Migration is underway, if somewhat slowly because of the cold weather and snow. Yet interesting observations are made daily. The highlight of the week came in the few hours we were able to open the nets and captured a Townsend’s Solitaire – only the fifth time we have banded this species since 1994!
Other bird species, like American Crows, are already building their nests for the season. As more migratory species start looking for a place to raise their young, now is the perfect time to clean out your bird boxes or make some new ones!
Maintenance of existing nest boxes is an essential seasonal chore. They should be built with doors or removable sections so that you can easily clear out the old nesting material inside once the young birds have fledged. These old nests can be full of parasites waiting for a fresh clutch of young birds to appear next spring. House Wrens even purposefully decorate their nests with spider egg sacs, possibly to deter some of these annoying parasites! While birds can and will build on top of an old nest, it’s ideal for the health of new nestlings to keep it clean instead of allowing a strata of dirt and droppings to grow beneath them.
Many birds are cavity nesters that build their nests inside enclosed spaces such as hollow trees. These birds, from owls to chickadees to even ducks, are quick to take advantage of man-made nest boxes. Common Goldeneyes are a great duck species to attract with a large box attached to a post or tree facing the water, anywhere from six to thirty feet off the ground. Meanwhile, non-cavity nesting birds like the American Robin prefer a simple shelf with a roof attached to a post or the side of a building, facing in any direction.
There are, however, some species that you will want to discourage from taking up residence in your nest boxes. European Starlings and House Sparrows are both common invasive species that take up valuable nesting real estate from native species, which often face population declines as a result. If you see either of these species using one of your own boxes, you can attempt to deter them by removing their nests as they start building.
Nesting birds are not always picky, and many will build inside any object that is roughly the size they’re most comfortable with, which can cause problems. Social media sites like Pinterest are filled with cute, quirky birdhouses built out of repurposed materials like old teapots. While these can be decorative and full of personality, they can also be lethal. A hot day could cook eggs or nestlings, and a cold day could very well freeze them. It’s much better to stick to trusty wooden designs that are both safe and bird-friendly. If you are looking to attract Common Goldeneyes, American Robins, Tree Swallows and more, you can check out the Cornell Lab of Ornithology’s “All About Birdhouses” at www.nestwatch.org for blueprints and tips!
Sadly, due to the ongoing pandemic, the LSLBO will continue to be closed to the public during the spring migration season.
By Bronwyn Robinson, LSLBO Assistant Bander