International Shorebird Surveys

Volunteers For Informed Conservation Programs

In 1974 the Manomet Center for Conservation Sciences organized the International Shorebird Surveys (ISS) to gather information on shorebirds and the wetlands they use. One motive was to learn how various species depend on particular wetlands and migration corridors. Having fostered some 80,000 census counts from more than 1200 locations, the take-home message now is clear; many species of shorebirds depend on strategic migration staging sites.

Information gathered by ISS cooperators over the last 30 years show some disturbing trends. The data have long suggested that several shorebird species were declining rapidly, but until recently the design of the ISS did not allow for a sensitive statistical analysis. A new initiative called the Program for Regional and International Shorebird Monitoring (PRISM) is underway to coordinate and expand on existing shorebird survey efforts, including the ISS, the Western Shorebird Survey and the Canadian Maritimes Shorebird Survey. The closer coordination and expanded survey effort will increase the power of statistical analyses and more clearly define shorebird conservation issues on a continental scale. These new sites are considered "ISS/PRISM focal sites" or "focal sites" for ease of communication.

ISS/PRISM Guidelines and Information

Background:
Shorebirds are hemispheric globetrotters whose migrations include long-distance, nonstop flights often exceeding a thousand miles. To complete these extraordinary flights shorebirds must lay on large fuel reserves. In many of the 40 common North American species fat is accumulated at food-rich staging areas. There apparently are few places having the right combination of resources, for in some cases between 50 and 80% of the entire population of a species may visit a single site. It therefore appears that loss of critical staging areas could devastate hemispheric populations.

Most shorebird staging sites are marine or nonmarine wetlands. According to governmental studies, there are roughly 90 million acres of wetlands in the lower 48 states, 95% of which are nonmarine and located inland; the balance are marine or estuarine. More than half of the US wetlands have been destroyed since European settlement, including more than 90% in some key states like California and Iowa. In spite of regulations, wetland conversion and destruction is proceeding; mitigation attempts evidently are not successfully replacing the critical wildlife resources that are lost. Today most wetland wildlife species are in population decline; according to a 1995 study, at least 16 of 26 shorebird species examined were threatened or in serious population decline -- 1 was increasing.

These reports and the ISS data confirmed the need for forming the Western Hemisphere Shorebird Reserve Network (WHSRN), a program that works to build protection for strategic migration sites. ISS data also have been used in identifying sites in North and South America that qualify for inclusion in WHSRN, for charting migration timing at key sites, and for developing an atlas to provide conservation and wildlife professionals basic information needed for making effective decisions.

Because shorebirds are hemispheric globetrotters, documenting their migrations requires a large information-gathering network that spans all of the Americas. Costs of paying for this work would be prohibitive, so the ISS is developed around a volunteer base to gather needed information. To date more than 900 people have contributed information; the project is ongoing and continues to need additional volunteer help.

ISS data are used principally for conservation and management initiatives. During the last 5 years ISS evaluations have helped formulate practices in federal agencies as varied as the U.S. Forest Service, the Department of Defense, and the U.S. Fish and Wildlife Service, as well as dozens of state agencies. ISS data have provided pivotal information used in federal and state management training programs. Data also are provided to researchers who meet program conditions.

The ISS data files now include almost 80,000 censuses, with about 1300 added each year by 50-100 cooperators. Cooperators are asked to census a location selected by the cooperator three times monthly during key migration periods. Less frequently collected counts also are welcome, especially from regions where information is sparse. Researchers planning other uses for their data may contribute with restrictions on how their data may be used, or they may archive appropriate data with the ISS on completion of projects.

For additional information, please download our 2009 newsletter or contact:

The International Shorebird Surveys
Manomet Center for Conservation Sciences
PO Box 1770
Manomet, MA USA 02345
bharrington@manomet.org
Voice: 508-224-6521
Fax: 508-224-9220