Javelinas (Pecari tajacu) are expanding their range northward in the southwestern United States, but little is known of habitat relationships in northern populations. We used occupancy modeling and maximum entropy modeling of data collected from a camera-trapping grid to investigate javelina occupancy and identify habitat correlates associated with presence in the southern San Andres Mountains of south-central New Mexico. Corrected for incomplete detection, occupancy increased from 0.036 (SE = 0.035) in 2007 to 0.327 (SE = 0.082) by 2011. Presence of javelinas was most strongly associated with areas in close proximity to permanent water sources; with overstory or high shrub canopies of riparian, oak–mountain mahogany, or pinyon–juniper; and with low (< 6%) slopes. Areas with P > 0.75 for javelina presence comprised only 6.7% of the San Andres landscape. Circadian patterns of behavior indicated that javelinas were primarily diurnal during colder months and nocturnal during warmer months. Expansion of javelina occupancy may be related to a slight trend in increasing minimum winter temperatures, because severe winters were hypothesized to limit the northern distribution of javelinas. Additionally, javelinas appear dependent upon a tree or shrub overstory, ideally associated with riparian corridors, to mitigate heat stress associated with occupancy of Chihuahuan Desert habitats.