Map: Courtesy of Bonneville Power Administration Drainage Area: 660,480 km 2 Estuary Area: 412 km 2.
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Transcript of Map: Courtesy of Bonneville Power Administration Drainage Area: 660,480 km 2 Estuary Area: 412 km 2.
Map: Courtesy of Bonneville Power Administration
Drainage Area: 660,480 km2
Estuary Area: 412 km2
Data Source:Thomas, T.W.1983. Changes in Columbia River estuary habitat types over the past century. CREDDP.
Habitat Changes in the Columbia River estuary
Total area loss = 24%
0
10,000
20,000
30,000
40,000
50,000
Deep Water Medium Depth Shallow/Flats Tidal Marsh &Swamp
Uplands- Natural& Filled
Acr
es
1870
1980- 7 % - 25 %
+ 10 % - 65 %
+ 293 %
HISTORIC AND MODERNCOLUMBIA RIVER ESTUARY FOOD WEBS
HISTORIC AND MODERNCOLUMBIA RIVER ESTUARY FOOD WEBS
Pre-1870Pre-1870 Modern (1980)Modern (1980)
DETRITUS DETRITUS PHYTO-PLANKTON
PHYTO-PLANKTON
FLUVIAL INPUTFLUVIAL INPUT
DETRITUS PHYTO-PLANKTON
EMERGENT PLANTS
BENTHIC ALGAE
PHYTO-PLANKTONDETRITUS
ZOO-PLANKTON ZOO-
PLANKTON
EPI-BENTHOS
? ?
? ?
? EPI-BENTHOSBENTHOS
ZOO-PLANKTON
?
BENTHOS
ZOO-PLANKTON
ZOO-PLANKTON
ZOO-PLANKTON
80000
EPI-BENTHOS
EPI-BENTHOSBENTHOS
BENTHIC ALGAE
EMERGENT PLANTS
159185 ?? ? ?
73000 9000 25 146495 10261440
40560 24
?
11324
1545
3605 36205
1893
355
14587
34 26
282 167279
167
26
10525
5300
1993862629
18251943
OCEANIC EXPORTOCEANIC EXPORT
BENTHOS
Effects of Flow Regulation
• Reduced peak freshet flow by >40% • Freshet longer and peak flow earlier• Greatly increased fall-winter minimum flows
1970-1999Monthly Average Flows at The Dalles
Recommendations from Salmon at River’s End
1. Monitor life-history diversity, habitat use, and performance of juvenile salmon
2. Protect and restore emergent and forested wetlands and riparian floodplains
3. Use physical observations and modeling to assess changes in habitat opportunity
4. Assess the effects of altered habitats and food webs on juvenile salmon
Marsh trap (habitat scale)
Beach seine (landscape scale)
Estuarine Monitoring: Salmon Abundance & Life History
Salmon-Habitat RelationshipsEmergent & Forested Wetlands
• Fish abundance and life history
• Prey availability and fish food habits
• Physical attributes
• Vegetative communities
D. Bottom, NMFS & C. Simenstad, UW
Estuarine Monitoring and Modelling: Physical Attributes & Habitat Opportunity
CORIEHistorical, active
Historical, recent extensions
Historical, temporarily discontinued
This project, active
Planned for 2002
Biological monitoring
• water level (pressure)• salinity• temperature• velocity profiles (5 sites)
Habitat Change Assessment completed 1983
Focus area of NMFS project
Columbia River Estuary Habitat Change Analysis
Historic Habitat Opportunities and Food-Web Linkages of Juvenile Salmon in the Columbia
River Estuary and Their Implications for Managing River Flows and Restoring
Estuarine Habitat
Ed Casillas, Daniel Bottom, Curtis Roegner, Kym Jacobson, & Cathy Tortorici
National Marine Fisheries Service
Charles Simenstad University of Washington
Antonio Baptista, David Jay, & Todd Sanders Oregon Graduate Institute
Eric VolkWashington Department of Fish and Wildlife
Reconstruct historic changes in estuarine rearing opportunities and food-web linkages of Columbia River salmon and evaluate their implications for managing river flows and restoring estuarine habitats.
Research Goal
Simulation Modelling:
2. Effects of change on habitat opportunity?
Food-Web Sources:
3. Effects of change on salmonid food
webs?Restoration Scenarios:
4. Implications for restoration?
Historic Reconstruction:
1. Baseline conditions and modifications?
• Establish a consistent historic habitat baseline from the river mouth to Bonneville Dam.
• Develop baseline of aquatic, intertidal, and floodplain habitats from historic T-Sheet and H-Sheet data.
• Reconstruct historic climatic, tidal, and hydrologic effects on overbank flooding and access to floodplain.
Historic Reconstruction
• Use historic baseline to run 3-D simulations of habitat opportunity based on selected criteria:
--depth (0.1-2.0 m)--velocity (< 30 cm/s)--salinity (< 5 ppt)
• Evaluate sensitivity of habitat opportunity to past (1) diking & filling, (2) flow regulation, and (3) channel deepening.
Simulation Modelling
Food-web Sources
Characterize changes in estuarine food webs of salmon and the organic sources supporting them
1. Stable isotopes: --Carbon sources of different salmon life-history types
--Isotopic signatures of dominant estuarine and freshwater prey
--Otoliths to assess changes in prey linkages
2. Parasites:--Parasite assemblages as indicators of diet and
habitat use
3. Scale microchemistry:--Potential for describing historic food-web linkages
Restoration Scenarios
• Review results of monitoring, simulations, and historic analyses
• Identify alternative restoration scenarios (workshop).
• Construct simulation database for each scenario.
• Analyze impact of alternative scenarios for estuarine habitat and salmon