Northern Prairie Wildlife Research Center
Subjects:
Summary
Subspecies/populations
Population Numbers and Trends
Conservation Status
Historic and Present Distribution
Distribution by Country
Habitat and Ecology
Principal Threats
Current Conservation Measures
Priority Conservation Measures
Summary
The Black-Crowned Crane is found in the Sahel and Sudan Savanna region of
Africa from the Atlantic coast to the upper Nile River basin. Two subspecies are
recognized. B. p. pavonina (the West African Crowned Crane), with an estimated
population of 11,500-17,500, occupies the western part of this range and is divided
into eight or more disjunct populations B. p. ceciliae (the Sudan Crowned
Crane), with an estimated population of 55,000-60,000, occurs in eastern Africa,
with the largest concentrations in southern Sudan. Historically, the species was
more numerous and more evenly distributed than at present. In the eastern part
of its range, its population is stable and relatively abundant. In the western
portions of the range, however, its numbers have declined and its range has been
reduced dramatically over the last two decades. The species is classified as Vulnerable
under the revised IUCN Red List Categories. B. p. pavonina is classified
Endangered, and B. p. ceciliae Vulnerable.
Black Crowned Cranes use both wet and dry open habitats, but prefer a mixture of shallow wetlands and grasslands (especially flooded lowlands in the sub-Sahelian savannahs). They can be considered both year-round residents and local migrants, flocking together during the dry (non-breeding) season and moving from large permanent wetlands to smaller temporary wetlands formed during the rainy season. Although they are non-migratory, daily and seasonal movements may in some areas range up to several dozen kilometers.
The principal threat facing the Black Crowned Crane is the loss, transformation, and degradation of its habitat. Behind this threat lies a combination of causal factors: extended drought in the Sahel and sub-Sahelian savannas, high human population pressures, intensive agricultural development and expansion, and extensive changes in hydrological systems as a result of dams, drainage, and irrigation projects. These factors are most pressing in West Africa, but also affect the species in the east. In some areas, these cranes are hunted for meat or captured and sold for trade. Ineffective enforcement of laws and the shortage of scientific research may also be considered long-term threats to the survival of the species.
The decline of the Black Crowned Crane in West Africa has begun to stimulate conservation efforts on behalf of the species. It is legally protected in most countries where it occurs, and many protected areas established in these countries harbor cranes. Several local surveys have recently been undertaken. In 1992, Nigeria hosted an International Conference on the Black Crowned Crane and Its Wetlands Habitat in West and Central Africa, and a Black Crowned Crane Coordinating Centre was established. No reintroduction program has been undertaken for the Black Crowned Crane, but the potential for reintroduction of the West African subspecies has been under discussion, and an experimental release has taken place in Nigeria.
Priority conservation needs for the species include: transfer of the species to CITES Appendix I; ratification of the Ramsar Convention by range countries and adoption of stronger national wetland protection policies and legislation; requirements for environmental impact assessments of large-scale development schemes affecting Black Crowned Crane habitat; increased support for existing protected areas and designation of new areas used by cranes; ecological research on wetlands and crane habitat requirements; a coordinated surveying and monitoring program for the species; collaborative projects involving local communities in the conservation and sustainable use of wetlands; establishment of a West African Crane Recovery Team; development of educational programs involving Black Crowned Cranes and wetlands; and expanded training opportunities for crane and wetland conservation specialists.
| West African Crowned Crane | B. p. pavonina |
| Sudan Crowned Crane | B. p. ceciliae |
The Grey and Black Crowned Cranes were combined within a single superspecies in the past, but are now considered separate species with two subspecies each. The subspecies of the Black Crowned Crane are most easily distinguished by differences in the coloration of their cheek patches. In B. p. pavonina, the lower half of the cheek patch is red; in B. p. ceciliae, the red extends into the upper half of the cheek patch (Johnsgard 1983, S. Haeffner pers. comm.).
| Subspecies | Number | Trend | Source |
| B. p. pavonina | 11,500-17,500 | Declining. Extirpated (or nearly extirpated) in some nations. |
Urban in press |
| B. p. ceciliae | 55,000-60,000 | Uncertain. Generally stable, but possibly declining locally. Still abundant, perhaps expanding in Sudan. |
Urban in press |
| Total | 66,500-77,500 | Declining | |
| Species | |
| IUCN Category | Vulnerable, under criteria A1c,d A2c,d |
| CITES | Appendix II |
| Subspecies | |
| West African (B. p. pavonina) | Endangered, under criteria A1c,d |
| Sudan (B. p. ceciliae) | Vulnerable, under criteria A1c,d A2c,d |
The Black-Crowned Crane is found in the Sahel and Sudan Savanna region of Africa from Senegal and Gambia on the Atlantic coast east to the upper Nile River basin in Sudan and Ethiopia (Walkinshaw 1964). Major wetlands—including the delta of the Senegal River, the inland delta of the Niger River in Mali, the delta of the Wazi River at Lake Chad in Camaroon, and the extensive Sudd wetlands in southern Sudan—are strongholds for the species (Eljack in press). B. p. pavonina occurs in the western part of this range, from Chad to Senegal, and is now thought to be divided into eight or more disjunct populations. B. p. ceciliae is found in eastern Africa, with the largest concentrations (an estimated 50,000 birds) in southern Sudan (Urban in press).
