Bluebirds and tree swallows fight it out in the air, the bluebirds flying straight at the swallows, while the swallows circle in diminishing arcs eventually threatening to strike their foe. The battle for the house may continue for several days:
May 29, 2004 52 degrees at 10am. Mr. Bluebird is staking a claim on the Front House, but Mrs. is nowhere to be seen. So far, the tree swallows are also absent. Mr. perched on the post about 1pm, looked about for several minutes, dropped down to the top of the house, looked some more, then dropped to the perch on the front of the house. Very warily, he then leaned forward and, for barely a microsecond, poked his head into and out of the opening. He looked around again, then went in for another microsecond view. He repeated this a third time, then flew to the apple tree and then the wire.
The next morning (May 30), Mr. and Mrs. Bluebird were both here – and so was a tree swallow. By the 31st, the battle for the bird house was in full sway. At 10am, the tree swallow stuck his head out. At 1010, the bluebird approached and the swallow flew out at him. After five or ten seconds of very close order chasing, they fell to the ground for a few seconds of pecking and wing flapping, and then the bluebird flew away. On June 1st, the tree swallows seemed to have control over the bird house.
Sometimes the bluebirds win, sometimes the tree swallows win, and sometimes the house wrens win.
May & June 2011: Bluebirds Victorious
In 2011, the bluebirds won the house, but they continued to worry about intruders for another month:
May 7, 2011. Bluebirds were fighting off tree swallows at the Front House.
June 16, 2011. A chipmunk was trying to cross the lawn from the grunkle behind the bird house, but the manly bluebird didn’t want him to. Each time the chipmunk ventured forth, blueie swooped from his perch atop the Front House and buzzed the rodent, hovered, and buzzed him again until he scampered back to the weeds. This happened again and again, with the same result, until, on the tenth try, the chippie tore ass right out of the gate, ignored the dive-bomber, and continued at high speed to the safety of the driveway. The bluebird was so defensive, because its hatchlings were about ready to become fledglings – which happened on the next day.
May 2020: Tree Swallows Victorious
In early May 2020, a pair of tree swallows and an extra male were interested in the Front House:
May 7, 2020, 55 degrees, sunny. A pair of tree swallows are in the Front House. The female seems to like the house; she flies around for a while, then returns to perch on the post, once going in, but usually staying a few minutes before flying off. At first, a male was at the house with her; then he perched by the patio. A little later, a second male came in, and the three of them circled up, around, and over the houses – theirs, ours, and Sally’s on the other side of Post Road. I think the males were establishing dominance or demonstrating their maneuverability, while she circled somewhat apart, enjoying the spectacle as much as I did. However, three minutes was enough for this. She returned alone to her house, the males disappeared, and I returned to my coffee and my spelling bee.
A week later, the apartment was still available for rent, the tree swallows were still interested, but so was a bluebird:
May 13, 2020. Two pairs of tree swallows and a male bluebird checked out the Front Yard House today.
It was another week before the tree swallows decided to take possession:
May 16-17, 2020. Blackflies abound. Tree swallows are building a nest in the Front House.
Although they were no longer bothered by the bluebirds, the swallows remained wary of any potential competitors:
May 20, 2020, 74 degrees, breeze, no clouds, 3pm. A brown thrasher acted like a robin looking for worms and insects on the front lawn. After a couple of minutes, it was chased away by a swallow from the Front House.
I noted no further problems, and in another couple of weeks, the eggs were about to hatch:
June 2, 2020, partly cloudy, 65 degrees, no wind, 930-1000am. The tree swallows in the Dam House and the Front House seem to have eggs that have already hatched or are about to hatch.
2019 & 2012: House Wrens Victorious
If the bluebirds and tree swallows aren’t careful, a pair of house wrens may slip into one or more of the birdhouses. If they find an unoccupied house, they quickly stake their claim – by filling the house up with twigs! Since no self-respecting bluebird or tree swallow wants a living room filled with twigs, the wrens will retain custody:
May 5, 2019. The first wren was at the front-yard house. Two minutes later, a tree swallow flew high overhead before descending in a half-dozen ever lower and ever diminishing arcs, eventually landing on the wren’s house. The swallow just peaked in and then departed. Two minutes later, the wren returned, inserting one stick and then another, then disappearing for a half hour before coming back to resume building its nest.