DISSERTATION RESEARCH: Apparent competition or anthropogenic over-harvest: hunting in a multi-species context and its impact on species extinctions in Tropical East Asia

Princeton University, Princeton NJ

Investigators

Abstract

Tropical forests contain most of the world's bird and mammal species, many of which are heavily threatened by overhunting. This project seeks to understand how habitat loss and hunting synergistically affect vertebrate communities. Doctoral Dissertation Improvement funds will complement ongoing research by supporting the collection of detailed information on hunter decision-making behavior, including hunter motivations, their prey preferences, and their searching strategies. The motivation for hunting - whether for subsistence livelihood, commercial markets, or recreation - can determine whether or not excessive hunting is likely to occur. Improved understanding of hunting behavior, in combination with spatial distribution patterns of different species, will improve management of hunting throughout the tropics, as well as in other low-governance areas. Such areas are often committed to the conflicting goals of biodiversity preservation and access by low-income rural populations to natural resources. The project will focus on capacity building and knowledge exchange with local partner institutions, ranging from protected area administration to research stations with local Chinese and Laotian graduate students and faculty. It will contribute significantly to training a graduate student by supporting the integration of social science surveys with existing field research to address an increasing problem. A field study focusing on hunters and a suite of tropical bird species, ranging from species that are widely distributed and rarely hunted to those that have been heavily hunted and occur only in isolated fragments, will be conducted in Tropical East Asia. The investigators posit that the failure of current models to manage exploited populations results from the fact that hunting occurs in a multi-prey context. Common, unprotected prey species can subsidize the exploitation of rare species, a phenomenon called opportunistic exploitation. The researchers will adapt multi-species competition and predation models to include anthropogenic hunting, thereby offering novel predictors for vulnerability to over-exploitation. Point count transects will describe the abundance and distribution patterns of avian species within and around protected areas in Southwest China and Northern Laos. Household interviews of villagers living within 5km of protected areas will be conducted to assess hunter behavioral motivations, and hunting techniques and intensity. The field survey data will inform a mathematical model of multi-species hunting to better understand how to conserve tropical diversity.