Historically, the Black Crowned Crane was more numerous than at present, and distributed more widely and evenly in the Sahel and sub-Sahelian savannas. The eastern portion of the population remains relatively abundant, although the population may be declining in eastern Sudan (Eljack in press). In western Africa, both the numbers and range of the Black Crowned Crane have declined dramatically since the onset of persistent drought in 1973 (Mustafa and Durbunde 1992). The drying up of wetlands, combined with increasing human population pressures, loss of habitat, and other threats, has fragmented the range of the subspecies and brought it to the verge of extinction in several countries. The population in Nigeria (where it was once abundant and is still the national bird) has been reduced to no more than 50-100 individuals (Urban in press, P. Hall pers. comm.).
| Country | Subspecies | Distribution Status |
| Benin | B. p. pavonina | r |
| Burkina Faso | B. p. pavonina | r |
| Cameroon | B. p. pavonina | R |
| Central African Republic | B. p. pavonina | r |
| Chad | B. p. pavonina | R |
| Congo | B. p. pavonina | U |
| Cote d'Ivoire | B. p. pavonina | r |
| Egypt | B. p. ceciliae | r |
| Equatorial Guinea | B. p. pavonina | U |
| Ethiopia | B. p. ceciliae | R |
| Eritrea | B. p. ceciliae | r |
| Gabon | B. p. pavonina | r |
| Gambia | B. p. pavonina | r |
| Ghana | B. p. pavonina | r |
| Guinea | B. p. pavonina | U |
| Guinea-Bisseau | B. p. pavonina | U |
| Kenya | B. p. ceciliae | r |
| Liberia | B. p. pavonina | U |
| Mali | B. p. pavonina | R |
| Mauritania | B. p. pavonina | r |
| Niger | B. p. pavonina | r |
| Nigeria | B. p. pavonina | r |
| Senegal | B. p. pavonina | R |
| Sierra Leone | B. p. pavonina | X |
| Sudan | B. p. ceciliae | R |
| Togo | B. p. pavonina | r |
| Uganda | B. p. ceciliae | r |
| R = Resident (population > 1000) | ||
| r = Resident (population < 1000) | ||
| U = Distribution Status unknown | ||
| X = Extirpated | ||
Black Crowned Cranes use both wet and dry open habitats, but prefer freshwater marshes, wetter grasslands, and the edges of water bodies. The West African subspecies prefers a mixture of shallow wetlands and grasslands, especially flooded lowlands in the sub-Sahelian savannahs during the rainy season (generally June-September). They also forage and nest along river banks, in rice and wet crop fields, and even in abandoned fields and other dry lands, although always close to wetlands. In the eastern portion of its range, the Black Crowned Crane typically inhabits larger freshwater marshes, wet meadows and fields, and open areas of emergent vegetation along the margins of ponds, lakes, and rivers. These landscapes often include acacias and other trees, in which the cranes will roost.
Black Crowned Cranes can be considered both year-round residents and local migrants, flocking—often in large numbers—during the dry (non-breeding) season and moving from large permanent wetlands to smaller temporary wetlands during the rainy season. Their circular platform nests are built of grasses and sedges within or along the edges of densely vegetated wetlands. The average clutch size is about 2.5 eggs/nest. The incubation period is 28-31 days. The fledging period is 60-100 days (Walkinshaw 1973, Johnsgard 1983).
Soon after the chicks hatch, the cranes move into nearby open upland/grassland areas where they forage on insects and the fresh tips of plants. During the dry season, they forage in upland areas, frequently near herds of domestic livestock where invertebrates occur in greater abundance. If the rains fail, or if nesting habitat is deleteriously affected by drainage or overgrazing, crane pairs will remain in flocks throughout the year. Daily and seasonal movements between feeding and roosting areas are thought to be extensive (perhaps up to several dozen kilometers), but there has been little research on this aspect of their life history (Urban 1981).
