Sara Minarro Villanueva: An integrated individual-based model as a tool for socio-ecological management of coral reefs in Indonesia

With the current pace of degradation of coastal marine ecosystems, there is a pressing need for effective tools to facilitate decision-making processes for adequate management. Coral reef ecosystems are particularly sensitive to environmental and human pressures because of their exceptional biodiversity and proximity to increasingly populated coastal areas. Ecosystem services provided by coral reefs are being rapidly diminished. In often isolated tropical island states poor infrastructure and low potential for enforcement may undermine compliance of top down approaches such as fishing restrictions. In certain instances, community-based management strategies may be more feasible. Modeling is a promising means for integrating long-term data from various system compartments to examine how the complex dynamics between them shape ecosystem trajectories under different scenarios. We present the basic structure of an individual-based model simulating the ecological trajectories of marine resources in the Spermonde Archipelago in South Sulawesi, Indonesia, under simultaneous stressors. We used a synthesized functional approach to represent the most relevant ecological compartments and feedbacks among them, focusing on the dynamic effects of human activities as a result of varying socio-economic situations. Basic competition dynamics in benthic communities are modeled as a background, incorporating fish and fishing boats as mobile agents that interact and modify each other and their environment. Socio-economic indicators for each island are used to determine the rules by which fishers select their fishing methods, areas and catch. Other common stressors such as nutrient loading and changing water temperatures are represented through different scenario settings. This model is an attempt to help managers explore the effectiveness of different conservation strategies targeted at resource users in managing coastal marine resources.