Most people know the Philadelphia suburbs for cheesesteaks and unruly sports fans. But it’s no wonder that John James Audubon started his lifelong affair with birds just 25 miles northwest of Center City, and a 20-minute drive from my natal stomping grounds. The dense, rolling woodlands of Pennsylvania’s Montgomery County where I grew up offered prime habitat for cardinals, chickadees, blue jays, wrens, and countless other species my mom loved to point out to us kids. I didn’t realize it at the time, but my mom’s avian affinities taught me not just to pay attention to the biology in my backyard but, ultimately, to consider which species lived there and why.
This weekend, novice Bay Area wildlife watchers get the chance to play field biologist in their own backyards and join forces with expert birders and scientists to gather data on the incidence, abundance, and distribution of birds. Between February 17 and 20, the 15th annual Great Backyard Bird Count invites people of all ages and experience to spend as little as 15 minutes (or as long as you like) counting birds wherever you are.
“The Great Backyard Bird Count is an excellent introductory citizen science project for any level of birder,” says Brian Sullivan, an expert on North American birds and project leader of Cornell’s online resource for birders around the world, eBird.
“You can just count the birds you see in your backyard or go to your local park and count what you see there. The idea is to get a weekend snapshot of late-winter bird distribution across the United States and to make things really simple so just about anyone can participate.”
Sullivan, who has 1,669 species on his life list, says lucky birders could see “mega-rarities” like an Iceland gull, “a very rare bird in California” spotted near Sausalito in early February, or maybe the dusky-capped flycatcher that's been living in Golden Gate Park all winter.
The largest estuary on the West Coast, the San Francisco Bay Delta provides habitat and refuge to more than 250 species of waterbirds, some (including pelicans, loons, herons, and egrets) year-round residents, others, like the Wilson’s phalarope and Sabine’s gull, on stopovers to feed and rest before resuming their long-distance migrations. As many as 800,000 birds inhabit Bay Area waterways at any given time.
To find out which birds you’re likely to see in your area, go to Cornell’s eBird, click on “View and Explore Data,” then click on “Bar Charts,” select “United States,” “California,” and then “Counties in California.” Choose your county, click “continue,” and you’ll see the occurrence of birds throughout the year.
Last year, participants entered more than 92,000 checklists with 1.4 million birds from 596 species. Their data helped researchers identify changes in abundance (including an increase in evening grosbeaks, which declined 50% between 1988 and 2006) and distribution (winter finches moving south), and spot anomalies (an Asian brown shrike in McKinley, California).
The bird counts give weekend nature lovers an easy way to help scientists gather data on a widely distributed group of animals that serve as valuable indicators of biodiversity. Because birds occupy many different “trophic” levels in food webs, eating everything from insects to fish to mammals (and, for top predators like owls, hawks, and eagles, other birds), they play critical roles in maintaining healthy ecosystems. Among their many “ecosystem services,” all of which benefit humans, birds help regulate prey populations, facilitate plant reproduction through pollination and seed dispersal, and recycle nutrients by scavenging carcasses.
This widespread influence on their environment also makes them extremely sensitive to ecosystem disruptions, including habitat destruction and climate change. An alarming 13% of the world’s birds, 1,253 species, face extinction, according to the 2011 IUCN Red List. The Great Indian bustard, a native of India and Pakistan that barks when alarmed, has been reclassified as critically endangered, a victim of hunting and widespread habitat destruction. Scientists think fewer than 250 mature birds remain.
Closer to home, black-crowned night herons and snowy egrets have been on a downward slide since 2005. And the endangered California clapper rail, once abundant in the tidal marshes of San Francisco Bay, offers a case study in the unintended consequences of development. Extensive filling and diking of the bay has destroyed some 85% of the clapper rail’s salt marsh habitat, making a shy species that seems to prefer scampering over swimming and flying easy pickings for feral cats and invasive red foxes, which now have unfettered access to adults and their ground-nesting offspring.
Roughly 60% of the critically endangered clapper rail population, estimated at between 1,000 and 1,500, lives in San Francisco Bay’s Don Edwards National Wildlife Refuge, in Fremont.
Researchers will use the information collected from the bird count to learn how birds like the clapper rail are coping with these new predation pressures, as well as other stresses from ongoing urbanization, global climate change, and disease.
The decline of suitable habitat for these species affects us as well. Tidal marshes filter contaminants to enhance water quality and serve as natural flood barriers. If the marshes can no longer support species like the clapper rail, chances are they can’t provide these ecosystem services for us either.
Birds are among the most diverse and ubiquitous vertebrates on the planet and often offer humans a first brush with wildlife.
As a little girl, I marveled that my mom always knew when Jenny Wren and her husband, Joe (as she liked to call the resident house wrens), would appear in our backyard, build their nest, and settle into the business of raising, feeding, and protecting their broods.
She couldn’t have known that scientists would one day blame the precipitous declines in Bewick’s wrens in the eastern United States on the expansion of her beloved house wrens, known for ejecting eggs, and even young, from coveted nest sites.
As I listened to Mom’s fanciful tales of avian domestic dramas, my young imagination conjured all manner of worrisome scenarios. Would Joe find enough food for the babies? Could Jenny protect them from a torrential summer downpour? How would either of them cope with a curious cat? Some may shudder at such anthropomorphizing, but I wonder: If more people viewed birds the way my mom did, struggling to survive like the rest of us, would they worry about their welfare, too?
Henry David Thoreau first said “In wildness is the preservation of the world” in a lecture some months after Audubon’s death. I like to think, had they discussed the question, Audubon would have objected: “My dear sir, I believe you meant to say, ‘In birds is the preservation of the world.’ ”