The principal threat facing the Black Crowned Crane is the loss, transformation, and degradation of habitat (Tréca in press). In the last two decades, wetlands and grasslands across the Sahel and Sudan Savanna regions, but especially in West Africa, have been devastated by natural forces and by the intensification of human land use. Drought and increased human pressures (especially overgrazing and destruction of tree cover) are widely considered to have contributed to the southward expansion of the Sahara Desert.1 Many seasonal and permanent wetlands (even those within protected areas) have been lost to desertification. At the same time, dramatic increases in human population have placed increased pressure on forest, range, and wetland resources (again, most severely in the west). In many areas, traditional forms of resource use have broken down, while intensified agricultural and industrial activities and large-scale development projects have been undertaken (Daddy and Ayeni in press). The environmental consequences, as they pertain to the Black Crowned Crane, are numerous and interrelated:
In some areas, the species is hunted for meat or captured and sold. Hunting traditions vary widely within the species’ range. In some areas, the eating of cranes is taboo. In Sudan, the species is not normally hunted and is not considered edible (Eljack in press), but it has been hunted during times of war-induced famine. In Chad, Nigeria, and other countries, crane hunting still occurs when the opportunity arises, but cranes no longer occur in sufficient numbers to sustain the practice. Live-trapping probably poses a more significant threat. Black Crowned Cranes are trapped and sold at a considerable profit domestically and also to dealers for foreign export. During the 1970s, the trade in cranes was a problem in Nigeria in particular; the trade has since collapsed due to the decline in the crane population.
Beyond these direct threats, Black Crowned Cranes are also affected throughout their range by ineffective law enforcement, insufficient penalties for illegal activities, inadequate policies and legislation to protect key habitats, and a lack of educational programs emphasizing the importance of wetlands. Finally, there is a basic lack of detailed information on, and little ongoing research concerning, the Black Crowned Crane, its status, and its habitat.
1In 1994, abundant rains occurred through many parts of the Sahel, resulting in flooding to levels that had not occurred since the 1960s.
2B. Tréca (pers. comm.) notes that, in Senegal, Black Crowned Cranes often use harvested (dry) rice fields for feeding and resting, even when people are in close proximity. He notes that "the expansin of rice fields is not always a threat for Black Crowned Cranes, as long as some wetlands [are] left nearby."
Legal and Cultural Protection
Black Crowned Cranes are fully protected by law in most of the countries where they occur, although this protection is often ineffective. All the West African countries have enacted legislation protecting cranes. In some countries, such as Burkina Faso, cranes also benefit from the high regard in which they are held under local cultural traditions. There is little hunting pressure on the species in the eastern part of its range.
International Agreements and Cooperation
About half of the range countries of the Black Crowned Crane are parties to the Ramsar Convention (see Table 3.2).
In 1994 it was proposed that the species be transferred from CITES Appendix II to Appendix I. The proposal was withdrawn, but may be resubmitted.
In February 1992, an International Conference on the Black Crowned Crane and Its Wetlands Habitat in West and Central Africa was held in Kano, Nigeria. This meeting focused attention on the decline of the Black Crowned Crane in western Africa and served to launch the Black Crowned Crane Working Group. The 1993 African Crane and Wetlands Training Workshop in Maun, Botswana provided an opportunity to exchange information and to assess the status of the species across its range (Urban in press). The proceedings of the workshop include many of the papers from the 1992 conference as well (Beilfuss et al. in press).
Protected Areas
Black Crowned Cranes use many of the national parks, reserves, and other protected areas that have been established within their range. These include: Djoudj and Nikolo-Koba National Parks in Senegal; Diawling and Banc d’Arguin National Parks in Mauritania; Parc du W in Nigeria; Mare aux Hippopotames International Biosphere Reserves, Arli and Kabore Tambi National Parks, and Pama Game Reserve in Burkina Faso; Penjari National Park in Benin: Waza and Kalamaloue National Parks in Cameroon; Chad Basin National Park in Nigeria; the Ouadi Rime-Ouadi Achim Reserve in Chad; Bamingui-Bangoran and Manovo-Gounda-Saint Floris National Parks in Central African Republic; Randam and Dinder National Parks in Sudan; and Abijatta Shala, Gambella, and Mago National Parks in Ethiopia. However, protected areas in the region are often constrained by limited budgets and ineffective administration.
Habitat Protection and Management
Little habitat management has been undertaken specifically to protect or restore Black Crowned Crane habitat. However, many of the sustainable agriculture, agroforestry, reforestation, and wetland conservation projects undertaken in West Africa offer direct and indirect benefits for Black Crowned Cranes. No sustained habitat restoration studies are underway.
Surveys/Censuses/Monitoring
Urban (in press) provides country-level estimates of Black Crowned Crane populations based on information presented at the 1993 African Crane and Wetlands Training Workshop. The species has been reliably surveyed only in limited portions of its range. Local surveys were undertaken on the Inner Niger River Delta in the mid-1980s (Skinner 1988). Surveys have been conducted in Senegal since 1989 (Tréca and Ndiaye in press). Brouwer and Mullié (in press) report recent and historical observations in Niger. Portions of Nigeria and Cameroon have also been surveyed in recent years. Black-crowned Cranes have also been counted during the African Waterfowl Census conducted by the International Waterfowl and Wetlands Research Bureau (IWRB) (Taylor and Rose 1994, Davies in press). One of the main objectives of the proposed West Africa Subregion Management Plan Project (see below) is to undertake coordinated aerial and ground surveys of the species in the western portion of its range. Few surveys of the Sudan Crowned Crane have been undertaken. Eljack (in press) reports a probable total of 5000-7000 at Lake Kundi in western Sudan in 1993.
