Age and sex ratios in a high-density wild red-legged partridge population
MetadataShow full item record
The dynamics of a wild red-legged partridge population were examined over a 14-year period in Spain to identify patterns in age and sex ratios in relation to weather parameters, and to assess the importance of these parameters in population dynamics and management. The results gave age ratios of 1.07 (but 2.13 in July counts), juvenile sex ratios of 1.01 and adult sex ratios of 1.47. Overall, 12% more females were hatched and female juvenile mortality was 7.3% higher than in males. Sex differential mortality explains the 19.2% deficit in adult females, which are more heavily predated than males during the breeding period. Accordingly, age ratios are dependent on sex ratios and both are density dependent. Over time, ratios and density changes appear to be influenced by weather and management. When the habitat is well conserved, partridge population dynamics can be explained by a causal chain: weather operates on net primary production, thereby affecting partridge reproduction and predation and, as a result, age and sex ratios in the October population. A reduction in the impact of predation (i.e. the effects of ground predators on eggs, chicks and breeding females) is the key factor to improve the conservation of partridge populations and associated biological processes.
Is part ofPlos One, 2016, vol. 11, núm. 8, e0159765
European research projects
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Nadal García, Jesús; Ponz Gan, Mª Carolina; Margalida, Antoni (Nature Publishing Group, 2018)Wild birds differ in size according to their age and sex, adult birds being larger than juveniles. In the galliforms, males are larger than females, in contrast to some groups, such as the raptors, in which the females are ...
Nadal García, Jesús; Ponz Gan, Mª Carolina; Margalida, Antoni (BMC, 2018)Background Predation is one of the most important natural selection forces. Prey species can optimize feeding behavior and escape from predators based on mobility conditioned by body proportions. With age, mobility ...
The end of primary moult as an indicator of global warming effects in the Red-legged Partridge Alectoris rufa, a medium sized, sedentary species Nadal García, Jesús; Ponz Gan, Mª Carolina; Margalida, Antoni (Elsevier, 2021-01-04)Global warming affects ecosystem services, communities and populations, influencing the physiology, behaviour or environment of living beings, and hence impacts its survival or breeding. Identifying species susceptibility ...