Bayesian modelling of catch in a Northwest Atlantic Fishery

This paper deals with the issue of modelling daily catches of fishing boats in the Grand Bank fishing grounds. We have data on catches per species for a number of vessels collected by the European Union (EU) in the context of the Northwest Atlantic Fisheries Organization (NAPO). Many variables can be thought to influence the amount caught: a number of ship characteristics - such as the size of the ship, the fishing technique used, the mesh size of the nets, etc. are obvious candidates, but one can also consider the season or the actual location of the catch. In all, our database leads to 26 possible regressors, resulting in a set of 44 million possible linear regression models for the log of catch. Zero observations are treated separately through a probit model. Prediction of future cathes and poster/or inference will be based on Bayesian model averaging, using a Markov chain Monte Carlo approach. Particular attention is paid to prediction of catch for single and aggregated observations.