DOI: 10.5061/dryad.z612jm6qf
title: The wolf is back! Non-consumptive effects of the return of a large carnivore on the use of supplementary feeding sites by roe deer

description: Understanding how prey species trade-off predation risk and resource
 acquisition is particularly important for advancing our knowledge of
 predator-prey relationships. We investigated this by studying the use of
 concentrated anthropogenic resources, namely supplementary feeding sites,
 by roe deer Capreolus capreolus before and after grey wolf Canis lupus
 recolonisation in an area of the eastern Italian Alps. We used camera
 traps to monitor roe deer visits to feeding sites, where ad libitum food
 was provided, before and after wolf recolonisation, in winter and spring,
 to control for seasonal effects. First, we compared the daily cycle of
 visits using circular statistics. We then used generalised linear mixed
 models to model the occurrence, duration of visits, and tendency to
 congregate at feeding sites as a function of wolf presence and season. Roe
 deer became more diurnal after wolf recolonisation, particularly in
 winter, while in spring they tended to concentrate their visits around
 dusk and dawn. Roe deer visits to feeding sites decreased from winter to
 spring, but only after wolf recolonisation, while their duration was
 shorter in spring when wolves were absent than in any other period. Roe
 deer grouping at feeding sites decreased from winter to spring, especially
 after wolf recolonisation. These results show that roe deer have changed
 their resource use behaviour since the return of the wolf, adopting a
 range of behavioural tactics that could mitigate predation risk, while
 maintaining resource acquisition when more profitable. The increase in
 diurnality may reduce the temporal overlap with wolves’ predominantly
 nocturnal activity; access to the resource-rich, but fairly exposed sites
 mainly occurred during the most limiting season, or with solitary visits.
 We call for further research to understand whether other unmeasured
 processes contribute to shaping the observed patterns, such as demographic
 decline and fine-scale behavioural adjustments (e.g. increased vigilance).
description: # The wolf is back! Non-consumptive effects of the return of a large
 carnivore on the use of supplementary feeding sites by roe deer The data
 consist of 2 tables with data and 1 R code that reproduces all analyses
 (Code_All_Analyses.R). Dataset 1 (Capreolus_last.csv) * Id Event: Id of an
 event of camera trapping (integer) * FS: feeding site ID (integer) *
 Period: Boolean (spring/winter) * Year: year of the event, can be either
 yyyy for spring periods or yyyy/yyyy for winter periods across two
 subsequent years * Presence_wolf: presence of wolf in a given period *
 maxInd: maximum number of individual detected in an event * eventStart:
 timestamp of the first picture of a given event * eventEnd: timestamp of
 the last picture of a given event * eventDuration: duration I seconds of
 the event (difference btw event end and event start) * Male: number of
 males in the event * Female: number of females in the event * Unknown:
 number of animals in the event with sex not identified * Per_Wolf:
 combination of season and presence of wolf (used in the models) Dataset 2
 (Occurrence3.csv) * FS: feeding site ID (integer) * Day_Fact: day of the
 year * Visits: number of daily visits at any FS (events) * Year: year of
 the event * Season: 1 (spring) or 0 (winter) * Presence_wolf: presence of
 wolf in a given period * Per_Wolf: combination of season and presence of
 wolf (used in the models)