Data from: Disentangling woodland caribou movements in response to clearcuts and roads across temporal scales

Although prey species typically respond to the most limiting factors at coarse spatiotemporal scales while addressing biological requirements at finer scales, such behaviour may become challenging for species inhabiting human altered landscapes. We investigated how woodland caribou, a threatened species inhabiting North-American boreal forests, modified their fine-scale movements when confronted with forest management features (i.e. clearcuts and roads). We used GPS telemetry data collected between 2004 and 2010 on 49 female caribou in a managed area in Québec, Canada. Movements were studied using a use – availability design contrasting observed steps (i.e. line connecting two consecutive locations) with random steps (i.e. proxy of immediate habitat availability). Although caribou mostly avoided disturbances, individuals nonetheless modulated their fine-scale response to disturbances on a daily and annual basis, potentially compromising between risk avoidance in periods of higher vulnerability (i.e. calving, early and late winter) during the day and foraging activities in periods of higher energy requirements (i.e. spring, summer and rut) during dusk/dawn and at night. The local context in which females moved was shown to influence their decision to cross clearcut edges and roads. Indeed, although females typically avoided crossing clearcut edges and roads at low densities, crossing rates were found to rapidly increase in greater disturbance densities. In some instance, however, females were less likely to cross edges and roads as densities increased. Females may then be trapped and forced to use disturbed habitats, known to be associated with higher predation risk. We believe that further increases in anthropogenic disturbances could exacerbate such behavioural responses and ultimately lead to population level consequences.Beauchesne Jaeger and St-Laurent_PLoS ONE datasetsCharacteristics of observed and random steps of female Woodland caribou inhabiting a highly disturbed landscape in eastern Canada.Beauchesne et al_datasets PLoS ONE.zi

Disentangling woodland caribou movements in response to clearcuts and roads across temporal scales.

Although prey species typically respond to the most limiting factors at coarse spatiotemporal scales while addressing biological requirements at finer scales, such behaviour may become challenging for species inhabiting human altered landscapes. We investigated how woodland caribou, a threatened species inhabiting North-American boreal forests, modified their fine-scale movements when confronted with forest management features (i.e. clearcuts and roads). We used GPS telemetry data collected between 2004 and 2010 on 49 female caribou in a managed area in Québec, Canada. Movements were studied using a use--availability design contrasting observed steps (i.e. line connecting two consecutive locations) with random steps (i.e. proxy of immediate habitat availability). Although caribou mostly avoided disturbances, individuals nonetheless modulated their fine-scale response to disturbances on a daily and annual basis, potentially compromising between risk avoidance in periods of higher vulnerability (i.e. calving, early and late winter) during the day and foraging activities in periods of higher energy requirements (i.e. spring, summer and rut) during dusk/dawn and at night. The local context in which females moved was shown to influence their decision to cross clearcut edges and roads. Indeed, although females typically avoided crossing clearcut edges and roads at low densities, crossing rates were found to rapidly increase in greater disturbance densities. In some instance, however, females were less likely to cross edges and roads as densities increased. Females may then be trapped and forced to use disturbed habitats, known to be associated with higher predation risk. We believe that further increases in anthropogenic disturbances could exacerbate such behavioural responses and ultimately lead to population level consequences

Comment on "Roadless space of the conterminous United States".

Watts et al. (Reports, 6 May 2007, p. 736) introduced a metric of landscape pattern called roadless volume (RV). However, as with most previous metrics, RV does not explicitly address ecological processes. We demonstrate that RV can produce results inconsistent with the notion of landscape connectivity and contend that more ecologically relevant metrics are available

Candidate model ranking based on QIC for each period of the day and the year.

<p>Models were evaluated using conditional logistic regressions. Only models with ΔQIC≤6 are presented. Number of parameter (K), log-likelihood (LL), difference in QIC values (ΔQIC) and weight (ωi) are given. Model performance was assessed with a Spearman rank correlation (rs±sd). Elevation variables were included in all models tested and models without interactions (i.e. densities of clearcuts edges and roads) are identified with a *.</p

Coefficient estimates (ß) and 95% confidence intervals (95% CI) of the independent variables of the most parsimonious models explaining caribou movements for 49 females in Saguenay – Lac-Saint-Jean (Québec, Canada) between 2004 and 2010 at night.

*<p>Confidence intervals can be obtained by adding and subtracting the ±95% CI value to its associated β value.</p><p>Informative variables were identified with the 95% CI (i.e. not overlapping zero) when available (if not, noted as ‘<i>n/a</i>’) and are identified in bold letters.</p

Number of crossing events.

<p>a) 0–5 years old clearcut edge crossings during calving at night, b) 6–20 years old clearcut edge crossings during summer at dusk/dawn, c) regenerating stand edge crossings during calving at dusk/dawn and d) minor road crossings during early winter at dusk/dawn as a function of their respective edge density around the beginning of the step. The figures were obtained by fitting a curve on the mean number of crossings per steps for individual caribou within intervals of 0.5 km/km² ranging from 0 to the maximum observed density values, compared to the random steps used in the SSF. We chose four representative examples of typical significant interactions obtained through our analysis (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077514#pone-0077514-t003" target="_blank">Tables 3</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077514#pone-0077514-t004" target="_blank">4</a>–5).</p

Coefficient estimates (ß) and 95% confidence intervals (95% CI) of the independent variables of the most parsimonious models explaining caribou movements for 49 females in Saguenay – Lac-Saint-Jean (Québec, Canada) between 2004 and 2010 during daytime.

*<p>Confidence intervals can be obtained by adding and subtracting the ±95% CI value to its associated β value.</p><p>Informative variables were identified with the 95% CI (i.e. not overlapping zero) when available (if not, noted as <i>‘n/a’</i>) and are identified in bold letters.</p

Coefficient estimates (ß) and 95% confidence intervals (95% CI) of the independent variables of the most parsimonious models explaining caribou movements for 49 females in Saguenay – Lac-Saint-Jean (Québec, Canada) between 2004 and 2010 during dusk/dawn.

*<p>Confidence intervals can be obtained by adding and subtracting the ±95% CI value to its associated β value.</p><p>Informative variables were identified with the 95% CI (i.e. not overlapping zero) when available (if not, noted as ‘<i>n/a</i>’) and are identified in bold letters.</p

Description of variables considered in the conditional logistic regressions explaining caribou relative movement probabilities in relation to disturbances for 49 female caribou in Saguenay – Lac-Saint-Jean (Québec, Canada) between 2004 and 2010.

<p>Description of variables considered in the conditional logistic regressions explaining caribou relative movement probabilities in relation to disturbances for 49 female caribou in Saguenay – Lac-Saint-Jean (Québec, Canada) between 2004 and 2010.</p