SAN FRANCISCO (CBS SF) — More than 550 bird watchers will scour parks, shorelines and their own backyards in Oakland, Richmond and San Francisco over the next two weeks for the Golden Gate Audubon Society’s annual Christmas Bird Count.

The count, on hiatus last year due to the pandemic, tallies as many birds as possible in a single day in the three cities, starting with Oakland on Sunday. The birders will focus on San Francisco on Dec. 28 and then Richmond on Jan. 2.

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“A lot of people got into birds during COVID, now some of them are coming to join the count,” said Siobhan Ruck, co-organizer of the San Francisco count. “We actually have quite a few more beginners on the list this year, some of whom just started birding a year ago.”

The Audubon Society’s 122-year-old bird count is a citizen science project that provides insight into the health of bird populations, along with the general health of the environment, organizers said.

This year, Richmond was added to the Golden Gate Audubon Society’s count, which has historically focused solely on Oakland and San Francisco.

Each count aims to identify and record every individual bird encountered within a defined 15-mile-diameter circle — about 177 square miles — during one calendar day.

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In recent years, the Oakland count has had more participants than any other such event in the world, only to be outdone in 2019 by Victoria, British Columbia, according to organizers.

The last Oakland count recorded more than 186 bird species in 2019; the San Francisco count generally averages 175 species.

Tallies from the local counts will contribute to the National Audubon database, which tracks the health of local and nationwide bird populations.

In 2019, the Audubon’ annual count mobilized over 81,000 volunteer bird counters in more than 2,600 locations across the Western Hemisphere.

More information on the Oakland, Richmond and SF counts is available at https://goldengateaudubon.org/birding-resources/christmas-bird-counts/.

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