The Economics of Regime Shifts in Marine Ecosystems
Natural systems are often characterized by limited resilience and the possibility of regime shifts as a consequence of exogenous shocks. Examples include populations with a minimum population size below which extinction is inevitable, and ecological systems with complex interactions between the various components of the system such as shallow lakes and semi-arid rangelands. The ecological literature typically considers regime shifts to be undesirable or even 'catastrophic'. This implies that strengthening resilience of natural systems should be a precondition for sustainability. This thesis takes a new look at this issue by investigating the economic causes and consequences of regime shifts in marine ecosystems. In the following three chapters I study (a) the underlying economic causes of fishery collapse when fishing is unregulated, (b) the implications for efficiency when an ecosystem experiences a shift, and (c) how an optimal management by itself can lead into regime shifts and species collapse. This thesis is just a first step in understanding the economic factors behind regime shifts. Today's fisheries in the developing world are often managed poorly and many species are at the brink of collapse. At the same time, many regions are still strongly dependent on fisheries as the main source of food and employment. Hence, the question how to deal with possible and actual shifts is more pressing than ever. This thesis contributes to the discussion by exposing the relationship between the resource dependency of local economies and regime shifts. It specifies ways to asses the aftermath of regime shifts on the local economy, i.e the changes in economic benefits for different stakeholders.