Program for Regional and International Shorebird Monitoring (PRISM)


PRISM is a complementary monitoring effort to the International Shorebird Survey (ISS) coordinated by the Manomet Center for Conservation Sciences. ISS originated in 1974 to gather data on shorebirds and wetland use. Since then it has grown such that in 2009 almost 80,000 census counts were completed at 1200 locations in 47 states of the U.S., with additional counts from Central and South America. PRISM was later developed as a complementary project aimed at better tracking population change in shorebirds and at better informing the U.S. Shorebird Conservation Plan. It expanded the ISS survey effort to increase the power of statistical analyses and more clearly define shorebird conservation issues on a continental scale. PRISM goals were most recently revised in 2007 to include the following: 1) identify species at risk, 2) contribute to the identification of causes of declines or other disturbing trends, 3) help develop, evaluate, and refine management/conservation programs, 4) document progress towards, or away from, management/conservation objectives, and 5) assist managers and policy-makers in meeting their shorebird conservation goals. Data are collected primarily from ISS/PRISM focal sites but surveyors can select their own sites using data entered by the volunteer into the ISS eBIRD portal. Volunteers are asked to count all birds they see to the species level. If the tally is a count, volunteers are asked to submit an estimate or a guess of the total number. Birds are recorded as “identified” if observers can identify to species level; otherwise they are simply quantified to a group (e.g., peeps). Guidelines are available online and provide dates for fall and spring migration survey periods, time of day and location, and includes pointers to improve count accuracy.


PRISM demonstrates peer-reviewed methods, scientifically sound data collection, and a collaborative approach with multi-partner support.  Among the benefits of PRISM surveys is long term trend data and the establishment of annual peak migration periods by species. In areas where human disturbance is a factor, these surveys may offer some insight on shorebird impacts resulting from habitat perturbations. Volunteers collect data based on a clearly defined protocol (specific survey periods, time of day, locations) with explanations for count accuracy and species identification. Data entry is online through the ISS eBird website.  


Data is primarily collected by volunteers interested in contributing to the database. Like all volunteer populated databases effort can vary within and across sampling periods and years but without volunteers this type of monitoring effort would be cost prohibitive. The protocol may be less effective in geographic areas where configuration and uneven topography of the habitat interferes with detectability of target species. For instance, salt marshes are often interspersed with mudflats surrounded by vegetation that make it virtually impossible to locate foraging shorebirds, which can lead to substantial underestimates of birds in a given system. There is a potential of double counting when conducting migratory bird surveys over large areas which may take several days to complete.

Examples of use

PRISM is being implemented by a Canada-U.S. Shorebird Monitoring and Assessment Committee formed by the Canadian Shorebird Working Group and the U.S. Shorebird Council. 

For more information (protocol and data entry) - General info on PRISM - Peer review of PRISM methods