Freshwater Aquatic - Richness of Fish of Conservation Concern

Richness of Fish of Conservation Concern

This layer is one of the South Atlantic LCC indicators in the freshwater aquatic ecosystem. To read more about the indicators and how they are being used, please visit the indicator page.

Reason for selection

Fish of conservation concern provide an indicator of cumulative impacts to the freshwater aquatic ecosystem and are regularly monitored throughout the LCC

Input Data

• Draft fish database from the Southeast Aquatic Connectivity Assessment Program (SEACAP) - Includes data from all three sources below

• NatureServe Digital Distribution of Native U.S. Fishes by Watershed

• Biodiversity Information Serving our Nation (BISON) species occurrence data

• Multi-state aquatic resource information system (MARIS)

Mapping Steps

• Extracted occurrences of all fish species with either NatureServe GRanks less than G5 (Stable) or with ranges that were completely contained within the South Atlantic LCC boundaries (Endemic)

• Used SEACAP database (see “Input Data”) for all species covered by that database. Occurrences in that database are already summarized by HUC8

• Used NatureServe and BISON database for any species not in SEACAP database

• Only one species did not have occurrence data in any of the databases: “Carolina Madtom” - Noturus sp. cf. leptacanthus

GIS Processing

All indicators were initially computed, or in the case of existing data, were resampled to 1 ha spatial resolution using the nearest neighbor method. For computational reasons, we then used the Spatial Analyst aggregate function to rescale the resolution to 200 m. The aggregate function avoided loss of detail by taking the maximum value of each cell in the conversion (e.g., species presence).