PRESENCE OF AN ENDANGERED ENDEMIC PRIMATE IN AN EVER-CHANGING LANDSCAPE IN THE EASTERN PLAINS OF COLOMBIA

Abstract

Plecturocebus ornatus is an endemic vulnerable species due to its population decline and its restricted range within the Eastern Plains of Colombia. This region is affected by deforestation as a result of legal and illegal economic activities. The aim of this work was to analyze the presence and abundance of P. ornatus during a period of urban and livestock production expansion (1986-2019) in Villavicencio, Colombia. This municipality is the most affected by land-use changes associated with regional economic development and represents 3.4 % of P. ornatus distribution’s area. The analysis was performed using satellite images Landsat 4 and 8, with V-Late in ArcGIS 10.5 to describe landscape structure, and P. ornatus occurrence records, obtained through field observations and the Global Biological Information Facility. Densities were calculated for each fragment based on total individuals observed by transect. A generalized lineal model was used to evaluate the effects of patch-scale, landscape-scale and other variables on P. ornatus abundance. By 1986 the rural and peri-urban areas of Villavicencio were already a transformed landscape. During the analyzed period, landscape was predominantly made up of disconnected linear fragments with a secondary humid forest cover. Around 82.1 % of the fragments with P. ornatus records are threatened by urbanization and only 50 % are in protected areas. Densities varied from 0.00 to 7.26 ind/ha (0.00–726.82 ind/km2). Abundance of P. ornatus was highly influenced by landscape-scale variables related with landscape connectivity, as well as fragment area and number of other primate species. Therefore, the implementation of restoration measures that increase landscape connectivity and habitat availability is proposed, as well as more control over environmental land-use planning, to contribute to the conservation of P. ornatus in urban areas.