This discussion was first published as part of the 2013 Red List update, but remains open for comment to enable reassessment in 2014.
Grauer’s Cuckooshrike Coracina graueri is known from the Democratic Republic of Congo where it is restricted to the east of the country from Djugu and Mongbwalu (west of Lake Albert) to south of Lutunguru (west of Lake Edward), also being found on Mt Kahuzi and south to Kitongo, and it has recently been recorded from Uganda. It is currently listed as Near Threatened under B1ab(i,ii,iii,v) because it was thought to have a moderately small population, likely to be in decline owing to habitat destruction and degradation within its range. However, recent mapping of this species’s range suggests that it is larger than previously thought, with an Extent of Occurrence (EOO) of 31,900km2. As a result, it no longer approaches the thresholds for Vulnerable under the range size criterion and could warrant downlisting to Least Concern.
Nevertheless, the global population size has not been quantified, but the species is described as extremely local and uncommon within its small range (del Hoyo et al. 2005), and is suspected to be in decline owing to habitat destruction (del Hoyo et al. 2005). If there is evidence to suggest that the population of this species is likely to number fewer than 10,000 mature individuals, all subpopulations are fewer than 1,000 mature individuals and it is confirmed to be in continuing decline, this species would qualify as Vulnerable under criterion C2a(i) of the IUCN Red List. If it approaches, but does not meet, these population thresholds it should be maintained as Near Threatened but listed under criterion C2a(i). If the population size and size of largest subpopulation structure do not approach these thresholds, and the population is not suspected to be declining at a rate of ≥25% over three generations (14 years) it should be downlisted to Least Concern.
Further information is requested on this species’s population size, trends, distribution and size of the largest subpopulation. Additional comments on the proposed reassessment are also welcome.
del Hoyo, J., Elliott, A. and Christie, D. (2005) Handbook of the Birds of the World, vol. 10: Cuckoo-shrikes to Thrushes. Lynx Edicions: Barcelona, Spain.
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