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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