Spatial and temporal plasticity in free-ranging dogs in sub-Antarctic Chile

Abstract

Free-ranging owned dogs are a conservation concern worldwide, but knowledge on their movement ecology is only recently increasing. To examine unsupervised dog movements into wilderness, we attached Global Positioning System devices to 33 village and four rural dogs on a sub-Antarctic island in Chile during the four seasons of a year (n = 86115 locations). This corresponded to a quarter of the local free-ranging dog population based on a photographic mark-recapture survey. The longest maximum distance to the owner´s home was 20.4 km. The median home range size ranged between 15.8 (spring) and 24.4 ha (summer), but with great individual variation (1.6 ha - 148.8 km2). Nine individuals had home ranges > 100 ha in at least one seasonal monitoring; seven individuals performed excursions spending 1–6 nights in pristine nature, and two individuals accompanied tourists on trekking trips lasting 3–6 days. Remarkably, village dogs were quite active at night (40.7% of the locations). Top-ranked habitats in the compositional analysis of habitat use of village dogs were forest and infrastructure. However, coasts were also important at second order and peatbog at third order habitat selection. Our study revealed a high temporal and spatial plasticity of dog movement in sub-Antarctic ecosystems, likely interacting with wildlife. We conclude that future research should address predictors of problematic animals, which have been treated as “outliers” in many studies. In Chile, the control of legislation and education beyond the mere owner should be improved wherever dogs occur near sensitive wilderness areas.