Andean bear diet near to and far from a road

Abstract

Despite the existence of several regional studies on the diet of the Andean bear (Tremarctos ornatus), there is a lack of information about the effects of human disturbances on this species' foraging ecology. Our main goal was to compare Andean bear diet composition between a disturbed area (DA) close to a paved road versus an undisturbed area (UA) far away from it, within the Parque Nacional y Área Natural de Manejo Integrado Cotapata, Bolivia. We collected 120 feces samples between October and November 2014—60 samples from each area. We identified 13 species from the feces collected at UA, whereas we identified only 7 species from the feces at DA. Mean number of identified food items per fecal sample at UA was 2.90 (SD = 0.86) and significantly greater (t = –4.32, = 118 df, P < 0.001) than DA mean 1.95 (SD = 1.43). Levin's index points to a specialist diet for Andean bears at both areas, but niche breadth at the UA (0.083) was almost twice the value at DA (0.043). Almost half of the items were found at both the UA and the DA (Jaccard's index = 0.538). Simpson's Diversity index ([UA] = 0.310, [DA] = 0.167) shows that Andean bear diet at the UA was also more equitable, as well as less dominated by a single item (Inverse Simpson index N [DA] = 3.229, N [UA] = 5.997). These results suggest that the presence of a road may affect Andean bear foraging ecology.