Even before spring officially arrives, the sweet coos of mourning doves and the songs of house wrens and common yellowthroat warblers can be heard early in the morning through windows left cracked open the night before. Those first musical trills of prodigal birds, likely exhausted from their migration from as far south as Central and South America, can make us feel simultaneously relaxed and energized — and elated that a new season is within reach.
But spring isn’t the only time of year we need think about birds. Although hundreds of bird species head to warmer climates in the fall, others, black-capped chickadees, cardinals and woodpeckers among them, remain to tough out the winter, trading the perils of migration for the hazards of harsh weather and the food scarcity that accompanies it.
As our perennials go dormant and deciduous trees shed their leaves, fruits and seeds disappear with them, as do insects, most of which either die or hibernate. But birds can adapt; some insect-eaters pivot to a berry-centric diet, and some grow extra feathers, then puff them out — essentially making their own parkas, trapping air between layers to create bubbles of warmth. Still, they can use our help.
Carefully choosing native plants for your garden will beef up the food chain, feeding insects that birds, in turn, will use to feed their chicks come spring. This is important because our native insects and wildlife evolved alongside our native plants, adopting them as diet staples. Many exotic plants, on the other hand, aren’t even recognized as food by North American insects and caterpillars, according to research published by University of Delaware entomologist and author Doug Tallamy.
What to choose
Our native oak trees, for example, support more than 500 species of insects, including butterflies and moths, he asserted in his 2007 book, “Bringing Nature Home: How Native Plants Sustain Wildlife in Our Gardens,” which has since become the bible of the native plant movement. When in their caterpillar stage, those butterflies and moths are the primary food source for birds. The nonnative ginkgo tree from China, on the other hand, while often prized for being “pest free,” supports fewer than five.
Tallamy, who reminds us that baby birds do not eat seeds but rely solely on insects, has found that one nestful of chickadee hatchlings needs to consume 6,000 to 9,000 caterpillars en route to maturity. Without native plants that support those insects, we simply would not have birds.
In addition to trees and perennials, consider including evergreen shrubs and ground covers in your landscape; they’ll provide shelter and cover. And bushes that retain fruit or nuts over winter offer food, as well as something nice to look at when all else is barren.