Between January to August 2007, the pluvial ecosystem in a deforestation gradient on the neotropical stream (Río Capira), Panama was assessed. Six sampling sites were used to measure biodiversity and water quality to know the impact of alteration habitat on stream. External sites to Altos de Campana National Park (PNAC) show similar taxonomical composition, nevertheless in the sites within PNAC rare taxa are found, causing dissimilitude the remaining sites sampled outside the National Park. Physicochemicals variables showed fluctuations along sites studies and season. The water quality index BMWP/CR, BMWP/Col and ICA/Pan showed that water quality change between sites and season. The sites downstream resulted in major habitat alteration to human settlement and the precipitations resulted as most important factor to explain variation in water chemistry that affect benthic macroinvertebrate assemblages. This study brings valuable information about habitat alteration effects in the structure of benthic macroinvertebrates inside and outside of the protected area.
