Linear forest patches and the conservation of small mammals in human-altered landscapes

Abstract

Linear patches of native forest are commonly found in south-eastern Brazil, where they also serve as boundaries between rural properties. These linear patches can be found connecting forest fragments (possibly acting as vegetation corridors) or isolated and are generally surrounded by agricultural areas (mainly cattle pastures and coffee plantations). In this paper, we assessed the influence of connectivity and type of surrounding agricultural areas on small mammal species in a fragmented landscape. We captured and monitored seven species from which all but one (Rhipidomys itoan) were found in all types of habitat studied (forest fragments, linear patches, and agricultural areas). Community structure was highly similar between forest fragments and linear patches, but differed in agricultural areas. Necromys lasiurus and Calomys cerqueirai were more abundant in agricultural areas and rarely captured elsewhere. Akodon montensis was the most common species and preferred forest fragments. Gracilinanus microtarsus was more abundant in linear patches. Cerradomys subflavus, Oligoryzomys nigripes and R. itoan were equally abundant in forest fragments and linear patches. Small mammal community structure was similar in connected and isolated linear patches. Also, linear patches differed from both types of surrounding agricultural areas – cattle pasture and coffee plantation. Based on the results we concluded that even narrow and isolated linear patches may play an important role for wildlife conservation in a severely fragmented landscape. Therefore, we suggest that conservation efforts should focus on increasing the amount of native vegetation and encourage landowners to maintain the linear forest patches.