Project Title: Predicting Tidal Currents for the Aleutian Islands and Gulf of Alaska
Goal or Purpose

To parameterize a regional tidal current model for Alaska and use it as an input for predictive modeling of deep sponge and coral distribution and abundance.

Anticipated Management Application(s)

Accurate predictions of the locations of coral and sponge communities in the Gulf of Alaska and Aleutian Islands allow managers to better determine the effects of alternative management actions and potential ongoing and new threats to coral and sponge communities.

Fiscal Funding:
  • FY 2012 @ $30,000

 
Region(s):
  • North Pacific Council
Location(s):
  •  None Defined.
Maximum tidal current (cm/s) for the Aleutian Islands to 500 m depth as predicted by a regional tidal inversion model. Credit: C. Rooper, NOAA Fisheries AFSC
Project Type:
  • Habitat Suitability Modeling
Point of Contact: Office of the Point of Contact:
  • NMFS AFSC
Team Members:
  •  None Defined.
Project Title: Predicting Tidal Currents for the Aleutian Islands and Gulf of Alaska
Methods/Approach

In the Aleutian Islands, tidal currents are the most important sources of water movement in terms of volume and velocity, and thus the dominant force for transporting food and propagules to/from deep-sea coral and sponges. Better predictions of these currents are important for knowing where coral and sponge habitat is likely to occur and can be obtained by developing a regional tidal prediction model for the Aleutian Islands. The approach of this project was to develop a regional tidal current model on approximately 1 km grid by incorporating the best bathymetry data available and tuning the model to fit field observations of tides. This work was done under contract by Dr. Gary Egbert and Dr. Lana Erofeeva at Oregon State University, where a previous tidal model was developed for other regions in Alaska (i.e. the eastern Bering Sea Shelf). The resulting tidal current model was used as a variable to predict the presence and absence of coral and sponge at locations in the Aleutian Islands as well as predicting the abundance of these benthic organisms.

Project Results and Management Outcomes

To date, the tidal current model results have been used to construct predictive models of the distribution of deep-sea coral and sponge in the Aleutian Islands. The maximum tidal current has been found to be the most important predictor of sponge and coral distributions (aside from geographic position). This modeling has resulted in maps predicting where these organisms occur in the Aleutian Islands and a manuscript in press describing the results. Preliminary predictions of sponge and coral distributions in the Gulf of Alaska have also been made using the tidal model output.

Project Title: Predicting Tidal Currents for the Aleutian Islands and Gulf of Alaska
Internal References:
  •  None Defined
 
Backlinks:
  •  None Defined

FY12_03_image.jpg
Maximum tidal current (cm/s) for the Aleutian Islands to 500 m depth as predicted by a regional tidal inversion model. Credit: C. Rooper, NOAA Fisheries AFSC