cursion, areal coverage, reflux), may improve the 

 models. With further refinement and a better under- 

 standing of the relationships driving larval utilization 

 patterns, improvements in the inlet utilization assess- 

 ments may be possible. These improvements would 

 aid managers in assessing the potential impacts to 

 estuarine-catadromous larvae from natural and an- 

 thropogenic modifications of ocean inlets. 



The FLELMR spatial decision support system for 

 coastal resources management. The Florida Estuarine 

 Living Marine Resources (FLELMR) system is a spa- 

 tial decision-support system being developed by the 

 Florida Marine Reseach Institute (FMRI) (Rubec et al. 

 1997). FLELMR has been developed as a source of 

 synthesized biological information needed for fisher- 

 ies management and for assessing potential impacts 

 from oil spills and other perturbations. The system 

 contains information pertaining to the life histories, 

 reproduction and habitat requirements of 91 species 

 of marine fish and invertebrates found in Tampa Bay, 

 Sarasota Bay, Indian River Lagoon and Florida Bay. 

 Text and numeric data are being added to an Oracle® 

 data base. The system is being expanded to include 

 more species, so that researchers can assess the 

 biodiversity and biological integrity of coastal ecosys- 

 tems. Habitat suitability index (HSI) models have 

 been developed, and are used with the Arclnfo® 

 geographic information system (GIS) to map the dis- 

 tributions of species by life stage (Rubec et al. 1999). 

 The FLELMR system will assist resource management 

 decisions by enabling spatial queries with GIS capa- 

 bilities. 



Environmental Sensitivity Index (ESI) mapping. En- 

 vironmental Sensitivity Index (ESI) maps are an inte- 

 gral component of coastal oil spill contingency plan- 

 ning and assessment (Battista et al. 1996). The impor- 

 tance of this response tool warrants the development 

 of a more comprehensive, accurate and easily distrib- 

 uted information system. The update of the ESI Atlas 

 for coastal North Carolina provided an opportunity, 

 as a pilot study, to augment current analog ESI maps 

 and table with digital formats. The Arclnfo® GIS was 

 used to integrate biogeographic data from the ELMR 

 program and salinity data from the National Estuarine 

 Inventory (NEI) with existing ESI data sources. Ulti- 

 mately, digitally integrated data will be available for 

 display, query and analysis via a custom ArcView® 

 desktop GIS system. Final products from this effort 

 include hard-copy maps, digital data bases, and digi- 

 tal coverages that characterize the relative abundance 

 and distribution of fish and invertebrate species in 

 North Carolina estuaries (RPI 1996). A similar series 

 of products have been completed for Georgia (RPI 

 1997) and Massachusetts (RPI 1999). 



Habitat Suitability Modeling (HSM). NOAA's Bio- 

 geography Program is currently developing a GIS- 

 based modeling and assessment capability to investi- 

 gate potential changes in the spatial extent and pat- 

 terns of selected fishery habitats as effected by alter- 

 ations in estuarine habitat. The underlying modeling 

 approach was introduced by the U.S. Fish and Wild- 

 life Service's (USFWS) Habitat Evaluations Proce- 

 dures Program, whereby models result in a numerical 

 index of habitat suitability ranging from 0.0 - 1.0. 

 Models are based on the assumption that a positive 

 relationship exists between the index and a habitat's 

 carrying capacity for a given species (Schamberger et 

 al. 1982). Our models exhibit a significant departure 

 from USFWS methods by incorporating a spatial com- 

 ponent to produce a view of the relative suitability of 

 locations in geographic space through time. The 

 intent is to develop a simple spatial model using GIS 

 technology that offers estuarine resource managers a 

 habitat assessment capability that can be applied to a 

 wide range of estuarine species. 



Habitat Suitability Index models are based upon habi- 

 tat suitability as determined by the combination of 

 environmental variables (i.e., salinity (ppt), water tem- 

 perature (°C), dissolved oxygen content (mg/1), sub- 

 strate type, bathymetry (m), and the presence or ab- 

 sence of submerged aquatic vegetation and emergent 

 wetland macrophytes) as they vary in both time and 

 space. The use of GIS technology provides the tools 

 necessary to produce a "seascape" view of the relative 

 suitability of locations in geographic space through 

 time. Two independent methods are currently used to 

 determine suitability across the range of each param- 

 eter modeled: (1) Qualitative - species suitability 

 index values (Sis) are generated through an extensive 

 data and literature search for documented tolerances 

 to, and affinities for, each environmental and biologi- 

 cal gradient; and (2) Quantitative - Stepwise multiple 

 regression prediction models are developed using 

 empirical data from fisheries-independent data. The 

 former approach is designed to investigate the feasi- 

 bility of developing reasonably accurate habitat suit- 

 ability models in locations lacking data to support a 

 more rigorous statistical model, while the latter is 

 designed to address the concept of transferability of 

 models across geographies. 



Completed HSM studies include: 



(1) Sheepscot Bay and Casco Bay, Maine: Multi-species 

 habitat suitability index models, developed in coop- 

 eration with the U.S. Fish and Wildlife Service Gulf of 

 Maine Program (Brown et al. 1997). 



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