17 Species Distribution Indicators
Description: Species mean depth, along-shelf distance, and distance to coastline
Found in: State of the Ecosystem - Gulf of Maine & Georges Bank (2017+), State of the Ecosystem - Mid-Atlantic (2017+)
Indicator category: Extensive analysis; not yet published
Contributor(s): Kevin Friedland
Data steward: Kevin Friedland, kevin.friedland@noaa.gov
Point of contact: Kevin Friedland, kevin.friedland@noaa.gov
Public availability statement: Source data are available upon request (read more here). Derived data may be downloaded here.
17.1 Methods
Three metrics quantifying spatial-temporal distribution shifts within fish populations were developed by Kevin D. Friedland et al. (2018), including mean depth, along-shelf distance, and distance to coastline. Along-shelf distance is a metric for quantifying the distribution of a species through time along the axis of the US Northeast Continental Shelf, which extends northeastward from the Outer Banks of North Carolina. Values in the derived time series correspond to mean distance in km from the southwest origin of the along-shelf axis at 0 km. The along-shelf axis begins at 76.53°W 34.60°N and terminates at 65.71°W 43.49°N.
Once mean distance is found, depth of occurrence and distance to coastline can be calculated for each species’ positional center. Analyses present in the State of the Ecosystem (SOE) reports include mean depth and along-shelf distance for Atlantic cod, sea scallop, summer flounder, and black sea bass.
17.1.1 Data sources
Data for these indicators were derived from fishery-independent bottom trawl survey data collected by the Northeast Fisheries Science Center (NEFSC).
17.1.2 Data analysis
Species distribution indicators were derived using the R code found here.
17.1.3 Data processing
Distribution indicators were further formatted for inclusion in the ecodata R package using the R code found here.
catalog link https://noaa-edab.github.io/catalog/species_dist.html