SPATIAL - Space time Dynamics in Marine Fisheries
SPATIAL is a simulation package developed to model the space-time distribution of fishing intensity using alternative approaches. Three models were built with different input data requirements and output possibilities. ALLOC is a shortrun spatial bieconomic model that represents the interdependencies of smallscale and industrial fleets from different ports of origin, harvesting a target species over several fishing grounds. The space-time distribution of fishing effort of smallscale fisheries was represented, in an indicative way, as a function of estimates of the mean distance of fishing grounds from different ports. ALLOC is based on a simple logistic model for biomass, and considers the dynamic catch per unit of efffort in those grounds over the season, and the corresponding dynamic costs and revenues faced by boats from different ports.
Model YAREA introduces geographically contiguous unit areas, and the realism of age structure. It generates a virgin stock by stochastic patch distribution of recruitment, constrained by a userprovided maximum species biomass spatially distributed in the corresponding grid. YAREA models the spatial dynamics of population structure. It generates spatially distributed fishing intensity as a function of a spatially heterogenous catch per unit of effort, resulting from a nonhomogeneous distribution of population structure and age specific catchability coeficients.
Model CHART was designed to represent the short and longrun spatial dynamics of demersal fisheries as a result of interacting biological, economic, and geographic characteristics. It is an age structured model like YAREA, but incorporates distance from different ports of origin and the shortrun bioeconomic elements of ALLOC. The location of fishing sites are specified in geographic coordinates. When data are available, CHART seems to provide the most compprehensive representation of the space-time distribution of fishing intensity.
These fisheries simulation models can be very useful for training fisheries specialists and for conducting simulation experiments of a wide range of fisheries management strategies. The computer programs were developed in userfriendly interactive format to allow the user to input data and observe the results of simulation experiments.
In order to use this program there is a set of software and hardware requirements which are listed as follows:
Price $US 40