2024-03-29T06:19:34Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/649302020-12-10T07:27:10Zcom_10261_13com_10261_8com_10261_108col_10261_266col_10261_361
Density-dependent productivity depression in Pyrenean Bearded Vultures: Implications for conservation
Carrete, Martina
Donázar, José A.
Margalida, Antoni
Fundación BBVA
The main objective of many conservation programs is to increase population size by improving a species' survival and reproduction. However, density dependence of demographic parameters may confound this approach. In this study we used a 25-year data set on Bearded Vultures (Gypaetus barbatus) in Spain to evaluate the consequences of population growth on reproductive performance. Unlike its coefficient of variation (CV), mean annual productivity decreased with increasing population size. After controlling for territorial heterogeneity, productivity also was negatively related to the distance to the nearest conspecific breeding pair and to supplementary feeding points where floaters congregate. These results suggest that vulture populations are regulated as posited by the site-dependency hypothesis: as the population increases, average productivity decreases because progressively poorer territories are used. The combined effects of the shrinkage of territories and the presence of floaters around supplementary feeding points seem to be the main causes of productivity decline and are therefore the main determinants of territory quality. This has conservation implications, especially concerning the role of supplementary feeding points. Supplementary feeding should be reviewed given that its usefulness in reducing preadult mortality has not yet been proved and its effect on productivity, as our results suggest, is negative. © 2006 by the Ecological Society of America.
2013-01-24T09:46:58Z
2013-01-24T09:46:58Z
2006
2013-01-24T09:46:58Z
artículo
Ecological Applications 16(5): 1674-1682 (2006)
http://hdl.handle.net/10261/64930
10.1890/1051-0761(2006)016[1674:DPDIPB]2.0.CO;2
http://dx.doi.org/10.13039/100007406
eng
Publisher's version
https://doi.org/10.1890/1051-0761(2006)016[1674:DPDIPB]2.0.CO;2
openAccess
Ecological Society of America