Caucasian Grouse Lyrurus mlokosiewiczi is endemic to the Greater and Lesser Caucasus mountains. It is currently listed as Near Threatened, because when last assessed it was projected to undergo a moderately rapid population decline owing to road construction for tourism development, through increased hunting, grazing and wood cutting, as well as habitat fragmentation.
Globally, it has a relatively large range (>80,000 km2), and hence does not approach the thresholds for Vulnerable under the range size criteria (B and D2). Its population size is also reasonably large, comprising between c. 30,000–63,000 individuals based on habitat modelling (Gavashelishvili & Javakhishvili 2010) and c. 11,500–25,500 lekking males (i.e. c. 34,500–76,500 individuals) based on national estimates (BirdLife International 2015), and hence does not approach the thresholds for Vulnerable under the population size criteria (C and D1). Therefore, the only potentially relevant criterion is A, which relates to reductions in population size. Until recently, the population was projected to undergo a moderately rapid decline, at a rate approaching the threshold for listing as Vulnerable under criterion A (at least a 30% decline over ten years or three generations, whichever is longer).
New data collated from across Europe for the European Red List of Birds (BirdLife International 2015) suggest that the species may not be declining as steeply as projected, although there are gaps in the data. These data, provided by BirdLife Partners and other leading national ornithologists, suggest that the Russian population has been stable since at least 2000, while the Turkish population may have declined by only 10–19% since 1990. No recent trend data were available for Georgia, Armenia or Azerbaijan, but considering those reported for the previous European assessment (BirdLife International 2004), it seems that overall the European population may have only declined by <20% over the last three generations (19.2 years, based on a generation length estimated by BirdLife to be 6.4 years). Consequently, the species is now classified as Least Concern at European level (BirdLife International 2015).
Based on its distribution, Europe holds >95% of the global range of this species, so its trend in this region is of global significance. The only other population is in NW Iran, which has recently been the subject of several studies (e.g. Habibzadeh et al. 2013, Darvishi et al. 2015), and is thought to have increased in size from 215 individuals in 2001 to 350 individuals in 2009 (Khaleghizadeh et al. 2011).
Overall, therefore, the limited information available implies that the species is not declining sufficiently rapidly to be listed as Near Threatened, and hence should be reclassified as Least Concern.
Comments on this proposal are welcome, along with any data regarding population trends elsewhere in the Caucasus (especially in Georgia), and any current information about the threats affecting this species.
BirdLife International (2004) Birds in Europe: population estimates, trends and conservation status. Cambridge, UK: BirdLife International (Conservation Series No. 12).
BirdLife International (2015) European Red List of Birds. Luxembourg: Office for Official Publications of the European Communities. http://www.birdlife.org/datazone/info/euroredlist
Darvishi, A., Fakheran, S., & Soffianian, A. (2015). Monitoring landscape changes in Caucasian black grouse (Tetrao mlokosiewiczi) habitat in Iran during the last two decades. Environmental monitoring and assessment, 187(7), 1-13.
Gavashelishvili, A. & Javakhishvili, Z. (2010) Combining radio-telemetry and random observations to model the habitat of Near Threatened Caucasian grouse Tetrao mlokosiewiczi.” Oryx 44: 491-500.
Habibzadeh, N., Karami, M., Alavipanah, S. K., & Riazi, B. (2013). Landscape Requirements of Caucasian Grouse (Lyrurus mlokosiewiczi) in Arasbaran Region, East Azerbaijan, Iran. The Wilson Journal of Ornithology, 125(1), 140-149.
Khaleghizadeh, A., Scott, D. A., Tohidifar, M., Babak, S., Musavi, M. G., Sehhatisabet, M. E., & Eskandari, F. (2011). Rare birds in Iran in 1980−2010. Podoces 6: 1-48. www.wesca.net