use gloves to do this and thoroughly wash your hands afterwards to avoid diseases. When I opened the nest box, I found I was right. It was full of old nest.
THOUGHTS: I have read you should clean your bird house at least once a year, and preferably twice. This allows potential occupants to start with clean fill for their nest. I have been lax in this, and that may be why the blue birds chose not to nest this year. Unlike the aeries built by eagles over years, smaller birds generally build a new nest and the old ones tend not to survive the winter. During the pandemic many things have been allowed to accumulate. Perhaps we should clean out the old nest (ways) and make a fresh start. Act for all. Change is coming and it starts with you.