The application of Criterion 6 for the designation of Ramsar sites


The application of Ramsar Criterion 6 for the designation of Wetlands of International Importance:

Waterbird Population Estimates 2nd edition now available on the Web

Wetlands International, as a part of its key role as an International Organisation Partner (IOP) in providing scientific and technical support to the Ramsar Convention, periodically prepares a global summary of best available information of the status and trends of waterbird biogeographic populations, drawing on the data compiled through their International Waterbird Census and the expertise of their extensive waterbird Specialist Groups network. The most recent publication is Waterfowl Population Estimates 2nd edition, published by Wetlands International in 1997.

Waterfowl Population Estimates 2nd edition has, however, been out of print for some time, and Wetlands International have now made the volume available for downloading, in PDF format, from their Web site at

For all populations for which there is adequate information on the total size of the population, Waterfowl Population Estimates 2nd edition provides recommended 1% population thresholds for the application of Ramsar Criterion 6 for the identification and designation of Wetlands of International Importance. Criterion 6 says that "A wetland should be considered internationally important if it regularly supports 1% of the individuals in a population of one species or subspecies of waterbird."

Ramsar's COP6 (Brisbane, 1996) Resolution VI.4 calls on Contracting Parties to use these estimates and thresholds in Waterfowl Population Estimates 2nd edition as a basis for designating Ramsar sites under Criterion 6. The Convention's Strategic Framework and guidelines for the future development of the List of Wetlands of International Importance (Resolution VII.11) provides guidance to Contracting Parties on the application of this Criterion.

Wetlands International is currently preparing a 3rd edition of Waterbird Population Estimates, which is planned to be available by Ramsar COP8 in November 2002, and which will include substantial review and updating of population estimates, 1% thresholds for a number of populations for which there was no previous information, and a number of new features designed to improve its ease of use in applying Criterion 6 by those responsible for the preparation of Ramsar Information Sheets for Ramsar site designation.

As well as providing a key source of information for the identification and designation of Ramsar sites for waterbirds, Waterbird Population Estimates also presents information for implementation of the African-Eurasian Waterbird Agreement (AEWA), an Agreement under the Convention on Migratory Species (CMS). The AEWA Action Plan and Report on the Conservation Status of Migratory Waterbirds in the Agreement Area has used Waterbird Population Estimates as its primary source for most population estimates and trends. Development of flyway site networks for migratory waterbirds, through the use of population estimates to identify key sites, is a focal topic of joint activity in the Ramsar-CMS/AEWA Joint Work Plan that is being finalised in early 2002.

Nick Davidson
Deputy Secretary General

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Number of » Contracting Parties: 168 Sites designated for the
» List of Wetlands of
International Importance
2,186 Total surface area of designated sites (hectares): 208,674,247

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