July 15, 2010
Oases for Wildlife
Animal-friendly ponds transform ordinary backyards into vibrant mini-ecosystems
by Ruthanne Johnson
Tom Gatz’s yard in Phoenix, Ariz., bustles with the comings and goings of wild visitors. Birds nest in the mesquite tree and cactus plants, carpenter bees burrow into dried agave stalks, geckos dart behind rocks, and the occasional hawk swoops in to grab a meal. And then there are the unique Couch’s spadefoot toads, who bleat like sheep as they emerge from their underground burrows once a year, after summer rains have softened the scorched earth.
The desert terrain seems an unlikely place for such a rich community. But since Gatz replaced a manicured lawn with native plants and an L-shaped pond, he’s counted among the visitors to his yard seven mammalian species, eight species of reptiles and amphibians, six dragonfly species, and 73 bird species.
Building the pond took 10 days of backbreaking excavation with a pickaxe, but the retired wildlife biologist viewed the work as a labor of love. For homeowners like him, creating and maintaining a pond is about more than aesthetics; it’s a way to nurture wildlife and perhaps help compensate for human activities that have destroyed wetlands and depleted natural water sources.
“In reality, most of our created and restored wetlands start off as ponds,” says Tom Dahl, “Then vegetation fills in around the edges and an ecological succession starts to take hold.”
Gatz notes that rivers in his area once served as a kind of highway for migrating birds who aren’t adapted to desert living. But many of the rivers have been dammed and are dry at least part of the year, meaning that “instead of having a ribbon of green, [the birds] really depend on islands of habitat. They have to hopscotch across the desert in the spring and fall.” Collectively, he says, backyard ponds can make a difference for these animals—“like a string of pearls.”
Wetlands have been in decline nationwide, depleted mainly by agriculture, poor forestry practices, development, and dam construction. The lower 48 states in the U.S. once contained more than 220 million acres of wetland habitat; today, only about half that amount remains, says Tom Dahl, senior scientist for wetland status and trends with the U.S. Fish and Wildlife Service.
Even with recent gains due to restoration and conservation projects, the net loss remains substantial. Dahl believes that water features can at the very least provide habitat in wetland-depleted areas. “In reality, most of our created and restored wetlands start off as ponds,” he says. “Then vegetation fills in around the edges and an ecological succession starts to take hold.”
In Minneapolis, Minn., Oralee Kirk and her husband, Timm Weiss, have seen nature’s pageantry unfold over the last 30 years while transforming their suburban yard into a north woods landscape. They have replaced grass, petunias, and pansies with native plantings like wild ginger, trillium, bloodroot, and Solomon’s seal, as well as brush piles, pine needle mulch, and— the jewel of the property—a wildlife pond.
Since the metamorphosis, the couple has received visits from deer, wild turkeys, foxes, rabbits, and a plethora of birds and butterflies. Kirk has even observed a hawk bathing in the sandy shallows along the shoreline: “It takes a bath like I’ve seen robins do. It walks in one foot at a time, it steps and then looks around, steps and looks around … maybe a hundred times before it will dip its head in the water and flap its wings.”
Animals in the vicinity of wildlife ponds don’t make themselves at home just in the water. At the nonprofit Desert Botanical Garden in Phoenix, birds roost in trees on the edge of the 50-by-30-foot pond, making a feast of the desert hackberry, and rabbits, roadrunners, and lizards all come to visit, says horticulturalist Ray Leimkuehler. “If the animals don’t use the water directly,” he says, “they definitely utilize the vegetation planted nearby.”
The pond also beckons insects who provide food for the birds and other animals—and endless fascination for the garden’s staff and visitors. Bees climb down cattail blades to collect water, and they land on splotches of algae where they can take a sip before buzzing away, Leimkuehler notes. Dragonflies lay their eggs while skipping across the surface; the eggs settle to the mucky bottom where they hatch into nymphs, molting several times before climbing out of the water to become adults.
Wildlife lovers don’t need a big space to attract activity, says pond expert Brad Kerr; even a 5,000-square-foot urban lot has room for a 5-by-10-foot pond. As senior fishery biologist at Spring Creek Aquatic Concepts, an Oregon company that builds water features across North America, Kerr can attest to the possibilities of small spaces. On his parents’ deck in Portland, Ore., he built a small fountain and surrounded it with Indian paintbrush, forget-me-not, shooting star, and Jacob’s ladder. “It looks like a little miniature Columbia Gorge,” he says. “It’s naturally beautiful and the birds are all over it.” Avian visitors even build nests using material from a moss meadow Kerr planted nearby.
Well-filtered ponds with pumps to prevent water from stagnating don’t necessarily require a lot of maintenance—or chemicals to keep them clean. Leimkuehler rakes algae from the surface periodically, while Gatz vacuums muck from the bottom once or twice a year and uses it to fertilize his plants. He also cleans a skimmer of leaves and debris every week, and once a year he rinses a biological filter that breaks down animal waste.
As he and other backyard ponders have discovered, nature provides rich rewards for these efforts. From an open dining room window, Gatz and his wife can enjoy “surround sound without a stereo system.” They listen to the cascading waterfall, watch birds take refreshing sips, and spy colorful dragonflies clinging to the lilies planted along the shoreline. “Just sitting out here on hot summer days is kind of cooling itself,” he says. “It touches all of the senses—sight, sound, smells.”
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