The relative influence of road characteristics and habitat on adjacent lizard populations in arid shrublands

Kaylan A. Hubbard; Anna D. Chalfoun; Kenneth G. Gerow

doi:10.1670/13-182

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The relative influence of road characteristics and habitat on adjacent lizard populations in arid shrublands

Kaylan A. Hubbard·Anna D. Chalfoun·Kenneth G. Gerow

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Abstract

As road networks continue to expand globally, indirect impacts to adjacent wildlife populations remain largely unknown. Simultaneously, reptile populations are declining worldwide and anthropogenic habitat loss and fragmentation are frequently cited causes. We evaluated the relative influence of three different road characteristics (surface treatment, width, and traffic volume) and habitat features on adjacent populations of Northern Sagebrush Lizards ( Sceloporus graciosus graciosus ), Plateau Fence Lizards ( S. tristichus ), and Greater Short-Horned Lizards ( Phrynosoma hernandesi) in mixed arid shrubland habitats in southwest Wyoming. Neither odds of lizard presence nor relative abundance was significantly related to any of the assessed road characteristics, although there was a trend for higher Sceloporus spp. abundance adjacent to paved roads. Sceloporus spp. relative abundance did not vary systematically with distance to the nearest road. Rather, both Sceloporus spp. and Greater Short-Horned Lizards were associated strongly with particular habitat characteristics adjacent to roads. Sceloporus spp. presence and relative abundance increased with rock cover, relative abundance was associated positively with shrub cover, and presence was associated negatively with grass cover. Greater Short-Horned Lizard presence increased with bare ground and decreased marginally with shrub cover. Our results suggest that habitat attributes are stronger correlates of lizard presence and relative abundance than individual characteristics of adjacent roads, at least in our system. Therefore, an effective conservation approach for these species may be to consider the landscape through which new roads and their associated development would occur, and the impact that placement could have on fragment size and key habitat elements.

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Journal of Herpetology Article

Source-reported bounding extent: 41.00477542222947° to 42.273244264402734° latitude; -110.5059814453125° to -109.0338134765625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Kaylan A. Hubbard, Anna D. Chalfoun, Kenneth G. Gerow. 2016. The relative influence of road characteristics and habitat on adjacent lizard populations in arid shrublands. https://doi.org/10.1670/13-182

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