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Data for: Living in fear: How experience shapes caribou responses to predation risk

Cite this dataset

Derguy, Laurie; Leblond, Mathieu; St-Laurent, Martin-Hugues (2024). Data for: Living in fear: How experience shapes caribou responses to predation risk [Dataset]. Dryad. https://doi.org/10.5061/dryad.02v6wwq5c

Abstract

Wild prey can reduce predation risk by avoiding areas used by their predators. As they get older, individuals should be able to fine-tune this avoidance based on their increased experience with predators and cues associated with predation risk. Such learning mechanisms are expected to play a key role in how individuals may cope with risk during their life, particularly in altered landscapes where human disturbances have created habitat conditions distinct from those of the past. We studied the role of experience on the avoidance of risky areas by boreal caribou (Rangifer tarandus caribou) in a system where they are under high predation pressure from grey wolves (Canis lupus) and black bears (Ursus americanus). We described the behavioural responses of caribou to variations in the risk of encountering wolves and bears, investigating whether individuals adjusted their level of predator avoidance with passing monitoring years, a proxy of increasing experience. We used telemetry data collected on 31 wolves and 12 bears to map spatial variations in the risk of encountering predators. We used data from 28 collared female caribou monitored for 3–8 years (mean ± SD: 4.4 ± 2.2) to assess trends in the avoidance of risky areas by caribou with passing years. We observed an increase in the avoidance of areas suitable to wolves with passing years, except during winter and calving when females did not adjust their avoidance of wolves. We also found an increase in the avoidance of areas suitable to bears across all study periods. These results suggest that, in most circumstances, caribou became more efficient at avoiding areas selected by their main predators as they gained experience throughout their life. Provided the avoidance tactics observed in this study are heritable and offer fitness advantages to the individuals that display them, our results suggest that caribou populations living in disturbed environments may have the potential to adapt to changing predation risk. Our findings have encouraging implications for caribou and wildlife conservation in general, as they suggest that experience may allow prey to adjust to novel conditions, including higher predation risk.

README

Databases for final caribou RSFs

*** this README file is the same for the four datasets that are representing different risk periods***

Description of column names:

  • IDENT: caribou individual number

  • RISK_PERIOD: biological period of risk of this dataset

  • presence: GPS location (1) or random point (0); this is the dependent variable of the RSF

  • habitat: the original habitat categories for caribou that are presented as dummy variables (0 or 1) in columns E to N and that are detailed in Table 1.

  • Cut_0_5: ≤5-year-old natural disturbances and cutblocks

  • Cut_6_20: 6–20-year-old cutblocks

  • Decid_Mixt_Mature: ≥50-year-old mixed and deciduous stands

  • NatPert_6_20: 6–20-year-old natural disturbances (mostly fires)

  • OpenLichenWoodlands: Open woodlands often rich in lichens and bare areas

  • Other: Human infrastructures, water bodies, non-regenerated areas and rare habitat features

  • OldMatForest: >90-year-old conifer stands

  • Regeneration: 21–50-year-old regenerating stands originating from natural or anthropogenic disturbances

  • Wetlands: Bogs, fens, flooded areas, and alder stands

  • YgMatForest: 50–90-year-old conifer stands

  • IDYEARPERIOD: caribou individual number combined with the year and the period of risk

  • ELEV_ORI: elevation in meter

  • SLOPE_ORI: slope in degrees

  • MAJOR_EUCL_ORI: Euclidian distance to the closest major (paved) road in meter

  • MINOR_EUCL_ORI: Euclidian distance to the closest minor (gravel) road in meter

  • IDENT_YEAR: caribou individual number combined with year

  • ROADS_EUCL_ORI: Euclidian distance to the closest road (all confounded) in meter

  • DECAY25: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 25

  • DECAY50: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 50

  • DECAY75: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 75

  • DECAY100: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 100

  • DECAY150: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 150

  • DECAY200: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 200

  • DECAY300: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 300

  • DECAY500: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 500

  • DECAY750: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 750

  • DECAY1000: Decay distance to the closest road (all confounded) transformed following Carpenter et al. (2010) equation, with an alpha value of 1000

