A steer skeleton lay in the dry creek bed. Tom extracted a tooth from its skull and handed it to me like a picked flower. Its roots were long and brown, so desiccated they looked almost wooden. Only its crown was any bit of white. I slipped the gift into my backpack — a souvenir of square V17.
Tom's wife, Ann, said that things had changed completely since the last time she and Tom were here in V17. "In the spring, this was neck-high grasses! We got lost, separated from each other a couple of times. We were tripped by the logs that were hidden and fell on our faces. It was difficult to find a true path; eventually you'd find that it was a false path. We practically had to hack our way through here with our bare hands. A machete would have come in handy." She lifted her binoculars. "There's a California towhee," she said, pointing the lenses at a place on the ground about 100 yards away. "They're around our house in La Mesa. They come right into the garage. The cats wish they could have them."
As Ann wrote in a small spiral-bound notebook, I found the towhee with my own binoculars. What I saw was a chubby, gray-brown, robin-sized bird with a rust-streaked breast, a conical beak, and a way of foraging that made me think it was annoyed. Using both its beak and feet, it hunted for seed in the short, dead grasses. Despite its vexed manner, I envied the bird its lack of distractions and its purposefulness. It would never think of spying on me.
But the Keenans have a purpose here too; they’re not just birding for idle pleasure. They’re collecting data for the San Diego County Bird Atlas. “Citizen science” is one name I’ve seen to describe projects that use volunteers who engage in fieldwork under the supervision of the professionals who recruit them. Tom’s background isn’t biology: he retired early, 15 years ago, from his job as an electrical engineer (or “double e,” as he says); at the same time, Ann left hers as a computer scientist. Together they started exploring things. In 1988, they took their first birding course from a local chapter of the Audubon Society. “As far as we’re concerned,” Tom told me, “birds entered the planet that year.”
V17, as it’s known on the bird-atlas grid of the county, is a three-by-three-mile square close to the border near Tecate. On our way to it we took a dirt road that became a washboard road. Our voices vibrated as we rode along in the Keenans’ 1999 black Mercedes SUV. The part of the square that we were on now was grazing land. We could see the herd in a distant pasture; later we would almost stumble into a stray herd member who was sitting as still as a big, black boulder under a live oak tree. Tom pointed out that all the oaks in the area were trimmed up to steer-mouth height and that no smaller ones grew underneath them: the steers had eaten the seedlings too. Meanwhile, Ann spotted lark sparrows feeding under one of those oaks and wrote in her notebook again.
The smell in the air was the sea at low tide. The Tecate and Cottonwood Creeks come together in V17, then flow into the Tijuana River. The land is owned by the San Diego County Water Authority — a rancher rents it — and the Keenans and I needed permission to be on it, along with a key to unlock the gate. They hadn’t bothered to put their official sign on the windshield: “Bird Atlas. Volunteers Conducting Bird Survey. A Project of the Biodiversity Research Center of the Californias of the San Diego Natural History Museum.” The Border Patrol had probably already seen us with our birding gear anyway. Their cars occasionally appeared on the cliffs above us, and their helicopters sometimes passed overhead.
The Keenans signed up for the bird-atlas project as soon as it began, on February 22, 1997. When the results of the five years of fieldwork are published by the museum, as a series of color-coded maps with detailed commentary, we will know exactly what birds were where — and when — and what they were doing during the five-year period that ended on February 28, 2002. A comparison of this fresh data with available historical data will reveal how distributions have changed over the past century. We’ll also know which birds are adapting to urbanization and “habitat fragmentation” — and which ones aren’t.
The project isn’t unique. Bird-atlas work has been conducted in Europe since the mid-1960s. In the United States, the first results of bird-atlas surveys were published by Vermont and Maryland in the 1970s. The California counties of Marin, Monterey, and Sonoma have published bird atlases recently. Fieldwork for the bird atlases of several other counties in the state is underway. And San Diego itself has had a forerunner to this current project; the results were published by the museum in 1984 as The Birds of San Diego County.
Philip Unitt, collection manager of the museum’s birds and mammals department, was the author of that earlier study and did most of the fieldwork for it himself. That wasn’t what he had intended to happen. “A group of us talked about doing an atlas in 1978,” he told me in his office one day. “But as time went on, the other people fell by the wayside until I was the only one left. We all realized an atlas was needed; the latest thing available was from the 1950s.”
Unitt’s reference is to the 1959 annotated list of birds in San Diego County compiled by James R. Sams and Ken Stott. Forty years earlier, Frank Stephens (1849–1937), a self-taught ornithologist, compiled the first list for the region. In 1924, Stephens became the San Diego Natural History Museum’s director; his collection of study skins formed the nucleus of the museum’s collection.