Tuesday 30 August 2011

GREAT BUSTARDS IN THE WORLD

Great Bustard (Otis tarda). Male at the height of its breeding display. Photograph by Carlos Palacín, one of the authors of the work quoted in the text (taken from Proyecto Avutarda).

The first volume of the scientific review Chinese Birds regales us with an update of the worldwide status of the Great Bustard (Otis tarda), written by two Spanish experts (Alonso and Palacín, 2010). The worldwide population is estimated to be 50,000 birds (44,100-57,000), most of them in Spain (57-70%). Europe boasts the biggest populations, Spain being followed by European Russia (10,000), Portugal (1900) and Hungary (1500). Much less is known about the Asian populations but the most important sites seem to be China, the central steppes and Turkey. The good news is that there is no sign of a global decline in the last decade, largely thanks to the growth in Iberia's population. The Asian information is less trustworthy with an uncertain trend in many areas and a slight decline in others. Of particular interest is the small nearby population in Morocco (100 birds), as well as those of Austria (200) and Germany (115), both on the increase.

The bulk of Iberia's population lives in the region of Castilla y León, where the most recent counts point to new increases. As for Extremadura, there are no recently published figures; the most recent information to hand shows the following: 5176 birds counted in January 2003 and 2852 birds in spring 2002 (Corbacho et al., 2005). Nonetheless, Alonso et al. (2005) consider these Extremadura counts to be imprecise, especially due to the huge 2500-bird difference between the spring and winter figures (2000 in the Province of Badajoz). According to them such a gap should not exist because it has never been recorded in other regions. Alonso et al. (2005), based above all on the January count, thus estimate the Extremadura population to be 5500-6500 birds.

Population trend of the Great Bustard (Otis tarda) worldwide and in Spain, maximum estimates between 1985 and 2010. The earlier estimates are rough and ready figures that may well understate the true population.

Country breakdown of the Great Bustard population (Otis tarda) in 2010.

Sources:
- Alonso, J. C. and Palacín, C. 2010. The world status and population trends of the Great Bustard (Otis tarda): 2010 update. Chinese Birds 1:141-147 [download in PDF].
- Alonso, J. C., Palacín, C. and Martín, C. A. 2005. La avutarda común en la península Ibérica: población actual y método de censo. SEO/BirdLife. Madrid [download in PDF].
- Corbacho, C., Fernández, A., Costillo, E., Lozano, L., Acedo, F. and Gil, A. 2005. La avutarda común en Extremadura: distribución, población y tendencias. In: Alonso, J. C., Palacín, C. and Martín, C. A. La avutarda común en la península Ibérica: población actual y método de censo. SEO/BirdLife. Madrid.