Table 1. Optimized univariate resistance models for each region.

Region	Landscape variablea	Optimal resistance surface	Median R2
DEVA
	Slope	Gaussian (rmax = 100, xopt = 50, xsd = 20)	0.151
	Distance to water	Monotonic positive (rmax = 50, rexp = 4)	0.132
	NDVI	Monotonic negative (rmax = 10, rexp = 0.25)	0.130
	Euclidean distance	—	0.129
GRCA
	Water barriers	Ratio (1,000)	0.173
	Slope	Gaussian (rmax = 10, xopt = 50, xsd = 20)	0.062
	Distance to water	Monotonic positive (rmax = 50, rexp = 1)	0.063
	Euclidean distanceb	—	0.050
MOJA
	Major roads	Ratio (100)	0.227
	Slope	Gaussian (rmax = 10, xopt = 40, xsd = 20)	0.200
	NDVI	Monotonic negative (rmax = 100, rexp = 0.25)	0.186
	Euclidean distance	—	0.173

^a Variables not included in the table did not outperform the null model of isolation by distance (i.e., had lower median Akaike weight) and were excluded from further analysis.

^b Cost distance was log-transformed only for the GRCA Euclidean distance model because untransformed cost distances produced higher model R² for all other resistance models.