What happens in a community of scavenging mammals by excluding the dominant species?

    When the dominant facultative scavengers of a scavenger mammal community, such as the fox, are excluded, the community's efficiency in scavenging functions is reduced.


    Carrion is a valuable resource exploited not only by obligate scavengers such as vultures, but also by a wide variety of facultative scavengers such as mesocarnivores. This consumption of carrion plays an important role in the maintenance of ecological processes, affecting species composition and ecosystem functions..

    On the other hand, scavengers provide important supporting, regulatory, and cultural ecosystem services. For example, the removal of carrion by scavengers reduces the probability of disease transmission, improves energy redistribution and transfer within an ecosystem, regulates the negative ecological impacts of some species that may use subsidiary food sources (such as , rats), and reduces the need for human handling of carrion resulting from livestock production and hunting activities.

     

    The Fox (Vulpes vulpes) is a facultative scavenger responsible for removing large numbers of carrion from the environment, helping to reduce disease transmission.

    The extirpation of the main predators and the cessation of the persecution of mesocarnivores as a result of their legal protection, the continuous increase in the fragmentation of the landscape and the increase in agricultural area, are some of the factors that have favored the most adaptable, triggering the growth of generalist mesocarnivore populations in many areas. Despite the importance of scavengers for ecosystem services and human health, Very little is known about the interactions between species of scavenging mammals in Mediterranean ecosystems..

    Thus, It is necessary to understand the relationships and functions of scavenging communities, and to understand how changes in these communities can affect the overall efficiency of their scavenging functions., with special emphasis on the roles that keystone species play in human-altered landscapes.

    Scientists from the Research Group in Game Resources and Wildlife Management of the Instituto de Investigación en Recursos Cinegéticos (IREC – CSIC, UCLM, JCCM) have studied the response of the Mediterranean community of facultative scavenging mammals to the exclusion of larger scavenging species (red fox Vulpes vulpes; european badger, Meles meles; and wild boar, Sus scrofa) using an exclusion fence permeable to species of small scavengers (mainly mongoose, Ichneumon herpes; common genet, genetta genetta; and marten, tuesday foina). To do this, rabbit carcasses monitored by camera traps were placed inside and outside the fence.

    The results show that the exclusion of dominant facultative scavengers led to a significant reduction in the amount of carrion consumed and an increase in carrion available to smaller species, and also to decomposers, over a longer period of time. Although scavenging by non-excluded species increased within the exclusion area relative to the control area, was insufficient to make up for carrion not consumed by dominant scavengers. Of the small scavenger species, only the mongoose significantly increased its carrion consumption in the exclusion area and was the main beneficiary of the exclusion of dominant facultative scavengers.

     

    The mongoose (Ichneumon herpes) was shown to be the main beneficiary of the exclusion of dominant facultative scavengers in an ecosystem.

    Therefore, this research paper indicates that altering the community of facultative scavengers in Mediterranean forests (for example, by controlling fox populations) may reduce the efficiency of small carcass removal and benefit other opportunistic species, such as the mongoose, by increasing the carrion available to them. This interaction could have substantial implications for disease transmission, nutrient cycling, and ecosystem function.

    The scientific publication of this research is available at: