By Edie Parnum
Whenever my family goes on long automobile trips, we never have to worry about finding places to eat and sleep. However, songbirds traveling through southeastern Pennsylvania in the fall undoubtedly have a hard time. Much of our area is paved over and built up. Even the residential suburbs are rather unproductive landscapes with mostly grass and scattered trees. Migrant songbirds fly at night; and when dawn comes, the weary, hungry birds must find immediate shelter and food if they are to survive and continue their journey.
We tend to assume that migrants can depend on the local parks and other preserved areas. However, these may lack the desirable native understory plants because of browsing by deer. Invasive alien plants like Multiflora Rose and Japanese Honeysuckle have filled this vacuum under the canopy trees. Birds will use these plants for shelter and even for food, but the fruits are less likely to satisfy their urgent nutritional requirements.
Scientists tell us that even small patches of suitable habitat may provide for the needs of migrating birds. A private property can supply native shrubs, understory trees, and vines with fruits that ripen just at the right time in the late summer and fall. At this season most of these plants have red foliage or brightly colored berries to attract the passing birds.
Although thrushes, grosbeaks, waxwings, orioles, tanagers, and towhees are primarily insect eaters during the nesting season, they switch to a diet of fruit in the late summer and fall. Just like athletes who load up on carbohydrates for a big game, the birds eat fruits ravenously to give them energy and fat for their strenuous journeys. They actually need to add fifteen to fifty percent to their total body weight in preparation for migration.
In my own yard I have been adding woody plants that produce fall berries. Now that many are mature enough to bear fruits, I’m seeing many birds eating hungrily and fattening up for the journey ahead. The elderberries are the first to be eaten. By late summer the local robins and catbirds start devouring them even before they are fully ripe. Before long they are eating the fruits of the blueberries, viburnums, dogwoods, and hollies along with the passing towhees, orioles, jays, thrushes, and waxwings. I’ve even seen a Black-throated Blue Warbler, which is usually strictly insectivorous, eating blueberries. One year a Hermit Thrush stayed for most of the winter eating the holly berries that are plentiful in my yard and nearby. Other trees, shrubs, and vines I have planted like Spicebush, Sassafras, Black Gum, Common Hackberry, Red Chokeberry, and Virginia Creeper are still young. One day these, too, will provide food and shelter for the migrants.
There are other things I am doing my yard for the fall migrants. Because some birds switch from insects to seeds in the fall, I let the native perennials like rudbeckias, coreopses, sunflowers, goldenrods, and clump-forming grasses go to seed. I have seen passing sparrows like Chipping, Field, Fox, White-throated, and White-crowned take advantage of the bounty. The Trumpet Honeysuckle continues to flower into the fall for the passing hummingbirds. For the warblers, wrens, and other birds that are primarily insect eaters, the native trees, shrubs, and grasses in my yard are hosts to the native insects as well.
We nature lovers worry about bird conservation but often assume that there is little we can do except give money to organizations that preserve land. Certainly, in all likelihood, we cannot provide nesting habitat for any endangered birds in our yards. However, migration is difficult, so possibly we can make a difference by growing the plants that fall migrants need and love. And perhaps we can encourage our neighbors to do the same.