Despite thousands of hectares of reforestation in Costa Rica, the landscape across the country remains fragmented by patches of large-scale commercial plantations and human communities. These patchy areas have a lack of suitable habitat and prey, meaning there is very little gene flow within meta populations of many mammal & predator species. This study aims to establish a baseline for mammal presence and diversity in the Las Tablas protected zone in order to better inform conservation and habitat restoration efforts. In a camera trap study conducted from January 2023 - May 2023, 37 non-baited cameras were placed across a study area of 328 square kilometers. Sites were selected using a stratified study design, with cameras deployed in forest, farm, and fragment habitat. A total of 839 independent videos captured 29 species of mammals and large-bodied ground birds from 10 different taxa. Videos were analyzed using the Sanderson Method (Harris et al. 2010), for relative abundance, naive occupancy, and absence-presence matrices. White-nosed coati (Nasua narica) had both the highest relative abundance and naive occupancy. Pearson’s correlation used to analyze the relationship between species richness at a site against camera effort as well as different landscape covariates (distance to national park border, distance to a riparian corridor, and patch size) showed effort and patch size to be the strongest predictor of a site’s richness. Shannon-weiner alpha diversity indices were calculated for the three different landscape types. Forest land types had the highest diversity indices while fragments had the lowest. This research provides a comprehensive baseline for mammal presence and diversity to better inform habitat restoration and jaguar conservation efforts in the Las Tablas region.

Land use change driven by human population expansion continues to influence

the integrity and configuration of riparian corridors worldwide. Wildlife viability in semi-arid regions depend heavily on the connectivity of riparian corridors, since water is the primary limiting resource. The Madrean Archipelago in northern Mexico and southwestern United States (US) is a biodiversity hotspot that supports imperiled wildlife like jaguar (Panthera onca) and ocelot (Leopardus pardalis). Recent and ongoing infrastructure developments in the historically understudied US-México borderlands region, such as the border wall and expansion of Federal Highway 2, are altering wildlife movement and disconnecting essential habitat.

I used wildlife cameras to assess species occupancy, abundance, and related habitat variables affecting the use of washes as corridors for mammals in semi-arid Los Ojos (LO), a private ranch within a 530 km2 priority conservation area in Sonora, México located south of the border and Federal Highway 2. From October 2018 to April 2019, I deployed 21 wildlife cameras in five different riparian corridors within LO. I used single- season occupancy models and Royal Nichols abundance models to explore the relationship between habitat variables and use of riparian corridors by mammal communities of conservation concern within this region.

Twenty-one mammal species were recorded in the study area, including American black bear (Ursus americanus), white-tailed deer (Odocoileus virginianus) and the first sighting of jaguar (Panthera onca) in this region in 25 years. For the 11 medium- and large-bodied mammals recorded, habitat variables related to perennial river characteristics (distance to river, weekly water, and site width) and remoteness (distance from highway, elevation, and NDVI) were important for occupancy, but the direction of the relationship varied by species. For commonly observed species such as mountain lion (Puma concolor) and white-nosed coati (Nasua narica), topographic variety was highly informative for species abundance. These results highlight the importance of habitat diversity when identifying corridors for future protection to conserve wildlife communities in semi-arid regions. Additionally, this study provides robust evidence in support of mitigation measures (e.g. funnel fencing, over- or under- passes) along Federal Highway 2, and other barriers such as the border wall, to facilitate wildlife connectivity.