A crow was rifling through my plastic recycling this morning and pulled a tangle of bags clear of my carefully stuffed bin. When I went to tidy up, the crow cawed loudly, annoyed to be disturbed from its important work of finding nest material. May is bird nesting season and, for many of our neighbourhood species, it is time to find space in our crowded world to lay eggs and bring up young ones.
With natural landscapes disappearing from the lower mainland, finding a good nesting site can be challenging. Unlike many woodpeckers, the northern flicker will reuse holes from previous seasons, but this year our local flicker distained last year’s nest in a decaying snag, and hammered a significant hole in our neighbour’s siding. Barn swallows are also drawn to buildings and their mud nests are often built under house eaves, a habit that some people dislike. If you have nesting swallows, please try and tolerate them. Swallow populations, like those of many insect-eating birds, are in steep decline, and they are now on the endangered species list. Delta still has a fairly healthy local population around the farmland, where local landowners allow them to use barns and sheds. Not only swallows benefit from farms. Only a few barn owls live in Canada, and Delta’s farms provide excellent nest sites and hunting habitat for them in fields and hedgerows.
Some birds build nests in trees and bushes, in holes or among the branches. Many suburban gardens lack the density of vegetation necessary to support nesting birds, so homeowners miss out on the beautiful song of the American robin on spring mornings. Thrushes, finches, dark-eyed juncos and black-headed grosbeaks need thick foliage and tangled shrubberies to provide suitable nesting sites, hidden from cats, raccoons and hawks. Bushtits that build woven, hanging nests need a steady supply of aphids to feed their young, so like hummingbirds are attracted to flower gardens. Natural gardens are more likely to have birds. Chickadees often take to nest boxes and have large broods, so it is easy to provide a home for these little birds.
Other birds nest right on the ground, such as the northern harrier, killdeer, and savannah sparrow, three species characteristic of the Boundary Bay marshes. Here they face the hazard of other animals stealing their eggs or eating their young. Please keep dogs on a leash when walking the dyke, to avoid disturbing nesting birds.
This article first appeared in the Delta Optimist newspaper.