It was a particularly gray and dreary day when the band of binocular-bearing folks trickled--usually in pairs--into Escondido's Kit Carson Park.
Many had been out since before dawn, counting birds. Now they have gathered to share chili and what they've seen.
Ken Weaver, president of the Palomar Audubon Society, calls out names of species. The birders who have seen the species call out their sightings. Almost everyone saw the flock of about 500 Canadian geese that took to wing somewhere near the Wild Animal Park.
The count of the most interesting birds encountered that day, which included the long-billed curlew, the Townsend's solitaire and the bald eagle, was saved until last.
This count on the last Saturday of the year covered the San Paqual Valley, from Escondido to Ramona. It was just one of many Christmas bird counts, which are sponsored by the National Audubon Society and occur across the country during a two-week period in December.
The final results of the counts will not be available until February or March, although it's estimated that about 200 species of birds were sighted in North County. The results will be passed on to the National Audubon Society for publication.
San Diego birders hope to be among the top in the nation in the number of species they counted.
That goal is not far-fetched. San Diego County has the distinction of playing host to more species of birds than any other county in all of North America.
The reason for the distinction lies in the county's richly varied habitat, which attracts both visiting and resident birds. That same varied habitat also lures humans who build in the same places the birds prefer--on bluffs overlooking the Pacific and in river valleys.
Although mourning doves and killdeers find the changes wrought by humans to be quite agreeable, others, like blue-gray gnatcatchers, find their habitat increasingly inhospitable. While the fate of a 4-inch, fidgety bird may seem trivial, wildlife experts warn that the gnatcatcher's health mirrors the health of entire ecosystems.
"Birds are sensitive indicators of environmental changes, and information about birds is important in evaluating the biological resources of an area," says Philip Unitt, curatorial assistant in the Department of Birds and Mammals at the Natural History Museum and author of "The Birds of San Diego County." "Many species which nest in San Diego County have declined greatly in abundance during this century."
In his book, the first review of county birds published in more than 25 years, Unitt divides county habitat into several types: desert, peninsular mountain, lowland and coastal. One of the outstanding features of North County geography is its coastal wetlands.
"Each of the North County lagoons varies appreciably from the others," Unitt says. "They differ in depth, amount of fresh water, type of vegetation and degree to which they have been silted."
Most North County lagoons combine fresh and salt water habitats, and Buena Vista, Batiquitos and San Elijo, as well as the mouth of the Santa Margarita River, boast the largest numbers of birds and some of the best spots for watching birds--including terns, pelicans, herons, egrets, cormorants, ducks, gulls and grebes.
These wetlands provide important nesting areas for some species, but also essential stopping and refueling places for migratory birds.
Bird counts, separate from the Christmas counts, are held regularly at several North County lagoons. Terri Stewart, wildlife biologist for the California Department of Fish and Game, and Herbert Williams, president of the Buena Vista Audubon Society, meet for the monthly bird count at Batiquitos Lagoon.
As a science, ornithology, or the study of birds, is unique, because professionals welcome the help of amateurs. In fact, many topics would never be studied at all were it not for the interest of non-professionals like Williams, a retired college professor.
On this Friday, Williams and Stewart and a handful of amateur birders fanned out and conducted the census of observed species around Batiquitos.
With the aid of binoculars and telescope, they count mallard and pintail ducks, black-necked stilts and avocets. They even spot a lone sora rail out in the open, a rare occurrence. At one point, a red-tailed hawk played tag with another bird of prey, an American kestrel.
Counting birds may seem an easy project to the uninitiated, but the best birders have years of experience not only in making visual identifications, but also knowing the habits, preferred habitats and calls of specific species.
As biologist Stewart explains, many of the endangered species in the county, like the Bell's vireo and the clapper rail, can usually only be identified by sound.
To make matters just a little more confounding, males of a particular species often look different than females, and fledglings look different than adults. Members within a family may have subtle variations in appearance, and feathering during breeding season may change.