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INFLUENCIA DEL HÁBITAT Y LA ESTACIONALIDAD SOBRE LA DIETA DEL OSO ANDINO (Tremarctos ornatus) EN EL DISTRITO DE COROSHA, DEPARTAMENTO DE AMAZONAS

  • February 2018
  • Thesis for: BSc
  • Advisor: Jessica Amanzo
Authors:
Alexandra Mireya Chávez Argandoña at University of Münster
Alexandra Mireya Chávez Argandoña
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Decrease in endemic fauna and flora populations has motivated taking conservation actions to preserve the species, actions such as delimiting critic areas which can be formulated knowing the ecology of the species, particularly their feeding habits. One of these threatened species is the Andean bear (Tremarctos ornatus). Its diet analysis has shown an opportunistic omnivorous diet with differences between seasons, but between habitats. Its diet is based on the Bromeliaceae family, showing a preference towards fruits intake. Two of the ecosystems that T. ornatus inhabits in Peru are the montane cloud forest and the jalca of the Amazonas department, where knowledge on its diet and the effect of the habitat and the seasonality over it is limited. Thus, the present research aims to determine if the feeding habits of T. ornatus keep mainly herbivorous and if there is a difference on the species intake between the jalca and montane cloud forest habitats, and between the rain and dry seasons. The analysis of scats and feeding sites of T. ornatus, done through the microhistological analysis of plants, showed a mainly herviborous generalist diet, where the families Bromeliaceae, Ericaceae and Lauraceae dominated the species eaten. However, during the fructification term of Persea sp. (Lauraceae) T. ornatus showed a specialized diet. The analysis on diet variation regarding the habitats, showed a significant difference between the montane cloud forest and the jalca which was related to the availability of food on each habitat. On the other hand, the seasonality effect over the diet showed a differential diet between the rainy season, the beginning of the dry season and the end of the dry season. These variations could have been produced by the fructification term of some Ericaceae species and of the species Persea sp., which would have a role as a key species in T. ornatus diet.
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