Tests were carried out using a negative binomial GLM. Deviance and degrees of freedom ratio illustrate goodness of model fit and the Wald statistic was used to test the significance of model terms. P = porous, NP = non-porous, BE = barrier-end. ORPI = Organ Pipe Cactus National Monument, BA = Buenos Aires National Wildlife Refuge, NRD = Nogales Ranger District (Coronado National Forest), CNM = Coronado National Memorial. Hyphens show where the data could not be computed “due to numerical problems” likely due to the low number of stations and sites registering detections.*Denotes significant results at p values equal to or less than 0.05.