Understanding how mammalian scavengers use information from avian scavengers: cue from above

Abstract

Interspecific social information transfer can play a key role in many aspects of animal ecology from foraging to habitat selection to predator avoidance. Within scavenging communities, avian scavengers often act as producers and mammalian scavengers act as scroungers, but we predict that species-specific cueing will allow for mammalian scavengers to utilize particular avian scavenger species using preferred food sources similar to their own preferences. We use empirical and theoretic approaches to assess interactions between mammalian and avian scavengers in one of the most diverse scavenging guilds in Masai Mara National Reserve, Kenya. Using a spatially explicit model and data from experimental carcasses, we found evidence that mammals benefit from local enhancement provided by vultures and that mammalian-avian following patterns are consistent with the idea that species-specific cueing is occurring. Results suggest that ongoing population declines in avian scavengers may have significant impacts on mammalian scavengers and potentially create trophic cascades.

Effects of vulture exclusion on carrion consumption by facultative scavengers

“…The clustering of nutrients around a carcass due to a lack of vertebrate scavenging may impact surrounding plant communities and by extension the organisms that consume those plants (Carter, Yellowlees, & Tibbett, ). Although most studies have focused on how vulture declines impact other scavengers, (e.g., Kane & Kendall, ; Morales‐Reyes et al., ; Ogada, Torchin et al., ), our results indicate that the ecological impacts of vulture loss could extend to lower trophic levels as well.…”

The mesoscavenger release hypothesis and implications for ecosystem and human well‐being

“…). Not only are vultures more efficient at locating and consuming carrion in the Masai Mara National Reserve in Kenya, they have also been shown to aid mesoscavengers in locating carrion (Kane & Kendall ). As such, the loss of apex scavengers can result in increased available carrion biomass and slower decomposition time likely due to a lower scavenging efficiency by mesoscavengers.…”

“…The first column of plots is for the baseline mesoscavenger search efficiency, e m = 1. The second column of plots is for the case where mesoscavenger search efficiency is doubled when apex obligate scavengers are present, potentially aiding mesoscavengers in finding carcasses – as documented in some vulture systems (Kane & Kendall ).…”

Social Information Links Individual Behavior to Population and Community Dynamics

“…Furthermore, investigation of dependencies among species, where one species acts as a scout that produces information used by individuals of another species (e.g., lappet-faced and African white-backed vultures [70], eagles and Gyps vultures [58] or avian and mammalian scavengers [100]) illustrate how changes in community structure (e.g., local extinctions) can impact the fate of community members. A positive feedback loop, in which decreasing densities reduce the ability of the remaining individuals to find and/or access resources, can explain frequent population collapses in this guild [14,21,100]. Overall, this integration of approaches (observational, experimental, and modeling) provides insight into the role of social information in driving correlated behaviors in scavenger communities, offering tools to mitigate the detrimental effects of environmental change on the populations and communities of these sanitation providers.…”