BE/CNH: Agent-Based Modeling of Bering Sea Biocomplexity: Long-Term Ecological Effects of Human Interactions

Idaho State University, Pocatello ID

Investigators

Abstract

The southern Bering Sea and central North Pacific region is considered to be one of the world's most important fisheries. Yet recent catastrophic declines in many species including salmon, Steller sea lion, sea otter, and some pelagic birds show that this ecosystem is neither healthy nor sustainable given modern harvesting rates. Explanations for declines in many species, particularly in relation to several species of salmon, have been monocausal and political without detailed investigations of the relationships between predators (humans and sea mammals) and their prey in this region. Using biological and ecological data, paleoclimatic reconstructions, archaeological data on subsistence and harvesting rates, historic and modern catch and escapement records, ethnographic reports and traditional ecological knowledge, this project will use Swarm agent-based modeling routines to investigate the dynamics of human-salmon-ecosystem interactions in the southern Bering Sea region of Alaska. The multidisciplinary investigative team will develop methods to directly test a number of relationships associated with direct and indirect impacts of changes in one or more sets of human and/or natural systems on the others. This project will begin with a series of monocausal simulations based on natural predator-prey interactions, cultural harvesting strategies, and long-term changes in the Bering Sea ecosystem. The investigators will follow these simulations with multivariate tests in order to investigate interactions between various possible agents. This multivariate testing of simulations should help identify important interaction effects among different agents, even when individual agents have been shown no substantial influence on salmon fisheries. This project will assess the independent and interdependent roles of both human and non-human agents in the modeling process. Humans have lived in the Bering Sea region for at least 10,000 years, and there has never been a time in recent history where humans did not play an important role in the regional ecosystem. This project also will add to knowledge regarding the interplay of agents across multiple temporal and spatial scales. Data will be included from such diverse scales as seasonal catch records of an individual boat, 4,000-year nutrient cycles from lake cores, and a 6,000-year archaeological record of faunal remains. The project also will use of local and indigenous knowledge and will involve local residents in the evaluation of the models and results. The project also should have significant practical implications as it assesses the structure and dynamics of salmon productivity and success in the complex Bering Sea ecosystem. This project is an award emanating from the FY 2001 special competition in Biocomplexity in the Environment focusing on the Dynamics of Coupled Natural and Human Systems.