![]() Moreover, the emergence of rodent occurrence within the carcass area corresponded well with the disappearance of raven during the second year of the study. = 0.231, p-value = 0.0429), but not fox, presumably due to greater predation risk imposed by large droves of raven. We used the presence and abundance of faeces as a proxy for carcass use over the course of 2 years and found that rodents showed the strongest avoidance towards changes in raven abundance (β = −0.469, s.e. ![]() Here, we use a mass die-off of reindeer caused by lightning in Norway to test whether rodents avoided larger scavengers (e.g. Few studies have applied the landscape of fear to carcasses. Carcass sites can increase species interactions and/or ephemeral, localized landscapes of fear for prey within the vicinity. Further research on scavenger behavior during mass mortality events is needed to better understand the role of scavengers in decomposition of carcasses and disease control during these events.Īnimal carcasses provide an ephemeral pulse of nutrients for scavengers that use them. Telemetry data indicated that approximately half of tagged vultures used mass drowning events but only spent a small proportion of their time there, suggesting that competition still plays an important role in scavenger dynamics at mass mortality events and that the rewards of such abundant resources may be offset by the risk of foraging in the river. Avian scavengers also differed in daily activity patterns, with marabou storks more common in the morning and late afternoon and white‐backed and Rüppell’s vultures more common mid‐day. Scavengers demonstrated patterns of temporal resource partitioning, with large‐bodied avian scavengers more common initially, followed by small‐bodied avian scavengers, and then by insectivorous birds and non‐avian scavengers. Density of avian scavengers per carcass was almost two orders of magnitude lower at mass drownings than has been documented previously for single carcasses on land. In addition, we used telemetry data for tagged avian scavengers to assess individual use of mass drownings. We used photographic time series and river‐side surveys of scavengers using carcasses to investigate scavenger use and succession on wildebeest carcasses that resulted from annual mass drownings in the Mara River, Kenya. Little is currently known about how scavengers respond to large die‐offs and understanding scavenger use and succession patterns at mass mortality events has important implications for disease ecology. Current work on scavenger ecology has focused on use of single carcasses, but behaviors are likely to be different at mass mortality events, in which high resource abundance can prolong the spatial and temporal availability of carcasses. Scavengers play an important role in nutrient recycling and disease control, and this role may be particularly critical after mass mortality events, such as those caused by epidemics, culling, or natural disasters. We pair previous literature with our observations to develop a theoretical basis for developing hypotheses and predictions concerning the relationship between carrion food webs and increasing biomass. Our observations also indicate that rare and novel interactions emerge with extreme amounts of carrion. Here we present empirical and previous literature evidence that indicates ecological interactions indeed change in response to increasing carrion biomass by increasing primary and secondary consumer diversity of species participating in carrion recycling. ![]() With increases in vertical diversity of food webs, basal resource depletion generally decreases because primary consumers are preyed upon. As carrion biomass increases, however, the carrion food web expands to include a more diverse community of secondary consumers that prey upon carrion obligates. Recycling efficiency increases with primary consumer diversity through niche differentiation and facilitation or potentially a sampling effect of having more species and functional groups. Traditional food web theory predicts basal resource availability is linked to bottom-up effects, which may support higher primary consumer biomass and food web diversity. Carrion has well-documented effects on ecosystem processes, but how those effects change with increasing biomass, particularly with extreme amounts of carrion occurring during mass mortality events, is relatively unstudied.
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