Lower Columbia River Estuary - PowerPoint by LFnO319

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									Lower Columbia River Estuary


       Mapping Subtidal Large Woody Debris and
       Other Habitat Features Relative to Fish
       Distribution




       Battelle – Pacific Northwest Division
       Lower Columbia River Estuary Partnership (LCREP)
                                                          12/2/201   1
                                                          1
Objectives
 Map shallow subtidal habitat features (i.e., large
  woody debris (LWD))
   • Merge data with GIS habitat classification maps of wetland
    and intertidal zones
 Relate shallow subtidal habitat features to patterns of
  fish density and distribution
   • Apply innovative fish detection methods to assess
    salmonid use of the habitat features


                                           Battelle – Pacific Northwest Division
                                                                          12/2/201   2
                                       Subbasin Need:
                                       Assess the extent and ecological
                                       significance of various estuarine
                                       habitats, including LWD.
 Photo courtesy of L. Weitkamp, NMFS




Limiting Factor Addressed:
Reduced amount of LWD in streams, sloughs, and
bays of the Lower Columbia River Estuary.

                                                     Battelle – Pacific Northwest Division
   Large Woody Debris Provides:
                         Habitat complexity
                         Juvenile salmon refugia
                         Augmentation of epibenthic prey
Photo courtesy of LTER




 Reduced Levels of LWD due to:
  Logging activities
  Suppression of water flow with reduced flooding
  Removal, meant to prevent fouling of nets



                                       Battelle – Pacific Northwest Division
Study Area (Suggested Site Selection)
Shallow subtidal habitat
in Cathlamet Bay
   • Main channel
   • Channel margin
   • Tidal slough

Battelle and other
interested agencies will
coordinate to select
appropriate sites.


                              Battelle – Pacific Northwest Division
                                                             12/2/201   5
Study Design
YEAR 1
 Project Planning/Design
   •   Develop sampling design and refine site selection for pilot scale
       mapping effort
 Construction/Implementation
   • Mobilize and test side-scan equipment
   • Conduct pilot scale side scan sonar mapping in Cathlamet Bay
   • Conduct video camera surveys
   • Analyze side scan sonar images and classify large woody debris
   • Assess sampling methods and modify for Year 2

                                                    Battelle – Pacific Northwest Division
                                                                                   12/2/201   6
Study Design, continued
 Years 2 and 3 will take an adaptive approach, based on previous results.
YEAR 2
 Repeat side scan sonar mapping and add additional sites
 Mobilize Dual-frequency Identification Sonar (DIDSON)
  acoustic camera and underwater video to quantify fish density
  and behavior at sites with LWD
YEAR 3
 Collect 2nd year of DIDSON and underwater video data
 Re-map LWD (?)
 Spatially link patterns of fish habitat use and abundance to
  distributions of LWD in a GIS framework

                                                  Battelle – Pacific Northwest Division
                                                                                 12/2/201   7
                                                              0   100

Side Scan Sonar
                                                                     meters




 Towed underwater system
 Geo-referenced mosaics
 High-resolution benthic habitat
  and substrate features




                                    Battelle – Pacific Northwest Division
                                                                     12/2/201   8
Side Scan Sonar: Large Woody Debris




 Large woody debris pile,    Large logs and other debris
 dock, piling, and boulder

                                       Battelle – Pacific Northwest Division
                                                                      12/2/201   9
Dual-frequency Identification Sonar (DIDSON)
Acoustic Camera




                              Battelle – Pacific Northwest Division
                                                             12/2/201   10
Dual-frequency Identification Sonar (DIDSON)
Acoustic Camera
                          One fish (~30 cm) swimming
                          near large woody debris

                        Two 50-cm fish and the seabed




                                Battelle – Pacific Northwest Division
                                                               12/2/201   11
Expected Results
 Production of a series of GIS maps depicting distribution of
  LWD relative to bottom features and other relevant geo-
  referenced data
   •   Merge data with GIS habitat classification maps of wetland and
       intertidal zones, currently being developed from Compact Airborne
       Spectrographic Imager (CASI) hyperspectral imagery data
 Physical conditions under which LWD is most commonly
  found
 Variation in location and amount of LWD on annual basis
 Assessment of importance of subtidal LWD as habitat for
  juvenile salmonids


                                                  Battelle – Pacific Northwest Division
                                                                                 12/2/201   12

								
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