About the Maps

This map presents an easy-to-navigate interface to 584 million avian observation records at over 15,000 locations in the state of California.

At present, the data is pulled from a variety of sources in the Bird Monitoring Data Exchange format (BMDE).

PRBO Pointcount data collection is ongoing and additional data will be added as it becomes available. Point count surveys measure bird abundance and diversity and can be used to measure habitat sustainability, population trends, and habitat associations in bird populations. Aside from providing the bird species and numbers detected at each point count location, this dataset is also a record of the location of point count locations so that surveys can be repeated in subsequent years. For more information on point counts (eg, background information, methodologies, data forms, and field protocols) see http://www.prbo.org/cadc/songbird/pc.php. PRBO data on this map is limited to observations which project leaders are able to share with the general public, and excludes data collected on private land or otherwise restricted by external circumstances. PRBO Banding data is continually collected at our Palomarin Field Station, as well as at other songbird monitoring sites. The PRBO At-Sea locations represent a fraction of the data collected by PRBO's Marine Ecology Division. In addition, PRBO hosts data for institutions such as the Ventana Wildlife Society and Klamath Bird Monitoring Network.

The Breeding Bird Survey results for 1997-2005, within the state of California, are also available. The North American Breeding Bird Survey (BBS), which is coordinated by the Biological Resources Division and Canadian Wildlife Service, is a primary source of population trend and distribution information for most species of North American birds. The BBS was initiated during 1966 by Chan Robbins and his associates at the Patuxent Wildlife Research Center to monitor the populations of all breeding bird species across the continental U.S., Canada, and Alaska. Approximately 2200 skilled observers participate in the survey each year. The BBS has accumulated 30 years of data on the abundance, distribution, and trends for more than 400 species of birds. These data are widely used by researchers, various federal and state agencies, non-governmental organizations, and the general public. Analyses of BBS data by PWRC statisticians have been instrumental in the development of innovative approaches for analyzing trends of wildlife populations.

Finally, eBird is a citizen science project. Our eBird data is refreshed nightly by an automated process and will generally offer the most recent observational data available. Developed by the Cornell Lab of Ornithology and the National Audubon Society, eBird provides a simple way for birders to keep track of the birds they see anywhere in North America. You can retrieve information on your bird observations, from your backyard to your neighborhood to your favorite bird-watching locations, at any time for your personal use. You can also access the entire historical database to find out what other eBirders are reporting from across North America. In addition, the cumulative eBird database is used by birdwatchers, scientists, and conservationists who want to know more about the distributions and movement patterns of birds across the continent. The location of Ebird markers may vary from the location where birds were actually observed by several hundred meters or more.

About the counts
Numbers indicate a rough measure of detection and do not account for effort, survey methodology or multiple sightings of the same individuals. These are not reliable measurements of abundance and may not include all the data for the species. For more appropriate estimates, use the CADC Analyst tool.

About abundance and richness estimates
Results are presented as general indicators of the quality of a location. Estimates do not account for ecological factors and do not include all the data for a particular site. For more appropriate estimates, use the CADC Analyst tool.

For Point Count and Area Search data, only observations within 50m of the observer are included in the calculation of the estimates. For banding data, only records with net-hour values are included. Estimates of abundance are obtained by averaging counts across all visits to each Point Count point, Area Search plot or banding station in a year. Transect estimates for Point Count data are obtained by averaging the point estimates, thus producing a poin-level estimate of abundance for each transect. Richness estimates are obtained similarly, using the count of species in each visit as the measurement parameter instead of count of individuals. In all abundance and richness graphs, the error bars mean +/- 1 standard error. Linear trends are estimated via a simple linear regression; if all records have non-zero variance, the records are weighed by the inverse of their variances. Full description of the methods for estimating abundance and richness can also be found in the Analyst tool.

Number of observations tracked on this map: 583,977,015

The most recent observation is dated: 2019-04-24

Related Links:
Avian Knowlege Network
The Institute for Bird Populations
Klamath Bird Observatory
Redwood Sciences Lab
Ventana Wildlife Society