Prior to del Hoyo and Collar (2016), the Iberian (Southern) Grey Shrike, Lanius meridionalis, was treated by BirdLife as a subspecies of L. excubitor, and by Handbook of the Birds of the World as a separate species that included Iberian, North Africa, Middle Eastern and Asian populations (del Hoyo et al. 2008). The newly recognised species is restricted to the Iberian Peninsula and southern France. Data regarding this species was collected as part of the European Red List of Birds (BirdLife International 2015), with population figures estimated at 372,150-656,150 pairs, or 744,300-1,312,300 mature individuals. Therefore, given its reasonably large range and such high population size estimates, it would not approach the threshold for Vulnerable under criteria B, C or D.
This species may, however, be under threat from several factors. Intensification of agriculture means that its habitat and prey availability are declining (Tucker and Heath 1994). At the same time, a reduction of certain types of agriculture can also have negative impacts on the species, with the removal of sheep potentially leading to the invasion of shrub, and thus creating unsuitable habitat for this species (Tucker and Heath 1994). Development of industry as well as road building may impact upon this species too; and disturbance from humans, cars and dogs can potentially increase predation risk by attracting the attention of nest-predators such as corvids (Tucker and Heath 1994). Such threats mean this species has undergone and likely continues to undergo rapid population declines (BirdLife International 2015).
The majority of the population is found in Spain, where it underwent a decline of 57% between 1998 and 2012. The appropriate period of time to investigate rate of decline is 3 generations or 10 years (whichever is the longer) and in this species this would be 3 generations, which is currently estimated at c. 12 years. Combining population size and trend estimates from across its range indicates that the species has undergone a decline of between 49% and 52% over 3 generations. Therefore, the rate of decline for this species falls at the borderline of and Vulnerable (30-49% decline) and Endangered (50-79% decline). For now, it is proposed that this species be listed as Vulnerable under criteria A2abc+3bc+4abc. Should its rate of decline accelerate in future, then it could easily qualify for further uplisting.
Any comments or further information would be welcomed.
BirdLife International (2015) European Red List of Birds. Luxembourg: Office for Official Publications of the European Communities.
del Hoyo, J.; Collar, N. J. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions BirdLife International.
del Hoyo, J., Elliott, A. and Christie, D. (2008) Handbook of the Birds of the World, vol. 13: Penduline-tits to Shrikes. Barcelona, Spain: Lynx Edicions.
Tucker, G. M.; Heath, M. F. 1994. Birds in Europe: their conservation status. BirdLife International (BirdLife Conservation series no. 3). Cambridge, U.K.