In this post Susan Cheyne, who is taking part in our Associate Editor mentoring opportunity discusses a paper she recently handled by Paula Perrig and colleagues ‘Puma predation subsidizes an obligate scavenger in the high Andes

Of great interest in understanding biological systems is the often complex interplay between animals occupying different niches. Past studies involving ecological indicators of ecosystem function have selected individual indicator species based on 1) ease of surveying 2) ease of identifying and 3) life history traits e.g. short-lived with the assumption that short-lived species will respond faster to change and 4) species which range over a relatively small geographical distance.

Management of habitats and ecosystems often focusses on these one or few umbrella or keystone species, with the assumption that preserving the habitat for these species will have a knock-on effect on others. Equally resources are often focussed on understanding the behavioural ecology of these few species as a proxy for the habitat and therefore also for decision making. Much discussion has recently concentrated on the ‘leaky umbrella’ idea: that by directing too much attention and resources to studying and protecting a single or a few species, we are missing out on the complexities of less well known, less charismatic species which are equally critical in maintaining ecosystems.

The relationship between prey, carnivores and scavengers occurs across the globe in many different habitats but rarely received much research attention. One of the key questions is just how important are carnivores in making carrion available to scavengers? In their paper, published in Journal of Applied Ecology, Perrig and co-authors investigated the relationships between Andean puma (Puma concolor) predation on its native camelid prey, vicuñas (Vicugna vicugna) and guanacos (Lama guanicoe), in food provisioning for Andean condors (Vultur gryphus) in the high Andes of north-western Argentina. This area provides a particularly good site to investigate this relationship as there is no hunting and there are few domestic animals in the area, a common source of food for scavengers in other areas.

Andean puma, vicuña and Andean condor.

Although indicators based on individual species can be useful for developing support for a monitoring program or evoking a public response to an environmental issue, the reliability of individual species as indicators can be problematic if there is little consideration of their role in the wider ecosystem e.g. apex predators and availability of food. Perrig et al.’s work provides yet more evidence that conservation of a community or guild of animals is more effective and more likely to lead to positive long-term conservation impacts than focussing on a single species. Their call for more conservation focus on community intactness for long-term and simultaneous conservation of multiple species should be heeded.