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USGS · 70279530

Where will the cat cross the road? Comparing camera and GPS-based models for identifying wildlife corridors

Abstract

Designing effective wildlife corridors is a critical conservation challenge in fragmented landscapes. GPS-based step selection functions strongly predict dispersal corridors and connectivity, but GPS collaring can be expensive and invasive. Camera-based occupancy models are widely used for connectivity analyses but may involve trade-offs in data resolution. Despite widespread use of both approaches, few studies have directly compared them using concurrent datasets. We developed a stacked single-species, single-season occupancy model and a Circuitscape connectivity surface for mountain lions (Puma concolor) on Washington’s Olympic Peninsula, USA, and compared them with a connectivity surface from an existing integrated step selection function. Both models predicted mountain lion GPS locations well, with binned Spearman rank correlations of 1 for Circuitscape and 0.96 for the step selection function, though step selection better identified habitat use by dispersers. Connectivity predictions were moderately correlated across the landscape ( r = 0.26), but agreement was strongest in human-dominated areas most critical for corridor planning. We conclude that GPS-based approaches are advantageous when data collection is feasible and the focus is on dispersal or fine-scale movement. However, camera-based approaches may be preferable for multi-species monitoring, large spatial and temporal scales, noninvasive sampling, when resources are limited, or when fine-scale or dispersal-specific inference is not required.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 46.2616553° to 49.0333246° latitude; -124.792776° to -121.86064076066413° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

Read Barbee, L. Mark Elbroch, Kimberly A. Sager-Fradkin, Kristen Phillips, Dylan L. Bergman, Bethany Ackerman, Shannon L. Murphie, Andrew Stratton, Caitlin Kupar, Cassandra Sullivan, Glen Kalisz, Sarah Nelson Sells, Mark Hebblewhite, Hugh S. Robinson. 2026. Where will the cat cross the road? Comparing camera and GPS-based models for identifying wildlife corridors. https://doi.org/10.1016/j.biocon.2026.112029

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