Abstract

Ecosystem-based fisheries requires management to consider habitat functions, but how this can be accomplished is often not clear. While habitats represent species and life-stage distributions, more important is how knowledge of habitat abundance, distribution and spatial arrangement can be used to identify spatially explicit, key ecological functions necessary for sustaining fisheries production. Multivariate numerical models are tools for identifying potential production centers, but ecological function can only be incorporated if input data are appropriately designed and scaled, and outputs are appropriately evaluated. We address key functions related to connectivity (ecological flows) using a two-part approach. First, habitats are subdivided to reflect differences in represented fauna, but with particular emphasis on differential habitat use across both species and ontogenetic stages within species, thus ensuring that the habitats needed to support all ontogenetic stages will be represented. Resulting habitats should be in near proximity to enhance the probability of connectivity at the local scale. Second, the known limits of connectivity are defined in terms of distance or locations. These limits are then used to assess the suitability of results. For Puerto Rico, habitats were divided into 22 subcategories [reef/colonized hard bottom (8), uncolonized hard bottom (4), unconsolidated substrate (2), seagrass (3), mangroves (3)], with subcategories relating benthic and/or fish community structure to habitat type, geomorphology and cross-shelf position. For example, mangroves were subdivided into lagoonal, shoreline edges and mangrove keys to account for both community differences and nursery functions. Larval connectivity was 40 km; ontogenetic connectivity requires full cross-shelf representation

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