Density Dependence of Reproductive Success in Grey Partridge Perdix perdix Populations in France: Management Implications

Elisabeth Bro ； Benoît Deldalle ； Manuel Massot ； François Reitz ； Slaheddine Selmi

《Wildlife Biology》 9卷2期 (2003/06) Pp. 93-102

並列摘要

The understanding of the demographic and ecological mechanisms of population regulation is central in applied ecology, in particular when it comes to managing harvested populations. We document the density dependence of the reproductive success in French grey partridge Perdix perdix populations. We used long-term data collected by the national network monitoring populations with a mere surveillance objective. We investigated a time series spanning 7-14 years for 85 replicate populations by a combined procedure of a regression of reproductive success against density for each population and a metaanalysis of the 85 regression slopes. We avoided two common statistical pitfalls by taking the autocorrelation in time series data into account and by using independent estimates of reproductive success and spring density. The relationship is statistically significant for 10% of the populations, and the meta-analysis of the 85 replicates displays a highly significant pattern (82.3% of the regression slopes being negative). Thus our results both support the existence of a density dependent reproductive success in the grey partridge and moderate the ubiquity of the phenomenon, despite a general trend. We tested whether density dependence occurred through competition or habitat heterogeneity by examining the relationship between the variability of per capita reproductive success and pair density. Our results support both alternative hypotheses depending upon the area of concern. In terms of population and habitat management our findings have implications for hunting interests. The best strategy to maximise the hunting quota when reproductive success is depressed with increased density recommends intermediate values of both pair density and reproductive success, which conciliates hunting interests and conservation objectives. To alleviate density dependence, habitat management should supply limited resources that are homogeneously distributed in space when density dependence operates through competition, and should improve habitat quality of the poorest patches when density dependence operates through habitat heterogeneity.

並列關鍵字

autoregression ； breeding density ； density dependence ； France ； grey partridge ； meta-analysis ； Perdix perdix ； reproductive success