Terrestrial Mammal Occupancy in the Context of Widespread Forest Loss and a Proposed Interoceanic Canal in Nicaragua's Decreasingly Remote South Caribbean Region.

Christopher A Jordan,Gerald R Urquhart,Cody J Schank,Armando J Dans,Robert Guralnick

doi:10.1371/journal.pone.0151372

Abstract

Central America is experiencing rapid forest loss and habitat degradation both inside and outside of protected areas. Despite increasing deforestation, the Caribbean region of Nicaragua plays an important role in the survival or extinction of large mammal populations in Central America given that it still retains core areas of habitat for large mammal species. The proposed interoceanic canal project that would bisect the southern half of this Caribbean region represents a new threat that, combined with an advancing agricultural frontier, could affect populations of large mammal species such as jaguars, white-lipped peccaries, and Baird’s tapirs. We used occupancy models to examine the relative occupancy probabilities for an assemblage of terrestrial mammals in the south Caribbean region of Nicaragua to identify current core areas for our study species and conduct a preliminary evaluation of the potential impacts of the proposed interoceanic canal. We modeled a community level distribution of eight species with varying levels of sensitivity to human encroachment and a range of habitat associations. Our model results reveal three priority areas for terrestrial mammal conservation in our study area. The mapped predictions show that the only remaining area of suitable habitat for large mammals in the path of the proposed interoceanic canal is a relatively thin strip of forest that runs along the Caribbean Coast. In light of these findings, we propose five recommendations that will help ensure the conservation of this area of the proposed canal route as suitable habitat for our study species.

Highlights

During the past fifteen years, Central America has rapidly emerged as one of the most environmentally threatened regions globally, with several countries posting some of the highest rates of forest loss in the world [1]
To begin examining how increased Mestizo encroachment and the proposed interoceanic canal may affect terrestrial mammals and their core areas of habitat in the RACS and Rio San Juan (RSJ), we examined the occupancy rates of a terrestrial mammal assemblage in the area’s remaining forested landscapes, and projected the results onto species-specific occupancy maps
Our modeling results gave us insight on two general topics: a) the state of core areas for our study species in the southern Caribbean region of Nicaragua and b) the potential effects the proposed Nicaragua canal might have on the occupancy of our study species in the Caribbean region

Summary

Introduction

During the past fifteen years, Central America has rapidly emerged as one of the most environmentally threatened regions globally, with several countries posting some of the highest rates of forest loss in the world [1]. Biologists and politicians collaborated in the early 2000s to design and protect a functioning biological corridor connecting the larger protected areas throughout the Central American isthmus Both the corridor as a whole and protected areas across all levels of protected status (i.e. Biosphere Reserves, Nature Reserves, Wildlife Reserves, etc.) have been degraded and/or destroyed by agricultural encroachment and unsustainable land use practices in recent years [2,3,4]. To begin examining how increased Mestizo encroachment and the proposed interoceanic canal may affect terrestrial mammals and their core areas of habitat in the RACS and RSJ, we examined the occupancy rates of a terrestrial mammal assemblage in the area’s remaining forested landscapes, and projected the results onto species-specific occupancy maps. We used results to identify remaining large tracts of highly suitable habitat for large mammals, assess the effects of different threats to the continued occupancy of terrestrial mammals throughout the entire study area, and observed the relative rates of occupancy for our study species in the vicinity of the proposed canal related infrastructure to assess the potential implications of this large development project

Materials and Methods

Results

Model Results