A call to further understand the role of carrion in food webs: a case study of the Australian Alps

ABSTRACT Carcasses are integral to the structure and function of ecosystems, providing a food source for a variety of scavenger species that recycle nutrients back into the biosphere. However, in many systems globally there is limited information on the extent of carcass use by scavengers and the length of carcass persistence. This prevents land managers from making well-informed decisions on whether carcasses should be removed if produced in excessive numbers following activities such as culling, or extreme weather and disease outbreaks, or when to undertake management operations that add to the overall carcass biomass in ecosystems. In this paper, we focus on the Australian Alps and highlight results from recent studies to show that carcasses persist in this bioregion for long periods in winter when insects are less active. We show that vertebrate scavenging rates are relatively low in the Australian Alps compared to other bioregions in Australia, and that carcasses in this system can become hotspots for introduced species like European wasps (Vespula germanica), red foxes (Vulpes vulpes), and feral pigs (Sus scrofa). We advocate that further carcass monitoring in the Australian Alps should focus on scavenger use and persistence rates for different carcasses species, including across different elevations, seasons, and following culling operations. This will ultimately help to guide understanding around when native scavenger guilds can effectively accelerate carcass biomass loss, which is a key indicator of a healthy, functioning ecosystem.