There are three species of Neotropical cats whose northernmost distribution reaches the USA-Mexico border region: the jaguar Panthera onca, ocelot Leopardus pardalis and jaguarundi Herpailurus yagouaroundi. To ensure the long-term viability of Neotropical cat populations in this region it is imperative to identify current distribution and status in the northern limits of their range to conserve important populations effectively. The purpose of this study was to construct a blueprint of priority conservation areas for each species in the border region. This was done by (1) compiling reliable sightings for each species from the early 1900s to 2003, (2) conducting field surveys to ascertain species presence, and (3) conducting a geographical information system based habitat mapping workshop in which 29 scientists and conservationists provided information on the distribution and status of each species. Participants were asked to delineate and describe specific areas in the border region where historical and recent sightings of Neotropical cats have occurred, resulting in a compilation of 864 felid sightings of which 283 where reliable and had physical evidence. Twenty-one Cat Conservation Units and seven Cat Conservation Corridors were identified as areas in which to concentrate efforts for protecting felids. Only 8.9% of these Corridors and 1.1% of the Units currently have any protection. An additional 12 Corridors and 12 Units were identified as areas requiring further study.

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Dispersal of animals among populations helps to increase genetic variability and population viability. The endangered ocelot (Leopardus pardalis) in south Texas persists in two small populations separated by 30 km and cutoff from populations in northeastern Mexico. Despite the relatively short distance separating the two south Texas populations, movement between them has been limited, leading researchers to believe landscape connectivity is poor in the region. We developed habitat suitability maps using remote sensing and GPS-collared ocelots and ran connectivity analyses to assess current habitat linkages, important areas for conservation, and areas where connectivity could be improved through habitat restoration. First, we developed a resource selection function using random forest models and GPS data from ten ocelots collared at Laguna Atascosa National Wildlife Refuge combined with spatial layers derived from LiDAR and remotely sensed imagery. We then used these results as the basis for a cost surface layer. Using this layer, we examined habitat connectivity using least-cost and circuit theory methods. We evaluated linkages by cost of movement, identified areas important for maintaining existing connectivity, and ranked areas where restoration would have the greatest benefit to connectivity. We found that core habitats within the two populations were relatively well connected but connectivity between the two populations was poor. By identifying areas currently important for connectivity and areas with the greatest benefit to ocelots if restored, these results will help inform land acquisition and restoration planning to improve ocelot conservation in south Texas.

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Reforestation in the Lower Rio Grande Valley (LRGV) of Texas began in the 1960s and to date over 6,475 ha of land has been reforested. However, there has been minimal assessment to understand differential species success, compositional trends, and the aboveground carbon sequestration potential of these developing forests. We coupled quantitative planting information of >50 native woody tree and shrub species with surveys of 5,223 stems of 4,606 individuals in a chronosequence of restored forests ranging in age from 1 to 33 years to estimate species‐specific mortality rates, biomass accumulation and recruitment, as well as compositional trends in the herbaceous understory. We show that 7–15 years are required for mortality rates of the transplanted cohort to stabilize to background levels observed in other dry forests. A small number of species, mostly N‐fixing trees with a deep rooting habit, persisted on the landscape beyond 15 years. Even so, aboveground biomass (corrected for differences in initial planting density) accumulated at an average rate of 1.41 Mg ha−1 yr−1 compared to 0.35 Mg ha−1 yr−1 for a fallow old‐field. Species biomass growth rates increased with decreasing mortality, as did the abundance of recruits, suggesting a degree of reproduction by initial planted cohorts. However, a suite of highly competitive exotic grasses increases in density over a 25‐year period, which we link to suppressed seedling recruitment. This poses a serious challenge to the long‐term sustainability of planted forests in the LRGV. We highlight potential avenues of research and modification to restoration methodologies.