The buffy-tufted-ear marmoset (Callithrix aurita) is a small primate endemic to the Brazilian Atlantic Forest biome, and one of the 25 most endangered primates in the world, due to fragmentation, loss of habitat, and invasion by allochthonous Callithrix species. Using occurrence data for C. aurita from published data papers, we employed model selection and cumulative AICc weight (w+) to evaluate whether fragment size, distance to fragments with allochthonous species, altitude, connectivity, and surrounding matrices influence the occurrence of C. aurita within its distributional range. Distance to fragments with C. jacchus (w+ = 0.94) and non-vegetated areas (w+ = 0.59) correlated negatively with C. aurita occurrence. Conversely, the percentage of agriculture and pasture mosaic (w+ = 0.61) and the percentage of savanna formation (w+ = 0.59) in the surrounding matrix correlated positively with C. aurita occurrence. The findings indicate that C. aurita is isolated in forest fragments surrounded by potentially inhospitable matrices, along with the proximity of a more generalist and invasive species, thereby increasing the possibility of introgressive hybridization. The findings also highlighted the importance of landscape factors and allochthonous congeneric species for C. aurita conservation, besides indicating urgency for allochthonous species management. Finally, the approach used here can be applied to improve conservation studies of other endangered species, such as C. flaviceps, which is also endemic to the Brazilian Atlantic Forest and faces the same challenges.
Temporal partitioning is an important mechanism for carnivore mammals that live in sympatry in current forest remnants. We evaluated whether temporal partitioning would facilitate coexistence among carnivores in a tropical forest and its adjacent human-related area, as well as if there is a possible correlation between the activity patterns of these carnivores and their potential prey. We used camera traps and circular statistics to explore the degree of temporal overlap between dominant and subordinate predators, as well as between predators and their potential preys. Pumas (Puma concolor) were less active when jaguars (Panthera onca) were more active. Overall, ocelots (Leopardus pardalis) and crab-eating foxes (Cerdocyon thous) presented either a strong or a weak temporal partitioning with jaguars and pumas, respectively, but apparently spatial or dietary segregation might facilitate more their coexistence with these large predators. Tayras (Eira barbara) and coatis (Nasua nasua) were diurnal and, therefore, did not overlap temporally with nocturnal carnivores, except pumas. In the human-related area, ocelots were mostly nocturnal and pumas diurnal, probably due to the temporal activity of their related preys. Our findings suggest that temporal partitioning may allow coexistence between our studied predators in one of the largest Atlantic Forest remnant in Brazil, but preys have an important role, shifting the activity pattern of their predators according to the studied area.