• Authors:
  • Quinn M.R. Webber
  • Michel P. Laforge
  • Maegwin Bonar
  • Alec L. Robitaille
  • Christopher Hart
  • Sana Zabihi-Seissan
  • Eric Vander Wal

This repository contains the code accompanying the paper “The ecology of individual differences empirically applied to space-use and movement tactics”. R scripts are organized in R/ and the Earth Engine script is in EE/. Package dependencies include: data.table, ggplot2, irg, rgdal, gridExtra, sp, spatsoc, toast, adehabitatLT, segmented, rgeos, raster, lme4, MCMCglmm, tidyr, sqldf, lmtest, dplyr.

Movement provides a link between individual behavioral ecology and the spatial and temporal variation in an individual’s landscape. Individual variation in movement traits is an important axis of animal personality, particularly in the context of foraging ecology. We tested whether individual caribou (Rangifer tarandus) displayed plasticity in movement and space-use behavior across a gradient of resource aggregation. We quantified first-passage time and range-use ratio as proxies for movement-related foraging behavior and examined how these traits varied at the individual level across a foraging resource gradient. Our results suggest that individuals adjusted first-passage time, but not range-use ratio, to maximize access to high-quality foraging resources. First-passage time was repeatable and intercepts for first-passage time and range-use ratio were negatively correlated. Individuals matched first-passage time, but not range-use ratio, to the expectations of our patch-use model that maximized access to foraging resources, a result that suggests that individuals acclimated their movement patterns to accommodate both intra- and inter-annual variation in foraging resources on the landscape. Collectively, we highlight repeatable movement and space-use tactics, and provide insight into how individual plasticity in movement interacts with landscape processes to affect the distribution of behavioral phenotypes, and potentially fitness and population dynamics.