A Hummingbird’s Niche

What hovers like a butterfly, pollinates like a bee, and flashes brilliant, iridescent streaks of color in our gardens? Hummingbirds, of course.

Since hummingbirds are found only in the Western Hemisphere, early European explorers sometimes thought hummers were half bee, half bird. Their skins were shipped to Europe by the thousands to ornament everything from royal robes to ladies´ hats.

Today a hummingbird’s challenges are quite different. As humanity spreads to envelop wild lands, the hummingbird’s breeding and wintering ranges and migration routes are subject to logging and development. Hummingbirds are fortunate–people like them for their beauty and spunk, and unlike many wild creatures they are sometimes able to adapt to suburban gardens.

Nonetheless, four North American hummingbird species are on the Audubon Society´s Watch List of declining and/or rare birds–Costa´s, Calliope, and Allen´s are occasionally seen in our Foothills, as is the rusty-brown Rufous which has declined an alarming 58 per-cent in the last forty years. The birds´ territories also are in flux, often moving into our gardens as their original habitat shrinks. This summer, for the first time, my garden is home to an apparent breeding population of Black-Chinned hummers, and during Audubon´s February Bird Count several amethyst-crowned Costa´s adorned my feeder. And yes, fewer Rufous.

The West, including our Foothills, is dominated by the rosy-red helmeted Anna´s hummingbird. The Audubon Hummingbird Project in Tucson focuses on the effect of feeders and availability of hummingbird plants on the numbers and species of birds. Perhaps this project will shed light on which birds survive and where. Competition from dominant species likely plays a role.

THE FOOD FACTOR: Hummingbirds are a fine example of some interconnections within a wildlife habitat (including our domesticated gardens). Following a diminishing nectar trail of manzanita and other native flowers, hummers migrate north each spring. Native blossoms, small insects, and now more commonly nectar feeders, sustain them until warmer weather brings more flowers. Hummers rely also on sugar and small insects from sapsucker wells. (Sapsuckers are woodpeckers that drill lines of holes or “wells” in the bark of living trees and shrubs and then forage for sap and small insects that fill the holes.)

Upon arrival to their destination, female hummers soon begin building their walnut-sized nests from bits of plant down, mosses, spent flowers, and other garden materials. Spider webs may help hold the nests to branches. All hummers must draw nectar from hundreds, even thousands of blossoms each day and consume innumerable tiny insects to sustain energy for their revved-up metabolism and for the females to lay and incubate their miniscule eggs. The female feeds her hatchlings with more nectar and tiny insects.

HUMMINGBIRDS AS POLLINATORS: Native pollinators are making headlines these days as honeybees (European in origin) decline. While feeding, hummers pollinate by thrusting their bills deep into a flower, collecting pollen on their bill and feathers. At each subsequent flower, the hummer leaves a little pollen and picks up some new, spreading pollen from flower to flower. The seeds and fruits resulting from their endeavors later feed other birds and mammals which then distribute the seeds to help create the next plant generation.

With their long, tubular bills, unique hovering skills, and the ability to fly backward and even upside-down, hummers have unsurpassed ability to pollinate plants with long, tubular blossoms. The shape of such blossoms makes it difficult for some bees and other larger pollinators to reach the pollen deep within the flower. Many scientists believe our native tubular-flowered Penstemons, sages (Salvias), columbines, and certain other native plants, evolved together with hummers, enhancing each others´ survival.

Sphinx moths, sometimes called hummingbird moths, are active at dusk or nighttime while gathering nectar from and pollinating most of the same flowers as hummingbirds.

PLANTS VS. FEEDERS: Flowers are much easier to care for in the long run; you don´t have to scrub them or worry about replenishing the solution and keeping it fresh, and a feeder never perfumes the evening air.

Flowers draw a host of insects and spiders that numerous creatures need for survival, including birds, mammals, and amphibians. Flowers also support bees, hover flies, and a host of other beneficial insects that help pollinate gardens and crops.

Many hummingbird blossoms also attract butterflies-chaste tree (Vitex) and butterfly bush (Buddleia) are two examples. And, each spring I find mourning cloak butterfly caterpillars on my Penstemons. Even orioles sip nectar from red hot poker flowers, another hummingbird favorite.

A feeder on the other hand supports only hummingbirds, but combined with flowers a feeder will likely draw more hummers of perhaps several different species. Replenish your feeder regularly, including through the winter for the birds that do not migrate. Dirty feeders are the source of a fungus infection that causes a bird´s tongue to swell; mother birds can pass it to their babies making it impossible for them to eat.

Eliminate the red food coloring since the birds will find your feeder without it. With their tiny bodies and great need for calories, a hummer can consume a dose of food coloring many times that generally recognized as safe for humans. To protect your garden´s wild creatures use pesticides of all kinds very sparingly–or better yet, not at all.

Your garden´s wildlife will be appreciative if you plant California natives whenever possible. Fall is the best planting time for most natives. Area nurseries and our local California Native Plant Society´s (CNPS) upcoming fall sale are excellent sources for natives and advice regarding their care. Our CNPS chapter offers a list of native hummingbird plants as does the Santa Clara chapter, www-leland.stanford.edu/~rawlings/hummer.htm, though you will need to edit this latter list for plants suitable for our growing conditions.

For more information regarding pollinators including hummingbirds, visit http://www.fws.gov/pollinators/Index.html This site also offers pollinator teaching tools for educators.

Master Gardener Vera Strader´s favorite hummingbird plant is California fuchsia (formerly Zauschneria, now Epilobium) that blooms flaming orange in her Sonora garden from summer through fall.