Initial deadline for comments: 31 January 2012 [note that this has been moved back by about two months].
Grey Crowned-crane Balearica regulorum is a widespread resident of eastern and southern Africa, inhabiting wetlands and associated habitats. It is currently listed as Vulnerable under criteria A2c,d; A4c,d, because it is thought to have undergone a rapid population reduction over the past three generations (30-49% over 45 years). This decline is attributed to the conversion and degradation of wetlands for cultivation and livestock farming and the illegal removal of birds and eggs from the wild for food, traditional uses, domestication and illegal export (Beilfuss et al. 2007). A recently published study, involving a nationwide newspaper survey and visits to wetlands, found that the harassment and trapping of cranes (Balearica spp.) was common in Uganda during breeding (Olupot et al. 2009). Threats to cranes were reported at 25% of the 224 sites visited, with the commonest being nest destruction (56%), followed by trapping (16%), killing of cranes with stones or sticks (11%), removal of eggs (9%), and poisoning (4%), amongst other less frequent threats (Olupot et al. 2009).
When this species was uplisted from Least Concern to Vulnerable in the 2009 Red List update, there was some evidence to suggest that declines may have exceeded a rate of 50% during the past three generations or 45 years (Beilfuss et al. 2007), but data were regarded as patchy and an overall decline of 30-49% was considered a more reasonable estimate.
Recently collated data indicate that the species may have declined by more than 70% in Uganda since the early 1970s (National Biodiversity Data Bank in prep.) A similar decline is suspected to have taken place in Kenya, although there are no data to corroborate this (K. Morrison in litt. 2011). Existing estimates suggest that a decline of c.30-40% occurred in Kenya between 1994 and 2004 (Beilfuss et al. 2007). These data are particularly important given that Uganda and Kenya are thought to hold c.66-70% of the species’s entire population (Beilfuss et al. 2007). Provisional data from the Tanzania Bird Atlas project indicate that, when some control is applied for variation in recording effort, the species has declined at least since the 1980s (Morrison et al. 2007).
Overall estimates suggest that the species’s global population has declined from over 100,000 individuals in 1985 to 50,000-64,000 individuals in 2004 (Beilfuss et al. 2007). This implies that the species may have declined by over 50% in 19 years, and when these data are extrapolated to a period of 45 years in the past (1967-2012) or past and future (1985-2030), assuming an exponential trend, the calculated rate of decline is c.65-80%. Such a rate of decline would qualify the species for uplisting to Endangered under criteria A2a,c,d; A4a,c,d, on the basis that a decline of 50-79% is estimated and projected to occur over 45 years, assuming that the relevant threatening events have been prevalent at least since the late 1960s and that there is no future improvement on existing conservation efforts.
Comments are invited on this potential category change and additional information is requested, especially for parts of the species’s range for which more reliable data have previously been lacking.
Beilfuss, R., Dodman, T. and Urban, E. K. (2007) The status of cranes in Africa in 2005. Ostrich 78: 175-184.
Morrison, K., Beall, F., Friedmann, Y., Gichuki, C., Gichuki, N., Jordan, M., Kaita, M., Ndang’ang’a, P. and Muheebwa, J. (Eds) (2007) African Crane Trade Project: Trade Mitigation Planning Workshop. Workshop Report. Conservation Breeding Specialist Group (SSC/IUCN)/CBSG Southern Africa. International Crane Foundation/Endangered Wildlife Trust Partnership, Johannesburg.
Olupot, W., Mugabe, H. and Plumptre, A. J. (2009) Species conservation on human-dominated landscapes: the case of crowned crane breeding and distribution outside protected areas in Uganda. Afr. J. Ecol. 48: 119-125.