The Sierra de Tamaulipas is a biogeographically isolated mountain system in Northern Mexico, where habitat fragmentation by land-management practices is a possible threat to wildlife conservation. As a case example, we used GIS analyses to evaluate how human activities influence the landscape structure of jaguar (Panthera onca) habitat in the region. The study: (1) ranked potential habitat based on associations between environmental attributes (topography, streams and vegetation) and the frequency distribution of jaguar sighting records; (2) classified current land cover from a 1990 Landsat-TM image and mapped the landscape structure of high potential habitat; and (3) compared the degree to which mature natural vegetation is fragmented by different types of owners. Jaguar sites showed significant associations with tropical deciduous and oak forests, and low, west or south-east slopes, between 400 and 900 m. About 52% of the high potential habitat was mapped as mature natural vegetation, which was distributed as two large patches (28% of the land area) and many small forest patches (98% at < 80 ha). The number and size-class distribution of high-potential habitat patches varied little amongst four ownership types, but the dispersed distribution of more subsistence and commercial-based owners across the landscape suggests the need for collaborative participation in a conservation plan. From our study the need to scale up from managing individual land parcels is substantiated and areas that promote regional contiguity of jaguar habitat in the Sierra de Tamaulipas are identified.