Wildflower is published quarterly by the Wildflower Center. Its content is national in scope with articles about the conservation and use of native plants as well as news from the Wildflower Center. A subscription is provided to Wildflower Center members as a benefit of membership.
Hum's The Word by Roddy Scheer - Spring 2003
Thousands of landowners across the United States take great pleasure in turning residential gardens and backyards into suitable habitats for hummingbirds. When Jerry and Judith Paul moved into the log cabin they built in California's Monterey County, barley fields and oak woodland covered their new property, and wildlife was sparse.
The following spring, California Buckeye (Aesculus californica), a plant native to the central California coastal region, started to bloom near the cabin. The Pauls soon noticed lots of busy hummingbirds hovering around the property.
Eager to attract more hummingbirds, the Paul family decided to hang hummingbird feeders over the back door. "Within a day, the feeder had a hummer at every port," says Jerry Paul. "We added another feeder, and then another, until we had five 1-quart feeders hanging around the porch that surrounds two sides of our house. Within a week, we had 50 to 100 hummers feeding from those feeders, which we had to fill twice a day."
However, when spring turned to summer the Pauls realized their feeders were merely a stopover for hummingbirds on their migration path. That's when the Pauls augmented the existing California Buckeye with other native plants to attract more hummingbirds and hopefully keep them around for a longer part of the year. Their plan worked.
"As the native plants started to mature and flower, the hummers established territories, and some now stay all year," Jerry Paul reports. The Pauls learned that while feeders filled with sugar water or nectar-producing, non-native plants can attract hummingbirds, only a variety of native plants that flower successively can keep the birds coming back.
Although initially the Pauls saw hundreds of hummingbirds, once the feeders were gone and the plants in place the numbers leveled off and those birds - like Anna's hummingbirds (Calypte anna) - that naturally overwinter (meaning to remain during the colder months) established territories and stayed longer.
Discovering Nature's Jewels. Early Spanish explorers who had never seen the iridescent hovering birds before - all 300+ species of hummingbirds are endemic to the Western Hemisphere - called them joyas voladores, the "flying jewels." Indeed, hummingbirds' brightly colored and almost metallic appearance, combined with their ability to hover by rotating their wings in opposite directions as fast as 80 beats per second, make them a pleasure to watch.
The hummingbird also carved out a unique ecological niche for itself by co-evolving with the nectar-producing plants that serve as its food source. "Among the plant life native to [North America], about 150 plants have been determined to have special characteristics that evolved specifically to take advantage of hummingbird feeding," says naturalist Kim Long, author of "Hummingbirds: A Wildlife Handbook."
Every day, these birds consume almost their full body weight in flower nectar and insects. Insects provide the fats and proteins necessary to maintain proper nutritional balance, while flower nectar consists of water combined with natural sugars like sucrose, glucose, and fructose. As the hummingbird probes the flower's tube in search of nectar, its head picks up pollen that the bird unwittingly transfers to other flowers. Each hummingbird visits between 400 and 1,000 plants each day to obtain the 6,000 to 12,000 calories it needs.
Natives Give Refuge. The health of the hummingbirds mirrors the health of the environment. Today, hummingbirds thrive in most parts of North America, but their future is uncertain as native habitats succumb to highways, condos, and shopping malls. The destruction of indigenous flowering food sources threatens the long-term health of hummingbirds and thus represents a challenge for landowners to make their property more attractive to wildlife.
As the Paul family learned, North American hummingbirds are typically migratory, making them tricky to entice for extended stays. The hummingbirds follow long-established routes based on the flowering schedules of native plants, summering as far north as Alaska and wintering throughout Latin America. According to Long, 15 different hummingbird species spend several months each year migrating through the United States, while seven additional species are frequently sighted visitors. A handful of hummingbird species, like the Anna's hummingbirds, overwinter in the United States.
Wildlife enthusiasts make the most of opportunities to provide attractive residential habitats for both overwintering and migrating hummingbirds through native plantings.
University of Tennessee Biologist David Aborn favors native plants as hummingbird attractors for evolutionary reasons. "Anytime you can create a natural situation it will be better for the organism because you are less likely to have an influence on that species' biology," he explains.
Along these lines, Aborn warns that the injudicious use of feeders can "fool" some hummingbirds into sticking around beyond native flower blooms and may interrupt the migration patterns that are key to the long-term survival of many hummingbird species.
Beyond their appeal to hummingbirds, native plants benefit regional ecosystems and reduce maintenance costs because they are adapted to certain soil, moisture, pest-, and weather conditions. They require little or no fertilizer and also reduce the need for herbicides and pesticides that kill the insects hummingbirds need for protein and that are harmful to hummingbirds when ingested.