Research
Of the African cranes, the Black Crowned Crane is the most in need of detailed field studies. This reflects not only its rapid decline and threatened status in the western portion of its range, but also the limited extent of previous research (Urban 1987). Johnsgard (1983) summarized available information on the two subspecies (treating them together with the two Grey Crowned Crane subspecies). No range-wide surveys of the population and very few ecological studies of the species and its habitats have been carried out. Mustafa and Durbunde (1992) provide an overview of the species range and numbers in West Africa, while Urban (in press) summarizes the current status of the species throughout its range.
Non-governmental Organizations
A Black Crowned Crane Coordinating Centre was established in 1992 to carry out the work of the Black Crowned Crane Working Group. It is based in Kano, Nigeria and is currently headed by Hadi Mustafa of Nigeria. The Working Group on African Cranes (WGAC) also promotes research and conservation projects involving the Black Crowned Crane. The WGAC’s newsletter, The Crowned Crane, serves as a medium for information exchange.
Other non-governmental organizations, working at the national level, have also supported crane and wetland conservation projects. Naturama, a private conservation group in Burkina Faso, has worked to develop public interest in crane conservation. In Nigeria, Pro-natura, a community-oriented conservation organization, assists in crane protection programs (P. Hall pers. comm.). Also in Nigeria, the Hadejia-Nguru Wetlands Conservation Project was established in 1987 through a partnership of the Nigerian government and the Royal Society for the Protection of Birds with support from the Nigerian Conservation Foundation, BirdLife International, the Finnish International Development Agency, the Finnish Association for Nature Conservation and the British Council (Nigerian Conservation Foundation 1989, Hollis et al. 1993).
West Africa Subregion Management Plan Project
The International Crane Foundation and the Wildlife Conservation Research Centre in Accra, Ghana, have outlined a West Africa Subregion Management Plan Project for the Black Crowned Crane. The goal of the project is to develop a management plan for the West African Crowned Crane that will be endorsed by the governments of all the range countries in West Africa. The specific objectives of the project are to: (1) establish (in partnership with the Black Crowned Crane Coordinating Centre) a survey coordinating center, and contact cooperating individuals and institutions in the region; (2) undertake a region-wide survey and conservation status assessment; and (3) develop and gain support for a management plan for the subspecies. Further information on this project is available through ICF.
Education and Training In Nigeria, public education programs have begun to draw attention to the precarious state of the species within the country. The Hadejia-Nguru Wetlands Project has undertaken a comprehensive “Keep the Wetlands Wet” campaign to promote conservation education and awareness (R. Beilfuss pers. comm.). Several Nigerian conservationists have received training with ICF and the United Kingdom Jersey Wildlife Preservation Trust (Mustafa and Durbunde 1992). ICF has also developed long-term plans to provide further training, both in-country and at ICF’s training center.
Propagation and Reintroduction
The GCAR for cranes estimated that 448 Black Crowned Cranes were maintained in captivity worldwide as of 1993. Of these 31 were reported as B. p. ceciliae, and 122 as B. p. pavonina; the remainder had no subspecies designation. Regional studbooks for the species are maintained in North America and in the United Kingdom (Table 1.5), and regional captive management plans exist in North America and Europe. The species is considered moderately difficult to maintain in captivity and does not breed predictably (Mirande et al. in press a).
As yet, no ongoing reintroduction program has been undertaken for the Black Crowned Crane. The potential for reintroduction in West Africa has been under discussion, and one experimental release took place in Nigeria in 1992 in connection with the West African Crowned Crane Conference (Taylor and Rose 1994, Daddy and Ayeni in press, Garba in press). Discussions have also been held concerning the development of a captive propagation program in Borno State, Nigeria that can be linked with a release program at the Chingurme-Duguma sector of Chad Basin National Park, which probably holds Nigeria’s last remaining population. The GCAR has recommended that a release program be initiated only after existing habitat conditions have been thoroughly assessed and sound habitat management plans implemented.
In addition to research connected with other conservation measures (national-level inventories of wetlands, population and habitat surveys, refinement of husbandry techniques, etc.), research on the Black Crowned Crane should focus on:
Community conservation projects are key to the long-term survival of the Black Crowned Crane and other wetland species in the species’ range. As specific projects are proposed, emphasis should be placed on involvement of various partners, including government agencies, local communities, non-governmental organizations, and schools and universities. The following activities should be given high priority: