|Status survey and conservation planning for Black Crowned Cranes
In 2000, ICF and Wetlands International launched a comprehensive program to assess the status of Black Crowned Cranes in Africa and develop concrete plans for the conservation of the species across its range. Emmanuel Williams from Sierra Leone served as project coordinator during the first phase of this program from 2000-2001, based at the Wetlands International office in Dakar, Senegal. Recently, Cheikh Diagana from Mauritania took over guiding the program through the second phase. Tim Dodman of Wetlands International and Richard Beilfuss of ICF are project supervisors.
During 2000-2001, we conducted the first-ever, range-wide surveys of the species covering fifteen West African nations and five East African nations. We used a combination of ground surveys, aerial surveys, questionnaires, interviews, and reliable past records and reports to assess the population size, distribution, and habitats of the species, and the threats to its survival. Survey participants included members of the African Waterbird Census (AfWC) network of Wetlands International, the ICF crane working group network in Africa, the Foundation Working Group International Waterbird and Wetland Research (WIWO), the National Hunting and Wildlife Office of France (ONCFS), and many other organisations and individuals. A total of 226 sites were targeted for surveys. These included all sites known to currently or recently harbor Black Crowned Cranes, as well as sites where cranes were thought to have historically occurred and sites never previously surveyed that would likely support cranes. Survey sites were identified from the AfWC database, previous reports and publications, and personal communication with survey participants.
During the first year, a total of 125 of the 226 targeted sites were covered by field surveys or questionnaires. In 2002, gap-filling surveys targeted many sites not covered in 2001, especially the Casamance River, parts of southwestern Mali, and southern Sudan. The surveys were supplemented by interviews with village leaders in key habitat areas to assess local attitudes about Black Crowned Cranes and generate ideas for meaningful conservation projects in those communities where cranes are most threatened.
Sub-populations of Black Crowned Cranes were assessed in terms of specified ecological units (e.g., deltas, river basins, catchments, or other wetland complexes), referred to as Crane Areas, that were determined during the survey. The thirty-eight Crane Areas enable a closer examination of changes in the status and distribution of Black Crowned Cranes and the location-specific threats to their survival, and provide a focal point for future conservation measures. Because the Crane Areas are based on ecological rather than political units, many extend beyond national boundaries and highlight the need for international cooperation in monitoring and conservation. For example, the Lower Senegal River Basin Crane Area covers northern Senegal and southwestern Mauritania and the Lake Chad Basin Crane Area covers parts of Niger, Nigeria, Cameroon, and Chad. The survey suggests that Black Crowned Cranes can be considered year-round residents in most of the Crane Areas, although local seasonal migration occurs between a few of the Crane Areas.
Our surveys confirm that the West Africa Crowned Crane subspecies is rapidly vanishing across much of its range, but still persists in good numbers in Chad and Cameroon (See Map). We estimate a population of about 15,000 West Africa Crowned Cranes–earlier population estimates from various portions of the range suggest much higher numbers prior to the 1970s. Sudan remains the global stronghold for the species, but further surveys are needed; (we estimate somewhere between 25,000-55,000 Sudan Crowned Cranes, depending on how the numbers are extrapolated).
After completing the surveys, we drafted a Black Crowned Crane Action Plan. This plan was reviewed by key survey participants from 16 African nations at a roundtable discussion, convened at the 10th Pan-African Ornithological Congress in Uganda. Roundtable participants also recommended two case study projects to investigate key threats in the Inner Niger Delta and the Senegal River Valley. The Action Plan provides details of the survey methods and analysis, and describes population status, distribution and seasonal movements, breeding ecology, feeding ecology, protection status, threats to cranes, and local attitudes about cranes. Recommended conservation actions are provided on a range-wide and sub-species basis.