This discussion was first published as part of the 2017 Red List update. At the time a decision regarding the status of several was pended, but to enable potential reassessment of these species as part of the 2018 Red List update this post remains open and the date of posting has been updated.
BirdLife Species factsheet for Northern Ground-hornbill: http://datazone.birdlife.org/species/factsheet/northern-ground-hornbill-bucorvus-abyssinicus
Northern Ground-hornbill, Bucorvus abyssinicus, is currently listed as Least Concern because it has not been thought to approach the threshold for Vulnerable under any criterion. The species is found in the Afrotropics in a band across from Senegal through to the Horn of Africa, and most commonly inhabits savannah and sub-desert as well as possibly being found in riparian habitats and woodland (Borrow and Demey 2014, Dowsett-Lemaire and Dowsett 2014, Kemp and Boesman 2017). The population size has not been quantified, but despite being sparsely distributed across its large range it is not thought to approach the threshold for Vulnerable based on population size, and would not approach the threshold under range size.
At the moment Northern Ground-hornbill is listed as having a stable population trend. There are, however, suggestions that the population may actually be in decline; Borrow and Demey (2014) state that the species is ‘probably declining’, and in Ghana the species has disappeared from areas where it had previously been found (Dowsett-Lemaire and Dowsett 2014). In fact, in Ghana it may be confined only to large wildlife reserves (F. Dowsett-Lemaire in litt. 2016). In Togo it may have disappeared from most faunal reserves as a result of illegal habitat clearance, and may only persist in Fazao-Malfakassa National Park although this site is now also under threat (F. Dowsett-Lemaire in litt. 2016). Forest reserves in Benin are also being invaded by farmers, and this could threaten populations of the species in this country too (F. Dowsett-Lemaire in litt. 2016). It is not only threatened by habitat conversion as in certain areas hunters may kill individuals and use their stuffed heads as disguises while stalking game, although it is treated as a totem species in some areas and so may be relatively protected in such places as a result of this (Kemp 1995, Kemp and Boesman 2017).
To qualify as Vulnerable a species must undergo, or be thought to undergo in the future, a decline of 30-49% over 3 generations. The generation length for this species is c.30 years so the period of time to look at is 90 years, which would encompass the suspected declines in places such as Ghana (see Dowsett-Lemaire and Dowsett 2014). As with its close relative the Southern Ground-hornbill, Bucorvus leadbeateri, (see BirdLife International 2017) it is difficult to accurately assess rates of population change – particularly projecting into the future – because the species is so long lived. To try to more accurately assess whether this species may warrant uplisting to a threatened category we request any further information particularly regarding rates of decline, and the status of this species elsewhere within its range.
BirdLife International (2017) Species factsheet: Bucorvus leadbeateri. Downloaded from http://www.birdlife.org on 06/01/2017.
Borrow, N.; Demey, R. 2014. Birds of Western Africa: Second Edition. Christopher Helm, London.
Dowsett-Lemaire, F.; Dowsett, R. J. 2014. The Birds of Ghana: An atlas and handbook. Tauraco Press, Liège, Belgium.
Kemp, A. (1995) The hornbills. Oxford: Oxford University Press (Bird Families of the World).
Kemp, A.C. & Boesman, P. (2017). Northern Ground-hornbill (Bucorvus abyssinicus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/55880 on 6 January 2017).