Integrating physiological biomarkers to understand the future of sharks in an oceanic refuge with increasing tourism pressure

• Grant number: 23/10020-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: January 01, 2024
• End date: December 31, 2025
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Fernando Ribeiro Gomes
• Grantee: Bianca de Sousa Rangel
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Persistent anthropogenic disturbances such as those resulting from urbanization, habitat degradation and ecotourism are of substantial concern, once chronically stressful conditions can be pathological and negatively affect individual fitness. Long-lived vertebrates that occupy high trophic levels in the food chain, such as sharks, are ideal models for integrated studies of physiological responses and ecological aspects, since they are often more sensitive to anthropogenic disturbances. Although physiology is intrinsically related to how animals interact with their environment, the use of physiological information to manage interactions between humans and sharks has been limited in this context. Given this scenario, this project proposes to integrate multiple approaches to investigate how environmental disturbances driven by increasing tourism and urbanization in the Fernando de Noronha Archipelago affect patterns of habitat use, energetic metabolism, immunocompetence and osmoregulation of young sharks from two species with different life histories, the lemon shark (Negaprion brevirostris) and the Caribbean reef shark (Carcharhinus perezi). It will be tested the hypothesis that sharks more exposed to human activities within the sustainable use area in the high tourism season period would have important physiological changes indicative of chronic stress, including compromised in nutritional status, and reduction in immunocompetence and growth rate, when compared to sharks within the Marine National Park area in the low tourism season. This project will therefore help to elucidate the possible impacts of increasing tourist activity in an oceanic nursery area, as well as possible ways of mitigating recreational activities.