  • MAJ_DECAY25: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 25

  • MAJ_DECAY50: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 50

  • MAJ_DECAY75: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 75

  • MAJ_DECAY100: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 100

  • MAJ_DECAY150: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 150

  • MAJ_DECAY200: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 200

  • MAJ_DECAY300: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 300

  • MAJ_DECAY500: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 500

  • MAJ_DECAY750: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 750

  • MAJ_DECAY1000: Decay distance to the closest major road transformed following Carpenter et al. (2010) equation, with an alpha value of 1000

  • MIN_DECAY25: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 25

  • MIN_DECAY50: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 50

  • MIN_DECAY75: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 75

  • MIN_DECAY100: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 100

  • MIN_DECAY150: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 150

  • MIN_DECAY200: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 200

  • MIN_DECAY300: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 300

  • MIN_DECAY500: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 500

  • MIN_DECAY750: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 750

  • MIN_DECAY1000: Decay distance to the closest minor road transformed following Carpenter et al. (2010) equation, with an alpha value of 1000

  • ELEV2_ORI: the square value of elevation (column P)

  • habwolf: the habitat categories for wolf RSF that are presented as dummy variables (0 or 1) in columns BB to BI and detailed in Table 1.

  • L_Decid_Mixt_Mature: ≥50-year-old mixed and deciduous stands

  • L_Other: Human infrastructures, water bodies, non-regenerated areas and rare habitat features

  • L_OldMatForest: >90-year-old conifer stands, open woodlands often rich in lichens and bare areas

  • L_Regeneration: 21–50-year-old regenerating stands originating from natural or anthropogenic disturbances

  • L_Wetlands: Bogs, fens, flooded areas, and alder stands

  • L_YgMatForest: 50–90-year-old conifer stands

  • L_Perturb_0_5: ≤5-year-old natural disturbances and cutblocks

  • L_Perturb_6_20: 6–20-year-old natural disturbances and cutblocks

  • habbear: the habitat categories for bear RSF that are presented as dummy variables (0 or 1) in columns BK to BO and detailed in Table 1.

  • O_Mat_Forest: ≥50-year-old mixed or deciduous stands, and 50–90-year-old conifer stands

  • O_Other: Human infrastructures, water bodies, non-regenerated areas and rare habitat features

  • O_OldMatForest: >90-year-old conifer stands and wetlands

  • O_Regeneration: 21–50-year-old regenerating stands originating from natural or anthropogenic disturbances

  • L_Wetlands: Bogs, fens, flooded areas, and alder stands

  • O_Perturb_0_20: ≤20-year-old natural disturbances and cutblocks

  • SEX: Sex of the individual caribou

  • SLOPE: slope value (culumn Q divided by 10)

  • ELEV: elevation transformed in kilometer

  • ELEV2: the square value of elevation in kilometer (column BR)

  • ROADS_EUCL: Euclidian distance to the closest road (all confounded)

  • MINOR_EUCL: Euclidian distance to the closest minor (gravel) road in meter

  • MAJOR_EUCL: Euclidian distance to the closest major (paved) road in meter

  • YEAR_no: the rank of the year of consecutive telemetry monitoring

  • YEAR_rsf: the rank of the year of consecutive telemetry monitoring scaled for a start in 2004

  • RISK_LOUPS: relative probability of occurrence of wolves for this GPS caribou location or caribou random point

  • RISK_OURS: relative probability of occurrence of bears for this GPS caribou location or caribou random point

Methods

From 2004 to 2011 and from 2017 to 2018, 86 adult caribou were captured and fitted with a GPS collar. In the same study area, we collared and monitored 31 grey wolves from 2005 to 2009 and 12 black bears from 2005 to 2006. We defined four annual periods of risk for caribou (winter, spring, calving, and summer), and built resource selection function models of wolves and bears to describe the probability of occurrence of predators. Thereafter, we built resource selection functions using caribou data and tested interactions between the predator probability of occurrence and the passing years (a proxy of experience) to figure out if - and how - caribou adjusted their selection to predation risk with increasing experience.

Funding

Environment and Climate Change Canada

Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs

Ministère des Transports

Université du Québec à Rimouski

World Wildlife Fund Canada

Natural Sciences and Engineering Research Council, Award: 2016-05196

Natural Sciences and Engineering Research Council, Award: 2022-04307