Justification
Habitat destruction and persecution are estimated to have caused very rapid population declines in South Africa and there are anecdotal reports that they have caused declines in other range countries. There is a high probability that such threats and subsequent declines will continue into the future, and as such this qualifies as Vulnerable. Should more accurate trend data become available further reassessment may be required in the future.
Taxonomic source(s)
Dowsett, R. J.; Forbes-Watson, A. D. 1993. Checklist of birds of the Afrotropical and Malagasy regions. Tauraco Press, Li
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.
Taxonomic note
Use of the specific name leadbeateri (Sibley and Monroe, 1990, 1993) is accepted following the reasons given in Browning (1992).
Synonym(s)
Bucorvus cafer BirdLife International (1994, 2000, 2004, 2008), Bucorvus leadbeateri Sibley and Monroe (1990, 1993), Bucorvus leadbeateri leadbeateri Sibley and Monroe (1990, 1993)
Distribution and populationBucorvus leadbeateri is found in southern Africa, ranging from southern
Kenya and
Burundi, south-west to
Angola and northern
Namibia, and south to
Botswana and eastern
South Africa. It is described as widespread and fairly common, and the population in South Africa in 1992 has been estimated at c.1,400 mature individuals - perhaps a 50% decline on historical population numbers (Kemp and Webster
in litt. 2008)
. Although data for other range countries is lacking, several threats are also thought to be causing population declines in Kenya (S. Thomsett
in litt. 2010)
, Botswana (S. Tyler
in litt. 2010)
and Zambia (R. Tether, P. Leonard and
L. Roxburgh
in litt. 2010)
, though rates of decline in Zambia are thought to be slower than elsewhere (L. Roxburgh
in litt. 2010)
. In Botswana it is still frequent in the Okavango Delta and Chobe areas, where it occurs at higher densities than it averages in South Africa, but is likely to be declining away from protected areas (S. Tyler
in litt. 2012).
Population justificationThe global population size has not been quantified, but the species is reported to be widespread and common but sparse.
Trend justificationAn assessment of the species's status in South Africa (Kemp and Webster
in litt. 2008) estimated a 20% loss in the area of suitable habitat within the species's national range in the past 15 years. If this figure is used to project declines into the future, this equates to a population decline of 74% over 94 years (three generations). Although declines are also suspected in other range countries (S. Thomsett and S. Tyler
in litt. 2010), there are not thought to be significant declines in Zambia, which may be a stronghold of the species (P. Leonard and
L. Roxburgh
in litt. 2010). As such, and given that data is lacking and that it is difficult to accurately project future declines for such a long-lived species, a decline of 30-49% is projected over 94 years (three generations).
EcologyBehaviour It lives in groups of 2-8 members, rarely 11, and is a co-operative breeder, with the dominant pair assisted by adult and immature helpers to defend a territory. Laying occurs in large cavities in trees or cliffs, mainly from September to December, with a clutch of 1-3 (usually 2) eggs, although only one survives to fledging (del Hoyo
et al. 2001; Kemp and Webster
in litt. 2008)
. One study in South Africa showed that a family group produced on average only one fledgling every nine years, although birds in the Okavango Delta appear to breed more frequently (del Hoyo
et al. 2001; S. Tyler
in litt. 2010).
Habitat It inhabits woodland and savanna, also frequenting grassland adjoining patches of forest up to 3,000 m in parts of its range in eastern Africa.
Diet Its diet is mainly made up of arthropods, and, especially during the dry season, snails, frogs and toads, and sometimes larger prey such as snakes, lizards, rats, hares, squirrels or tortoises. It will on occasion feed on carrion, taking scraps and associated insects. Fruits and seeds are also recorded in its diet (del Hoyo
et al. 2001)
.
ThreatsA major threat to the species is loss of nesting habitat due to clearance for small-scale use, agriculture, and because of fires, and perhaps because of the actions of African elephants
Loxodonta africana in Botswana and South Africa (del Hoyo
et al. 2001; S. Thomsett
, S. Tyler, R. Tether, P. Leonard and
L. Roxburgh
in litt. 2010; K. Morrison and Y. Friedmann
in litt. 2005)
. Widespread livestock grazing has also lead to the erosion of suitable grassland in Kenya, with perhaps only 10% of suitable habitat remaining in the country (S. Thomsett
in litt. 2010)
. Although cultural beliefs offered some protection in the past in Kenya, recent generations tend not to hold such values, and the species may be directly persecuted as a result (S. Thomsett
in litt. 2010)
. Persecution also occurs directly as the species breaks window panes by attacking its own reflection in glass, indirectly by consuming poisoned bait, and it is sometimes killed as a supersitious token measure against drought (del Hoyo
et al. 2001; K. Morrison and Y. Friedmann
in litt. 2005)
. Collisions with powerlines may also be a threat in South Africa (K. Morrison and Y. Friedmann
in litt. 2005)
. Such threats are exacerbated by the slow reproductive rate and maturation, longevity and social structure of the species (S. Thomsett
in litt. 2010)
.
Conservation actions underwayIt may still be protected by tribal lore in many areas, and occurs in several reserves and at least seven national parks (del Hoyo
et al. 2001). There is extensive conservation work being carried out in South Africa, including a re-introduction programme, research into several different areas (population dynamics, tracking, and the feasibility of supplementary feeding, multiple clutching, group supplementation and artificial nest-site provision), and public awareness campaigns (A. Turner
in litt. 2009). From 2000-2008 the Mabula Project attempted 13 soft and hard releases and re- introductions of individuals, and a re-introduced female fledged a chick in 2008 in the Mabula Game Reserve (A. Turner
in litt. 2009, 2011).
Conservation actions proposedConduct population surveys and establish monitoring to assess population trends. Begin awareness campaigns to prevent persecution. Identify key strongholds of the species and prevent further habitat degradation in these areas. Continue to research the effectiveness of artificial nest-sites.
References
del Hoyo, J.; Elliott, A.; Sargatal, J. 2001. Handbook of the Birds of the World, vol. 6: Mousebirds to Hornbills. Lynx Edicions, Barcelona, Spain.
Further web sources of information
Hear sounds for this species from xeno-canto, the community database of shared bird sounds from around the world.
View photos and videos, and hear sounds of this species from the Internet Bird Collection
Text account compilers
Butchart, S., Calvert, R., Ekstrom, J., Symes, A.
Contributors
Leonard, P., Roxburgh, L., Tether, R., Thomsett, S., Turner, A., Tyler, S.
IUCN Red List evaluators
Butchart, S., Taylor, J.
Recommended citation
BirdLife International (2013) Species factsheet: Bucorvus leadbeateri. Downloaded from
http://www.birdlife.org on 25/05/2013.
Recommended citation for factsheets for more than one species: BirdLife International (2013) IUCN Red List for birds. Downloaded from
http://www.birdlife.org on 25/05/2013.
This information is based upon, and updates, the information published in BirdLife International (2000)
Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004)
Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.
To provide new information to update this factsheet or to correct any errors, please email BirdLife
To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.
Additional resources for this species
