Community Science

Scientists use information from these community science projects to get the “big picture” about what is happening to bird populations. The longer and more broadly these data are collected, the more meaningful they become in helping scientists investigate far-reaching questions.

Christmas Bird Counts

Every year MDAS participates in the National Audubon Christmas Bird Count (CBC).  Ocurring annually since 1900, the CBC is the longest running community science project in the world.  Participating in this this popular community science project is one of our Chapter’s most significant efforts to promote conservation and fellowship among our birding community.   MDAS sponsors two counts, one in central Contra Costa County (since 1955) and one in East County (since 2000).  A count must occur between December 14th and January 5th.  We have the good fortune of being able to access some private, privately-managed, and off-limits public lands for both of our counts. Such access is due to the goodwill that our chapter leaders have established over the years. We can be proud of that!

If you live within our count circles, you may choose to watch your own yard on count day and submit the data. Use the circle links below and zoom in to view our Circles: Central County – East County – Both circles on one map

Since 2019, we have been using eBird to compile CBC data. To see CBC results from prior years since the advent of eBird compiling, click the links below. These Field Reports show what, how many, and where birds were seen (Note: sensitive species are not shown).

2021 Central County East County
2020 Central County East County
2019 Central County East County


FeederWatch (November – April)

Visit: Project FeederWatch – Sign up anytime!

FeederWatch, a Cornell University project, records the movement of migratory birds across the continent and runs seasonally from November to April. Following a specific protocol, participants record what birds are seen at the feeder during a set period of time on a weekly basis. Effort and weather conditions are reported as well as species and numbers. You’ll improve your observation skills and holistic understanding of species by spending concentrated time with your backyard birds. In addition you may become involved with a larger community of birders nationwide who provide photos and comments about their experience. You may begin participating at any time during the annual project.

Great Backyard Bird Count (February)

Mark your calendars: February 12-15, 2021

The Great Backyard Bird Count has been held every February since 1998. A joint project of Cornell Lab of Ornithology and National Audubon Society, it provides a snapshot of what birds are where just before the beginning of Spring migration on our continent. Participants report online what species and how many individuals they see on any of the four days during the event in a time frame and location of their own choice. If you are a regular eBird reporter, simply report as usual during the four days and your data will be included since eBird and the GBBC are completely integrated. The Count went global in 2013 and now has numerous checklists from more than 130 countries. The GBBC was the first online citizen science project to collect data on wild birds and to display the results in real time. It is an event that lends itself well to group outings. Only one participant needs to report the results. MDAS encourages its members to participate in this project because of its contribution to an important ornithological data base.

The 2022 East Contra Costa County Count, within this count circle, is tentatively scheduled for Wednesday December 14.  Stay tuned for more information!
The 2022 Central Contra Costa County Count, within this count circle, is tentatively scheduled for Saturday December 17.  Stay tuned for more information!