The pollinated and fertilized white flowers of Red Elderberry (Sambucus racemosa) have recently developed into the red fruit for which this plant is named. Many people are familiar with its relative, Common Elderberry (S. canadensis), which produces dark purple fruit that is used to make jams, jellies, pies and elderberry wine. While Red Elderberry fruit can be used to make all of these, its raw berries are toxic. Red Elderberry’s popularity is greatest with pollinators, birds and four-footed mammals.
The cyanide-producing toxins in its flowers, (raw) fruit, stems, bark, leaves and roots do not seem to discourage wildlife’s attraction to Red Elderberry. The odor of its flowers, its nectar, and its highly nutritious pollen attract many ants, bees, wasps and flies. At least 50 species of songbirds eat the bright red fruits, including red-eyed vireos, ruffed grouse, song sparrows, gray catbirds, brown thrashers, and thrushes. Squirrels, mice, raccoons, and black bears also eat the fruit. Porcupines, mice and snowshoe hares eat the buds and bark in winter. The foliage is usually avoided by herbivores, although white-tailed deer and moose browse on it occasionally.
There are many birds, such as waxwings, that have a frugivorous (strictly fruit-eating) diet. The only time they usually expand their diet to include insects is during the breeding season, when growing hatchlings require high amounts of protein for proper development. Others, such as orioles, show a marked preference for fruit but also eat significant quantities of other foods. All of these birds play an important role by spreading fruit seeds to distant areas either by caching food or distributing the seeds through their droppings.
Bird lovers often put out seed to lure birds in for a closer look (a practice discouraged during the summer in black bear country), but there is an equally effective magnet for some species, and that is fruit. (Due to the high sugar content, little nutrition and potential bacteria growth in jelly, it may be best to provide fruit over jelly.) Grapes often attract Northern Mockingbirds, Eastern Bluebirds, Cedar Waxwings, Gray Catbirds, Scarlet Tanagers, Rose-breasted Grosbeaks, House Finches and American Robins. Raisins and currants (soaked in water overnight) appeal to Northern Mockingbirds, Gray Catbirds, Eastern Bluebirds, Cedar Waxwings and Eastern Towhees. Species that find orange halves hard to resist include Red-bellied Woodpeckers, Northern Mockingbirds, Brown Thrashers, Baltimore Orioles, Scarlet Tanagers, Gray Catbirds and Rose-breasted Grosbeaks. (Photo: Gray Catbird (left), female Red-bellied Woodpecker (middle) and female Baltimore Oriole (right) enjoying breakfast at The House On The Hill Bed & Breakfast, Greenfield, MA.)
Some of the most prolific flowering shrubs in the Northeast are dogwoods. In the spring, their flowers attract attention and at this time of year their colorful fruit stands out. There are many species of dogwood, two of which are Red-osier Dogwood (Cornus sericea) and Silky Dogwood (Cornus amomum). These two shrubs can be hard to tell apart, as they both have white flowers, red stems and similar foliage. In the fall, however, the color of their fruit differs, as does their pith, or central stem tissue. The mature berries of Red-osier Dogwood are dull white and its pith is also white. Silky Dogwood’s blue berries have white blotches, and its stem and branches have a salmon-colored pith.
The fruit of these dogwoods and others is an extremely important source of food for many migrating songbirds, as well as resident birds. Wood ducks, Northern Cardinals, Eastern Bluebirds, Gray Catbirds, Purple Finches, Evening Grosbeaks, American Robins, Yellow-bellied Sapsuckers, Wood and Hermit Thrushes, Red-eyed and Warbling Vireos, Cedar Waxwings and Downy Woodpeckers all consume dogwood berries.
Gray catbirds begin their nocturnal migration to wintering grounds in late August and early September. The last of the stragglers are now passing through northern New England. Catbirds winter from the southern New England coast south to Panama, with concentrations on the U.S. Gulf coast and the Yucatan Peninsula. Those individuals that winter in the Yucatan Peninsula and Central America cross the Gulf of Mexico, and in order to do so they put on so much fat (during fall migration their mass may increase to 150% of lean body mass) that it approaches the upper limit of what flight allows.