Revision of Breeding Bird Survey of North America from Mon, 2015-04-13 04:45

The North American Breeding Bird Survey (1966-present) consists of data on the diversity and abundance of summer bird assemblages at approximately 5000 sites across the continental U.S. and Canada. Sampling began in 1966 and many sites have time-series that are at least 20 years long.

About BBS

The North American Breeding Bird Survey (BBS) was formally launched in 1966 when approximately 600 surveys were conducted in the U.S. and Canada east of the Mississippi River. Today there are approximately 3700 active BBS routes across the continental U.S. and Canada, of which nearly 2900 are surveyed annually. Breeding Bird Surveys are conducted during the peak of the nesting season, primarily in June, although surveys in desert regions and some southern states, (where the breeding season begins earlier), are conducted in May. Each route is 24.5 miles long, with a total of fifty stops located at 0.5 mile intervals along the route. A three-minute point count is conducted at each stop, during which the observer records all birds heard or seen within 0.25 mile of the stop.

Official BBS Website

Acquiring BBS

BBS Raw Data

FTP site

Supplemental resources 

BBS Survey Routes map layer available at: http://sagemap.wr.usgs.gov/FTP/unitedstates/NATLAS/birdm.htm

GPS coordinates for individual point count stops exist for some BBS routes, but at present (April 2014) are no longer hosted on the BBS website. They used to be found by clicking the 'Raw Data' link, then 'Enter Retrieval System', then 'Retrieve Raw Data', then 'Stop Location Data'.

GPS coordinates for some Canadian BBS routes (~70% as of 22 May 2014) are available from the National BBS Coordinator for Canada (BBS@ec.gc.ca). A full metadata file is in the works, but for now Marie-Anne Hudson of Environment Canada writes:

"The file contains the route file (ROUTES) as well as a STOPS file and the START and END point file (same as locations for stops 1 and 50 in the STOPS files). Please note that the data presented here are to be used at your discretion. Though many have been vetted by BBS observers, many have not. It is not presented as fine-scale data (e.g., <100 m resolution). Its usefulness will depend on the scale being examined (e.g., it is likely fine at the route scale or 10-stop scale, but perhaps inaccurate at the stop scale).

Active (route is Active Yes = 1, No = 0). There are routes with several pieces sometimes; these represent historically run sections of the route. A 3 indicates a skipped section in the route (usually for safety reasons).

Any use of Canadian BBS data should acknowledge the hundreds of skilled volunteers in Canada who have participated in the BBS over the years and those who have served as provincial or territorial coordinators for the BBS. In addition, anyone working with BBS GIS data should also acknowledge the hard-working folks with the Boreal Avian Modelling Project (BAM; www.borealbirds.ca), without whom this information would not be available."

Using BBS

Best practices

• For community analyses it is generally best to exclude nocturnal, crepuscular, and aquatic species as they are not well sampled.
• Surveys where RunType in the Weather table is 0 should be excluded as this indicates a survey that does not pass quality standards.
• Only use the Run Protocol IDs (counts.RPID) that are appropriate for your study. If you just want standard BBS surveys, use RPID = 101.
• StopTotal is a measure of incidence (presence/absence), SpeciesTotal is a measure of abundance.

Additional considerations

Be aware of taxonomic changes, and check to make sure that subspecies are not being treated as separate species or that separate species are not being treated as a single species in your analysis.  This is especially relevant if you are interested in making comparisions over a long time period.  Sampling effort is not equal across North America, which is also a factor to take into consideration.