Back Issue
September/October 2001

A Garden for Migratory Birds
by Christine Cook

The chilled blue currents of the sky swirl with swallows and robins. A thousand goodlucks all over the world! There is always a late afternoon in the late of summer when someone in my family slowly and softly whispers, “the light is changing.” A passing, a fleeting of things.

Is it this change in light that signals to migrating birds? What innate knowledge tells them it is time to go? What star maps might they follow? Which unseen magnetic field holds them to their course? The mystery of migration is slow to give up its answers.

Migrating songbirds in Connecticut fill the autumn air with a cheerful celebration of warbles, trills and whistles. Two locations where migratory birds gather in our state are Hammonassett State Park and Milford Point.

Different Forms of Migration
Some migrating birds will travel in huge concentrations assisted by the north wind on their backs. Occasionally 200,000 birds an hour will pass in a broad front. Others will make a solitary effort flying alone.

Some birds will make a complete migration, heading to southern Florida, Central or South America. Others like the American Goldfinch may fly only a couple of hundred miles in a partial migration. Irruptive migrators (who move south to secure a reliable food source) like Evening Grosbeaks may only move in particularly harsh years.

Scientists know that in some species the adults leave earlier than the young, imprinted with the experience of where to find cover, shelter, food and water. The young must travel by instinct. Songbirds can travel 200 miles a day but then must rest and refuel for three to five days.

A Change in Bird Metabolism
Bird’s lives are intimately connected to the changing seasons and the changing food sources on which they depend. Consider, for example, the Scarlet Tanager. As fall approaches, the male’s flamboyant spring plumage has changed to a softer drabber olive. He will start to stay up longer at night because that is when he will fly, avoiding predators.

Connecticut’s first autumnal frosts arrive in the northwest hills about September 25 and on the coast about October 26. With the frosts go many of the protein enriched insects the Scarlet Tanagers and other birds have been dining on and feeding their young.

The Tanager’s metabolism has changed to allow him to convert more of his food into fat, which is high in calories and provides the necessary energy to fuel his southward migration.

Autumn is burgeoning with berrying plants. Berries, because of their high caloric content that can be converted into fat, are excellent food sources for migrating birds.

Berrying Plants for Migratory Birds
Planting berrying shrubs and trees will bring these beautiful creatures into your yard and will help to enhance Connecticut’s environment by building more reserves and eventually increasing the bird population density.

To create a sanctuary build diversity into your design. Provide water, shelter and nesting sites. Include plants of different heights from canopy to groundcover. Give birds a place to perch and sing their hearts out! Make sure they have nest building material. Plant evergreens that will give protective cover from predators.

Elderberry (Sambucus canadensis) has berries that disappear in July — the Robins don’t even give them a chance to ripen. Twenty-eight different songbirds consume them, including Indigo Buntings and Gray-cheeked Thrushes. One of the earliest birds to arrive in the spring is the Rose-breasted Grosbeak. It is also one of the earliest to leave, rarely staying past November. Connecticut elderberries supply much of its fat for the first trek of its journey.

Highbush blueberry (Vaccinium corymbosum), decorated with bluish berries in late July and early August, feeds 22 different songbirds. The Hermit Thrush, considered by many to have the most beautiful voice, feasts on this plant. The Baltimore Oriole, one of the first to leave in mid August, will leave his post in the tops of trees eating caterpillars to dine on blueberries. If he happens along some blackberries (Rubus allegheniensis) he’ll consume them readily, too.

Spicebush (Lindera benzoin) has a berry enjoyed by vireos. In September you rarely ever see the red berries beneath the aromatic yellow leaves — they are eaten too fast. They are particularly sought out by the Wood Thrush who makes his exit between late August and mid October.

Carolina rose (Rosa carolina) has hips which ripen in late August and persist until late March. Thrushes and vireos love them. Our winter migrants rely on them when snow is on the ground.

The fruits of viburnums need to freeze before they sweeten and are sought out by some late lingering migrants. Arrowwood viburnum (Viburnum dentatum) has a bluish black drupe from early September to late November. Highbush cranberry (Viburnum trilobum) save their cinnabar-colored fruits until February, not only feeding the straggling Robins but some of Connecticut’s yearlong avian citizens. Include withe-rod (Viburnum cassinoides) with its pink, blue and black drupes.

Bayberries (Myrica pensylvanica) have an extraordinarily high fat content and hold their ripeness from September to May. Tree Swallows can stay farther north longer than any other swallow because of bayberry. The Scarlet Tanager’s diet is usually made up of insects but it will pop down for some bayberries while on its way south in mid October. It also has a penchant for the fuzzy fruit of sumacs. The late drifting Yellow-rumped Warbler is uncommon and local, breeding in the northwest hills. It can be widespread during migration. It dines on bayberries, dogwood and viburnum. Nutritious fatty seeds of grasses, sunflowers and goldenrod round out its diet.

Eastern red cedar (Juniperus virginiana) provides both shelter and sustenance. Plant a male and female and watch a flock of Cedar Waxwings descend and demolish its horde of pale blue cones.

Hackberry (Celtis occidentalis) fruits from September through October with many fruits persisting into February. It is an incredibly important foodsource. orioles, Robins and the uncommon Fox Sparrow love the fruit.

The flame-colored foliage of virginia creeper (Parthenocissus quinquefolia) and poison ivy (Toxicodendron radicans) alert birds to their fat packed fruit. They are depleted quickly by a multitude of bluebirds, finches, flickers, sparrows, thrashers and vireos. Dare to leave a cache of poison ivy somewhere on your property!

Hollies attract Brown Thrashers, Hermit Thrushes and bluebirds. Both winterberry (Ilex verticillata) and inkberry (Ilex glabra) have abundant berries.
Dogwoods set a true banquet. There are so many kinds in our area. The fruit is high in calories and provides food for 27 birds. Red-eyed Vireos, incredible woodland songsters, relish them.

Many of our bird populations are declining because of development. We can choose to support them. Encourage them to visit by planting some tempting berrying trees and shrubs. Watch these elusive creatures dart and retreat amidst fall’s colorful leaves eating succulent fruit. Listen to them sing their effervescent songs before they flee too fast.

Christine Cook, the owner of Mossaics in Easton, CT, designs eco-friendly landscapes including moss gardens and native plantings. She also writes and lectures.