SIERRA VISTA, Ariz. -- ''You want a hummingbird taco?" Wrapped tightly in a net bag, the tiny bird looks like a fancy hors d'oeuvre at a celebrity cocktail party.
But this isn't a trendy Hollywood club, it's Ramsey Canyon Preserve, a Nature Conservancy reserve in southeast Arizona. Instead of sipping martinis, we watch as volunteers catch and band the delicate birds. From April to September, the tiny wonders are star attractions.
Dozens of hummingbirds, six species so far today, zoom around feeders that hang behind the preserve visitors center. A round net, like mosquito netting over a bed, crowns each feeder. Watchers pull long strings that drop the hoods over the feeders when a bird zips in for a sip. The wait is never long.
''We've banded 23 since 8 o'clock this morning," Susan Wethington, project leader for the Hummingbird Monitoring Network, tells us as she measures the bird in the bag. ''We band for two hours every other Wednesday during the hummingbird season."
The coalition of volunteers coordinates with universities, preserves, and parks to monitor hummingbirds that migrate from their winter homes in Mexico to destinations as far north as Canada.
Wethington carefully places the taco bird, a male black-chinned hummingbird, on the scales. ''He weighs 2.7 grams," she says. Then she places a penny on the scale. It weighs 2.5 grams. The thought of a bird that weighs little more than a penny migrating 2,000 miles boggles my mind. It also mystifies biologists.
''We don't know much about the migration routes or the important breeding locations for many of the hummer species," Wethington says. ''By banding the birds, we can tell if the populations are increasing or decreasing and develop conservation programs." The group operates 14 banding stations in Arizona, six in California, and five in British Columbia.
Wethington carefully slips a numbered band on the leg of the emerald-colored bird. ''So far today, we've had four returns from last year," she says. She holds up a feeder and the hummer eagerly pokes its slender bill into the feeding hole for a long drink.
''We know he's not too stressed if he feeds before we release him," she says. ''Cup your hands and hold them out." She gently slips the bird out of its straightjacket and places it in my hands. It sits motionless for a second, then, in a blur, vanishes. I feel like a magician, but the magic is in the bird, not the disappearing act.
Once known mainly as the remote, dusty home of an Army base, Fort Huachuca, Sierra Vista now is considered one of the nation's leading ecotourism destinations. Just as whale watchers head for the oceans and skiers the mountains, wildlife lovers go to southeast Arizona to see hummingbirds and rare Mexican birds that wander north into the Huachuca Mountains. Stretching from Mexico to the southern tip of the Rockies, the 9,600-foot-high Huachucas provide a tropic-to-temperate-zone corridor for plant and animal species.
''The Huachucas have the greatest diversity of hummingbirds in North America," Wethington says. ''The numbers drop off going east and west. Of the 18 species north of Mexico, 15 occur in southeast Arizona. In contrast, only one, the ruby-throated, breeds east of the Mississippi River."
Hummingbirds aren't the only birds attracted to the mountains. The lush canyons and isolated peaks form refuges surrounded by desert. The red-faced warbler, red crossbill, and other rare mountain species live in the high country, while hummingbirds favor medium elevations. In the Ramsey Canyon visitors center parking lot, a volunteer sets up a spotting scope and focuses on a golden eagle nest on a rocky outcrop. The chick's head peers above the nest rim as it waits for a parent to return.
Ramsey Canyon and three other scenic canyons drop out of the Huachucas within 10 miles of Sierra Vista. The protected canyons connect the desert grasslands with the evergreen forests of the high country. The diversity of blooming plants from mountain to desert creates a hummingbird heaven. The Ramsey Canyon Inn Bed & Breakfast and Housekeeping Suites, and two more inns nestled in other canyons attract hummers to their feeders and nature watchers to their doorsteps.
At Ash Canyon Bed & Breakfast about 15 visitors, some from England, sit in the shade and watch a mesquite tree with six numbered feeders. A bird flies in and hovers. ''Male broad-billed at number three," someone says. Conversation halts and a dozen binoculars snap into place.
Mary Jo Ballator moved to Ash Canyon six years ago from the San Francisco area. ''We get a good number of rare hummingbirds, which made me realize what a special place this is," she says. In 2002, she opened the B&B. She rents only one room, but last year more than 2,000 people visited the public viewing area to see her feathered friends.
''During the Southwest Wings bird festival last August, 1,000 people showed up to see the plain-capped starthroat. We've had both the Berylline and Lucifer hummingbirds for two years in a row. Stick around until 6:15, that's when the Lucifer shows up."
Miller's Canyon has a well-earned reputation for premier hummingbird viewing. Beatty's Guest Ranch, with six cabins, holds the North American record for most species of hummers seen in one day. Last June 30, viewers spotted 14 of the 15 species recorded in the area. By mid-August, when hummingbird numbers peak, birds at the viewing stations drink 45 quarts of sugar water per day from as many as 62 feeders. That equates to more than 4,000 hummingbirds.
Sherry Williamson and Tom Wood, who founded the Southeast Arizona Bird Observatory, lead tours in Miller's Canyon.
''The journey to southeast Arizona is an ecotour pilgrimage for serious bird-watchers," Williamson says. ''Beatty's Guest Ranch offers the best hummingbird viewing in the United States."
Trails lead up Miller's Canyon and Carr Canyon into the Coronado National Forest, where visitors often see eared and elegant trogons, whiskered screech owls, and sometimes rare Mexican species such as the Aztec thrush and flame-colored tanager. Monthly bird walks begin at the national forest's visitors center in Carr Canyon.
The streams that pour through the Huachuca Mountains all feed into the San Pedro River, one of the last untamed waterways in the West. The Upper San Pedro River watershed, the collection of habitats that stretch from the greenbelt along the river to the mountain peaks, contains five distinct ecosystems within five miles.
The San Pedro Riparian National Conservation Area preserves 40 miles of the river greenbelt. More than 30 miles of trails parallel the river. The San Pedro House visitors center, 7 miles east of Sierra Vista, offers another chance to get close looks at hummingbirds. The bird observatory bands the tiny travelers weekly April through July.
Dutch Nagel, a volunteer formerly from Pennsylvania, meets us at the visitors center. We walk through a parched field to a band of cottonwood trees along the river. Though the knee-deep flow would count as a creek in most areas, it's a green ribbon of life in the desert.
''The San Pedro is the only north-south river between the Colorado River and Rio Grande," Nagel tells us. ''During the migration seasons from April to May, and August to September, thousands of birds follow the river. More than 400 species, half of all that occur between the Mexican border and Greenland, either nest or migrate along the San Pedro."
Arizona earns its reputation as the nation's hot spot, not just for summer temperatures, but also for watchable wildlife. With lush canyons, sky-island mountain peaks, and a desert river corridor, southeast Arizona rates as one of the most ecologically diverse regions in North America.
George Oxford Miller is a freelance writer in New Jersey.