DOI: 10.5061/dryad.2z34tmptw
title: Scavenging and social interaction of an apex avian scavenger is governed by bioregional and seasonal variation

description: Apex scavengers can perform an important ecosystem service by rapidly
 removing carrion, in turn regulating nutrient cycling linked to carcass
 decomposition. Yet, our understanding of the biotic and abiotic factors
 that influence rates of apex scavenging and their behaviour around carrion
 remains limited, in part because of the absence of replicated studies
 across different bioregions, habitats and seasons. Here, we examine the
 use of carrion by one of Australia’s apex scavengers, the wedge-tailed
 eagle (Aquila audax), and uncover the extent and consequences of their
 social interactions at carrion. We applied a standardised design to
 monitor 120 kangaroo (Family: Macropodidae) carcasses using camera traps
 across contrasting bioregions (Desert, Forest and Alpine), habitats (open
 and closed canopy) and seasons (warm and cool). We predicted that
 wedge-tailed eagles would discover carcasses quicker in open habitats, and
 that intrinsic carrion value (ICV), or the desirability of carrion, would
 be related to dietary stress as a function of productivity and season
 (i.e. we expected to see increased carcass use by eagles in the less
 productive Desert bioregion and in cooler seasons). Across all bioregions,
 we found that wedge-tailed eagles discovered carcasses in open habitats
 2.7 times faster than in closed habitats and 5.3 times faster in cool
 seasons compared with warm seasons. Scavenging was less likely to occur in
 open environments, was more frequent in cool seasons and in the Desert
 bioregion. ICV largely governed social interactions; there were more
 aggressive encounters between wedge-tailed eagles during cool seasons and
 in the Desert bioregion. Our results highlight how bioregional, habitat,
 and seasonal variation can drive scavenging rates and social interactions
 between conspecific apex scavengers. Further studies considering both
 carrion use and corresponding behavioural interactions will enhance our
 understanding of how carrion contributes to shaping interactions between
 and within species groups as well as scavenger communities more broadly.
description: # Wedge-tailed eagle scavenging and social behaviour
 [https://doi.org/10.5061/dryad.2z34tmptw](https://doi.org/10.5061/dryad.2z34tmptw) Contains the summarised data from camera traps used to analyse the scavenging and social behaviours of wedge-tailed eagles In all sheets, station refers to carcass site, region refers to one of the three study bioregions (Alpine, Desert, or Forest), and habitat refers to the habitat in which the carcass was placed (Open or Closed).  Refer to "Scavenging and social interaction of an apex avian scavenger is governed by bioregional and seasonal variation" - 10.1111/oik.10826 for specific protocols on how behaviours were characterised and collected as well as the classifications of scavenging events. The sheets contained within the excel are explained below: "zeroinflated behav" * Aggressive_conspecific - number of aggressive interactions between eagles  * Aggressive_interspecific - number of aggressive interactions from eagles and interspecifics * Negative - number of aggressive interactions from interspecifics to eagles * Neutral_conspecific - number of neutral interactions between eagles where two individuals were recorded interacting with the carcass simultaneously * Neutral_interspecific - number of neutral interactions between eagles and interspecifics where an eagle and interspecific species were recorded interacting with the carcass simultaneously * aggressivesum - aggressive_conspecific + aggressive_interspecific "zero inflated scav freq" * Frequency refers to the number of scavenging events at each carcass "Scavenging frequency data" - is scavenging frequency at each site with the exclusion of any sites with no scavenging "Carcass Discovery data" * Mintime - refers to the datetime of the first scavenging event  * deploydatetime - refers to the date of carcass deployment * discoverytime - time it took for a wedge-tailed eagle to discover the carcass  * Event - binary indicator of whether carcass was discovered (0 - undiscovered, 1 - discovered)  "Aggression since deployment" for analysis into aggression since carcass deployment, includes both conspecific and interspecific aggression * Round - refers to number of days since carcass deployment rounded to the nearest decimal day * D.interaction - classification of aggressive interaction, either conspecific or interspecific  * Count - number of interactions