Wednesday 11 July 2012

THE CINEREOUS VULTURE IN EXTREMADURA. 1974-2009.


The minutes have recently been published of the International Cinereous Vulture (Aegypius monachus) Symposium held in Córdoba in 2004. It stands to reason, given the important Extremadura population of this species, that several of the published contents should refer to this region. The huge time-lag between the event itself and the publication of these minutes means that some of the articles have already fallen behind the times. Luckily, some of the submitted papers have been updated. This is the case of an article dealing with the Extremadura Cinereous Vulture population, with additional figures from 2009 phased in (Caldera, 2012). Tapping into this data, we have compiled the published figures on this species in Extremadura, from the first estimates of 1974 up to the 2009 count. The results are displayed in the following table (click on it to open it up).


In more intuitive form the following graph shows clearly the upward trend in Extremadura's Cinereous Vulture population, although the population of the early years was greatly underestimated. The figures are more trustworthy from 1990 onwards. We also show the trend over time of the two biggest colonies, Sierra de San Pedro and Monfragüe. Bear in mind here that the figures refer to pairs that start breeding, so the actual population, including non-breeding birds and those undetected due to methodological reasons, is higher. In 2006 the breeding population was 829 pairs in Extremadura whereas the actual population is estimated to have been over 1200 pairs (De la Puente et al., 2007).


The lower map below shows the distribution (modified from Costillo, 2004). To match the colonies with the figures of the top table, the three northern colonies, marked with in green (Sierra de Gata), light blue (Las Hurdes) and dark blue circles (Granadilla) are considered to be a single group. In the southwest lie the big colony of Sierra de San Pedro (grey circles) and Tajo-Salor (dark green). In the centre-east of Cáceres lie Monfragüe (yellow, as from 2004 it has spread westwards) and Los Ibores (pink), which should really be taken to be a single unit. In the northeast of Badajoz are the two small clusters of Cíjara (red) and La Siberia (white; dying out in 2012). The original map dates from 2004 so it does not include the new expansion areas, which have been added on with a larger coloured circle: Canchos de Ramiro (red), Cañaveral (light green), Montáchez (blue) and Villuercas (orange). This latter cluster does not figure in any official count but birds are known to have nested there since 2007 (one certain pair and another probable), as recorded in the Extremadura Ornithological Yearbook (Anuario Ornitológico de Extremadura: Herrera et al., 2011).


Sources: 
- Caldera J. 2012. El buitre negro Aegypius monachus en Extremadura (España), pp. 38-40. In: Dobado, P. M. and Arenas, R. (coords). El Buitre Negro: Situación, Conservación y Estudios. Actas del Primer Simposium Internacional sobre el Buitre Negro Aegypius monachus (Córdoba, Spain, 21-23 October 2004). Consejería de Medio Ambiente de la Junta de Andalucía. 
- Costillo, E. 2004. El buitre negro en Extremadura. Doctoral Thesis . Universidad de Extremadura. 
- De la Puente, J., Moreno-Opo, R. and del Moral, J. C. 2007. El Buitre Negro en España: Censo Nacional (2006). SEO/BirdLife. Madrid. 
- Dobado, P. M. and Arenas, R. (coords). 2012. El Buitre Negro: Situación, Conservación y Estudios. Actas del Primer Simposium Internacional sobre el Buitre Negro Aegypius monachus (Córdoba, España, 21-23 October 2004). Consejería de Medio Ambiente de la Junta de Andalucía. 
- Herrera, J. A., Cerezo, J. and N. Baeza. 2011. Buitre negro Aegypius monachus. In, Prieta, J. and Mayordomo, S. Aves de Extremadura, vol. 4. 2004-2008. SEO-Cáceres. Plasencia.
- Rodríguez, Á. 2012. El buitre negro Aegypius monachus en el Parque Nacional de Monfragüe (Cáceres, Extremadura, España), pp. 223-226. In: Dobado, P. M. and Arenas, R. (coords). El Buitre Negro: Situación, Conservación y Estudios. Actas del Primer Simposium Internacional sobre el Buitre Negro Aegypius monachus (Córdoba, España, 21-23 October 2004). Consejería de Medio Ambiente de la Junta de Andalucía.