Wednesday, January 29, 2014

Citizen Science, come rain, wind or shine: Christmas Bird Counts


Written January 22, 2014, published in late January 2014

In mid December, I took part in two bird counts on the South Coast of Washington. The Christmas Bird Count organizes thousands of people in the Americas to count birds in well-defined geographic areas, called 'count crcles'. These circles are fifteen miles across. Our local circles are centered, respectively, near the Columbia River and Willapa Bay entrances. There are thousands of count circles in North America, from above the Arctic Circle into Mexico, and in the past couple of decades, new ones have been defined in Central and South America, as well as just upriver in Skamokawa.

Robert Zimmerman, Mike Patterson and Kathleen Sayce look for birds on Willapa Bay at the Port of Peninsula, photo by Jackie Ferrier

Christmas Bird Counts began 114 years ago in New York City, as an alternative activity to the tradition of the day, which was to shoot as many birds as possible on one day. Not kidding. A local group decided to visit Central Park and see how many bird species they could see, rather than shoot, after Christmas 1899. It has metamorphosed into two continents-wide tracking of bird populations, and is now the longest running citizen science project on Earth. Sponsored by the National Audubon Society, you can read more about the history of Christmas Bird Counts at http://birds.audubon.org/christmas-bird-count . Recent reports on counts are also posted on this site.

Mike Patterson at dawn with spotting scope, Nahcotta, Willapa Bay, photo by Kathleen Sayce 


As with plants and other biotic groups, bird species diversity (the number of species found in an area) is higher closer to the Equator and lower towards the poles. We are lucky here to see one hundred twenty species in each count circle, and have not quite reached one hundred fifty species in especially salubrious years. In subtropical south Texas, a typical count includes more than two hundred species, and there are circles in South America that average more than four hundred. Above the Arctic Circle, one count circle celebrated when they finally saw one bird, a raven, after years of watching and seeing no birds at all.

Black Turnstone on shell pile, Port of Peninsula on Willapa Bay, photo by Mike Patterson


Looking for birds is chancy in late fall and early winter in this area. Days are short, with fewer than eight hours of daylight, and air temperatures are rarely above 50 F. Usually it rains, often it also blows. Some years, it snows. In storms and strong winds, birds hide, and we are lucky to get forty species and two hundred birds in one section. As the pressure drops ahead of a storm, birds seek shelter, so even in fairly nice weather if the barometer is falling, the birds hide. About one year in ten the weather is dry and more or less sunny, though some sunny count days can be very windy. Birders layer up in warm clothing, wear rain gear, waterproof boots, warm hats, and often snack all day long. They carry binoculars, cameras, cell phones, and spotting scopes, with field guides and notes about where to see certain rare species.

And then the fun begins: Each circle is divided into several sections, because no one can traverse the area of a circle fifteen miles wide and see all the birds, even on flat land with roads everywhere. Eight to ten sections per circle are typical, each one covering several square miles. In more densely populated circles, sections may be as small as a few blocks. In the local circles, much of the area is over water, which must be surveyed by boat.

Mike Patterson and Kathleen Sayce birding with spotting scopes south of Oysterville on Willapa Bay,  near noon during the count day, photo by Jackie Ferrier


This year I worked the Chinook section of the Astoria Circle, which starts at the bottom of the north side slope over the shipping channel on the Astoria-Megler Bridge with two other people. Starting just after daylight, our task was to count as many individual birds as we could, and sort all of them into species. We can't stop on the bridge to do this, so we had a designated driver and a note taker, and everyone focused on how many birds of which species were seen on each side of the car crossing the bridge. Some years it's less than twenty gulls; some years it's more than five hundred, along with cormorants, eagles and ducks. And that's the first five minutes, just after sunrise. It can be quite a rush to bird this intensely all day.

The highest numbers of birds and species for any area are always seen in sunny calm weather. It helps to have local bird feeders to visit during the day. Even a few days of putting out bird seed will draw in birds in winter. Walking or bicycling rather than driving helps, though hybrid cars are so quiet when running on batteries with all the windows down that we can hear birds almost as well as when walking. Both local circles include a lot of open water, so in calm weather some birders go out in boats to count on the water. Owls are active before dawn, so a birder skilled in birding by ear often starts around four or five a.m., hunting for owls late at night. Having more birders looking helps too; the more eyes looking means more birds are seen.

Routines have changed over the years. In past decades, sketches and field notes on rare birds were submitted by mail, and then argued over weeks later. With cell phones, uncertain bird identifications can be discussed quickly, and spectacular sightings of rare birds or unusually high numbers of common birds are shared during the day. Digital photos help too; photos sent around during the count day can usually resolve identification problems quickly.

From year to year, the species with the highest number of individuals changes for each circle and each section. One year, there were more than fifteen thousand birds in Bakers Bay––gulls, ducks, cormorants, including seventeen Bald Eagles––all eating fish after an unusual fish kill occurred. Another year, all the loons and grebes were upriver of the Astoria-Megler Bridge instead of spread throughout the count circle. This year, in five miles along Willapa Bay, there were more than nine thousand Northern Pintail ducks. Some years Black Brant have not arrived on Willapa Bay by the day of the count, but there were several thousand brant on the bay this year, arriving just a few days earlier.

In the past decade, the Eurasian Collared Dove arrived in eastern North America, and a few years ago, made it to the West Coast. It crowded out Rock Dove populations everywhere, which was until then an ubiquitous urban bird. In urban areas, several species of parrots have escaped and established viable populations. An occasional winter visitor a decade ago, Anna's Hummingbird is now a common year round resident. Likewise, Western Scrub Jays have gone from occasional visitors, driven down out of the mountains in bad winters, to common at sea level. We saw all these species in both count circles this year. No parrots, however.

There are other Citizen Science projects to participate in: Around the 4th of July is an annual butterfly count (http://www.naba.org/butter_counts.html ); backyard bumblebee tracking goes on spring through early fall (http://www.bumblebeewatch.org ) ; bud break of common yard plants each spring goes on across North America (http://budbreak.org ). I've participated in butterfly counts, and plan to track bumblebees in my yard during the next growing season.

The winter bird count is special, however, because weather is such a strong determiner of what it will be possible to see. If we are lucky, it's a quiet day of great natural beauty with active birds to see all day long. This year, the weather was mild on both days and no one got hypothermia. Next winter, when you see a slow moving car or group walking down the road around Christmas, bristling with binoculars and spotting scopes, wave and know the CBC is underway for its 115th year.





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