DOI: 10.5061/dryad.1zcrjdfnm
title: Data from: Fear of the dark? contrasting impacts of humans vs lynx on diel activity of roe deer across Europe

description: Humans, as super predators, can have strong effects on wildlife behaviour,
 including profound modifications of diel activity patterns. Subsequent to
 the return of large carnivores to human-modified ecosystems, many prey
 species have adjusted their spatial behaviour to the contrasting
 landscapes of fear generated by both their natural predators and
 anthropogenic pressures. The effects of predation risk on temporal shifts
 in diel activity of prey, however, remain largely unexplored in
 human-dominated landscapes. We investigated the influence of the density
 of lynx (Lynx lynx), a nocturnal predator, on the diel activity patterns
 of their main prey, the roe deer (Capreolus capreolus), across a gradient
 of human disturbance and hunting at the European scale. Based on 11
 million activity records from 431 individually GPS-monitored roe deer in
 12 populations within the EURODEER network (http://eurodeer.org), we
 investigated how lynx predation risk in combination with both lethal and
 non-lethal human activities affected deer diurnality.  We
 demonstrated marked plasticity in roe deer diel activity patterns in
 response to spatio-temporal variations in risk, mostly due to human
 activities. In particular, roe deer decreased their level of diurnality by
 a factor of 1.37 when the background level of general human disturbance
 was high. Hunting exacerbated this effect, as during the hunting season
 deer switched most of their activity to nighttime and, to a lesser extent,
 to dawn, although this pattern varied noticeably in relation to lynx
 density. Indeed, in the presence of lynx, their main natural predator, roe
 deer were relatively more diurnal. Overall, our results revealed a strong
 influence of human activities and the presence of lynx on diel shifts in
 roe deer activity. In the context of the recovery of large carnivores
 across Europe, we provide important insights about the effects of
 predators on the behavioural responses of their prey in human-dominated
 ecosystems. Modifications in the temporal partitioning of ungulate
 activity as a response to human activities may facilitate human-wildlife
 coexistence, but likely also have knock-on effects for predator-prey
 interactions, with cascading effects on ecosystem functioning.
description: <b>deer_id</b><br> Roe deer identity –
 individual-specific unique identifier for each monitored roe
 deer <b>year</b><br> Monitoring
 year [2003-2015] <b>julian_date
 </b><br> Number of days since January
 1<sup>st</sup> of a given year
 <b>area_subarea</b><br> Study area
 identity <b>subarea_name</b><br> Name
 of the subarea – when several subareas in a given study site
 <b>study_name</b><br> Name of the study
 site <b>hfi</b><br> Human Footprint
 Index – mean index of the overall level of human activities (based on
 Venter et al. 2016) within each individual’s seasonal home-ranges [4 -
 34] <b>predator_presence</b><br>
 Predation risk - indexed by the presence of lynx and its relative density
 for each study site no_lynx = absence of
 lynx lynx_low =
 low density of lynx (sites with transient lynx and densities of ~ 1
 lynx/100km²) lynx_high = high density of lynx
 (sites with densities of ~ 2 lynx/100km²)
 <b>sex</b><br> m = males f =
 females <b>diurnality_index</b><br>
 Index of diurnality (continuous) – relative level of activity during
 daylight compared to nighttime for each individual on each given day (see
 more details on the calculation in the manuscript)
 <b>crepuscularity_index</b><br> Index of
 crepuscularity – relative level of activity during daylight compared to
 nighttime for each individual on each given day (see more details on the
 calculation in the manuscript)
 <b>day_period</b><br> Period of the day related
 to the crepuscularity index (sunset or sunrise)