Mammal species biodiversity in a Costa Rican protected tropical rainforest environment

Abstract

Tropical rainforest deforestation has led to old-growth forest loss and declines in species diversity worldwide. In the 1980’s, Costa Rica began innovative reforestation efforts and currently 52% of Costa Rica is a tropical forest environment. However, the impact of Costa Rica’s reforestation efforts on regaining species biodiversity is less known. The aim of this study was to consider longitudinal changes in mammal biodiversity at La Selva Biological Station (LSBS) following reforestation. Mammal species census data were collected between 1994 and 2017 by 30-60 trained and experienced Citizen Scientists. We calculated the total number of different species sighted per year, their relative abundance, and the Shannon Index to estimate biodiversity. Linear regression was used to consider change over time and ANOVA was used to consider differences in land and water use by mammal species (p<0.05). Results suggest the total number of different species observed declined, their relative abundance declined, and the Shannon index of biodiversity declined (p<0.05). This decline is similar to that reported for avian fauna, terrestrial amphibian, and dung beetle species reported at LSBS. Our study highlights the concern that past deforestation continues to lead to species decline and the ongoing need for tropical forest stewardship.