September brings migration to New Mexico
Migration is defined as the regular movement of birds between their breeding and wintering areas. Migration is seasonal and predictable. We think of the V-shaped formation of Canada geese as the epitome of migration, but of the more than 650 bird species that nest in North America more than half migrate.
Migration can be triggered by several factors, including changes in day length, changes in food availability and cooler temperatures. Genetic predisposition also is a factor.
Why do birds migrate? According to the Cornell Lab of Ornithology, “Birds migrate to move from areas of low or decreasing resources to areas of high or increasing resources. The two primary resources being sought are food and nesting locations. Birds that nest in the Northern Hemisphere tend to migrate northward in the spring to take advantage of burgeoning insect populations, budding plants and an abundance of nesting locations. As winter approaches and the availability of insects and other food drops, the birds move south again. Escaping the cold is a motivating factor but many species, including hummingbirds, can withstand freezing temperatures as long as an adequate supply of food is available.”
Some birds do not migrate but are permanent residents. They can find adequate food supplies year-round. A few of our permanent residents include canyon and spotted towhees; downy, ladderbacked and hairy woodpeckers; curvebilled thrashers; bushtits; house finches; Steller’s, pinyon and Woodhouse jays; and many more.
Some birds, like jays, nuthatches and chickadees, don’t really migrate but often move around a bit locally to find food or to nest. You could categorize some of these birds as short-distance migrators, even though the distance may be only a couple of miles. You may not see these birds for long stretches of time, so it might feel like they’ve been far away when most likely they’ve been hanging out all summer a little higher in the mountains for better nesting and food options. Now they’re knocking on your door again expecting a steady source of winter food and water.
Many of our long-distance migrators are heading to Central or South America for the winter. Some of them include hummingbirds, western tanagers, Bullock’s and Scott’s orioles, swallows and many warblers moving through right now. Some birds, like the lesser goldfinch, mostly disappear in the winter in much of Santa Fe, but they don’t go far and can be found just a little farther south in New Mexico.
Juncos are beginning to arrive to winter in our area. Some winters, we also have many robins spending the colder months with us. Most of these are robins from states to the north that have decided to winter in Santa Fe. Pine siskins and evening grosbeaks are irruptive species but tend to show up at area feeders as winter approaches.
Migration is complicated. Some species go far, some stay put and some move just a little. Some leave us, but others come for the winter. Whatever the case, there is a lot of bird activity happening right now. Be ready for a little different variation of backyard birds to begin to arrive for the winter or just looking for a snack as they move through on their way farther south. Keep your feeders full of high-quality bird food with lots of sunflower or sunflower chips and a little millet (juncos and migrating sparrows love millet!). Add a suet feeder to appeal to insect eaters like warblers, and keep your birdbath full and fresh. Make your backyard an oasis full of native grasses, flowers and shrubs, and don’t trim old seed heads. Nobody prunes the forest. An overgrown backyard provides more food options and better cover for birds.
In recent days, I’ve heard reports of yellow-headed blackbirds, red-shafted flickers, MacGillivray’s warblers, yellowrumped warblers, orange-crowned warblers, lots of Wilson’s warblers, blue-gray gnatcatchers, Canada geese, swallows, great blue herons and many, many more species of birds. Keep your eyes peeled!
Anne Schmauss is the co-owner of Wild Birds Unlimited in Santa Fe, and she loves to hear your bird stories. She is the author of For the Birds: A Month by Month Guide to Attracting Birds to Your Backyard and Birdhouses of the World.