Using an energetic cost–benefit approach to identify ecological traps: the case of the African wild dog

Abstract

AbstractIn a natural environment, there are high‐quality habitats that produce a surplus of animals (sources), facilitating migration into low‐quality habitats in which mortality exceeds natality (sinks). Human alterations can increase the attractiveness of a low‐quality habitat and/or decrease the suitability of a high‐quality habitat, herewith creating an ecological trap. In an ecological trap, animals prefer to stay in habitats where mortality exceeds natality, which can result in extirpation of a population. It is important to distinguish ecological traps from sinks; however, relative population densities do not necessarily give reliable information. In order to identify ecological traps and set appropriate conservation priorities, it is necessary to gain insight into the relationship between habitat preference, quality and suitability. In this study, we used African wild dog hunt data and energetic cost–benefit analysis to determine whether the preferred habitat outside Hwange National Park (HNP) serves as an ecological trap. This analysis enabled us to take several ecological factors into account while assessing habitat quality. Although outside HNP anthropogenic mortality exceeded natality, per capita energetic intake was higher. This indicates that the habitat outside HNP serves as an ecological trap where human alterations have decreased the suitability of the high quality habitat. In order to ensure the recovery of the African wild dog population, conservation efforts should therefore focus on improving the suitability of the habitat outside HNP. This study shows that an energetic cost–benefit analysis can assist with identifying ecological traps and setting conservation priorities. Moreover, in cases of social territorial species, the cost–benefit analysis may also help to identify ecological traps before source populations are depleted, thus increasing the likelihood of population recovery.