Great Bustard, Otis tarda, is currently listed as Vulnerable under criteria A2cd+3cd+4cd (see BirdLife International 2017) as it is undergoing rapid population declines. It has a wide, but fragmented distribution across Eurasia, with a small, declining population present in Morocco. Most recent population estimates place the global population in the range 43,847-56,695 individuals (Alonso 2014).
Historically the species underwent large declines and became extinct in several former range states, including France, Greece, Sweden and United Kingdom (see Collar and Garcia 2017). Declines have continued in several countries as a result of land-use changes and agricultural intensification (Nagy 2009, Chan and Goroshko 1998, S. Nagy in litt. 1999, 2007, M. Kessler in litt. 2016), hunting (Chan and Goroshko 1998, Karakaş and Akarsu 2009, Y. Andryucshenko in litt. 1999, P. Goriup in litt. 2007, M. Kessler in litt. 2012, 2016, M. M. Karataş in litt. 2016), and collisions with power lines/wind turbines (Nagy 2009, J. C. Alonso in litt. 2007, S. Nagy in litt. 2012, M. Kessler in litt. 2012). These declines have been predominantly in parts of eastern and central Europe, Morocco, as well as throughout the eastern part of the global distribution (Chan and Goroshko 1998, Barati and Amerifar 2008, Palacín and Alonso 2008, BirdLife International 2015, Alonso et al. 2016, M. Karataş in litt. 2016). However, in other areas (notably Hungary, Germany, Austria and the Iberian Peninsula) the population has been increasing or potentially stable since the 1990s (see Nagy 2009, BirdLife International 2015) as a result of conservation measures and a hunting ban established in 1980 (Alonso 2014, Collar and Garcia 2017).
This information led to its regional listing as Least Concern in both the EU and Europe in the European Red List of Birds (BirdLife International 2015). Given that Europe holds such a large proportion of the global population (see Alonso 2014), and declines over the past 20-30 years have not been significant (see Alonso 2014, Palacín and Alonso 2008, Alonso and Palacín 2010), it appears unlikely that the species’s global population has declined by >30% (or approached a decline of 30%) over the past 3 generations (30 years). Thus it would no longer meet or approach the threshold for Vulnerable under criterion A2+4. Based on the data it would also appear unlikely to remain as Vulnerable under criterion A3. As Spain alone contains c.2/3 of the global population, and the population there is said to be increasing, almost the entirety of the rest of the global population would need to disappear and the population remain stable in Spain over the next 30 years for the global assessment to remain as Vulnerable under criterion A3.
While declines in other countries are worrying, and the species’s Area of Occupancy may continue to decline as a result of the loss of small populations (S. Nagy in litt. 2012), based on the available data it is now unlikely that the species meets the IUCN threshold values for the species to qualify as Vulnerable any more. Therefore, the species may warrant downlisting. As stated above, the species does not appear to approach the threshold for Vulnerable under criteria A2+4. However, given how the recent turn around in this species’s fortunes may depend on continued conservation measures (such as a limit/ban of hunting in certain countries), and declines are likely to continue into the future in several range states, it is conservatively suggested that this species be listed as Near Threatened under criterion A3cd, as it is suspected that there is the potential for the species to decline at 20-29% in the future.
We welcome any further information or comments regarding this proposed downlisting.
Alonso, J. C. 2014. The Great Bustard: past, present and future of a globally threatened species. Ornis Hungarica 22(2): 1-13.
Alonso, J. C.; Palacín, C.; Onrubia, A.; Aboulouafae, R.; Amezian, M.; Essougrati, A. I.; El Khamlichi, R.; Noaman, M. 2016. Alarming decline and range reduction of the highly threatened Great Bustard Otis tarda in Morocco. Ostrich 87: 277-280
Barati, A.; Amerifar, A. A. 2008. On the status of the Great Bustard, Otis tarda Linnaeus, 1758 (Aves: Otididae) in Kurdistan Province, Iran. Zoology in the Middle East: 41-48.
BirdLife International. 2015. European Red List of Birds. Office for Official Publications of the European Communities, Luxembourg.
BirdLife International. 2017. Species factsheet: Otis tarda. Downloaded from http://www.birdlife.org on 11/04/2017.
Chan, S.; Goroshko, O. 1998. Action plan for the conservation of the Great Bustard. BirdLife Asia, Tokyo.
Collar, N.; Garcia, E.F.J. 2017. Great Bustard (Otis tarda). 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/53712 on 11 April 2017).
Karakaş, R. and Akarsu, F. 2009. Recent status and distribution of the Great Bustard, Otis tarda, in Turkey. Zoology in the Middle East 48: 25-34.
Nagy, S. 2009. International single species action plan for the Western Palearctic population of Great Bustard, Otis tarda tarda. BirdLife International on behalf of the European Commission.
Palacín, C.; Alonson, J. C. 2008. An updated estimate of the world status and population trends of the Great Bustard Otis tarda. Ardeola 55(1): 13-25.