Laura Palamara, John Manderson, Josh Kohut, Matthew Oliver, John Goff, Steven Gray
Developing Ecological Indicators for Fisheries Management using IOOS Defined Habitat Characteristics in the Mid-Atlantic Bight
ObjectivesObjectives
Model fish distributions (multi- and single-species) using environmental data: benthic AND pelagic
See if we can use remotely sensed data as a surrogate for going out to sea
Apply model results to fisheries management
Important environmental indices EFH, MPA Curb by-catch
Statistical models of fish-habitat associations
NEFSC bottom trawls Spring 2003 - Fall 200765 Species
Bathymetry Sediment Grain Size
Ship Surveys:Bottom Habitat Data
• depth• median• standard deviation
• slope • median• standard deviation
• aspect• median• standard deviation
• profile curvature• median• standard deviation
• tangential curvature• median• standard deviation
• sediment grain size
Ship Surveys:CTD
• temperature• surface• bottom
• salinity • surface• bottom
• stratification• mixed-layer depth• Simpson’s potential energy
• entire water column• top 30 meters
Sea Surface Temperature
Ocean Color
Integrated Ocean Observation Systems:Satellite Data
• sea surface temperature• mean• standard deviation
• water-leaving radiance (ocean color)• 412 nm (M & SD)• 443 nm (M & SD)• 488 nm (M & SD)• 531 nm (M & SD)• 551 nm (M & SD)• 667 nm (M & SD)
• Chlorophyll a• mean• standard deviation
• water mass data
Integrated Ocean Observation Systems:HF radar - ocean currents
Current Velocity
Divergence Trend
• detided & filtered along-shore velocity• detided & filtered cross-shore velocity• variance in raw along-shore velocity• variance in raw cross-shore velocity• divergence
• average• trend
• vorticity• average• trend
Current Velocity
Current Velocity
Current Velocity
Current Velocity
Divergence & Vorticity
Seasonal Divergence Trends
Multivariate Analysis (CCA)Final Environmental Variables Used
Benthic
Depth (log-transformed)Profile curvatureSlope (residuals vs. depth)Sediment grain size
IOOS
SST488 nm reflectance551 nm reflectance (residuals vs. 488 nm)Cross-shore velocityVariance in cross-shore velocityDivergence trend
CTD
Mixed-layer depthSimpson’s PE (limited to top 30 m)Bottom tempBottom salinity (residuals vs. depth)
Community Axis 1
TempDepth
551 nm resids
Benthic IOOS
CTD
21.4% 16.8%
24.8%
5.2%
6.1%16.7%
8.9%
41.6% 47.6%
56.5%
27.5% 33.5%
14.1%
30.9%
22.0%
25.6%
Percent of Explained Community VariationPartial CCA
divergence trend488 nm reflectance
Simpson’s potential energy
bottom T SSTbottom salinity residuals SSTmixed-layer depth current velocity
Squid GAM• Used multivariate results as a guide• Explained approximately 85% of the variation in
squid abundance• Variables included:– bottom temperature– SST x depth interaction– sediment grain size– current velocity– divergence trend– water-leaving radiance: 488 nm
Conclusions
• Pelagic habitat is important• IOOS provides useful measures of the pelagic
habitat• IOOS increases explanatory power of
statistical habitat models
