The Estuary vs. the Watershed: Which Matters More for Anadromous Salmonids? Blake Feist (NWFSC) Richard Hicks (NWFSC) Jonathan Hoekstra (NWFSC) Charles Simenstad (UW Fisheries)

Question Which is more “important” to Pacific salmon, estuarine or terrestrial habitat? Both?

Objective Compare the “condition” of various chinook and coho populations as a function of the “condition” of their associated estuarine and terrestrial habitats

Approach Assess population “condition” at a local scale  Annual population growth rates (Lambda) Assess habitat “condition” at a landscape scale  Estuarine: loss or gain of estuarine salt marsh vegetation  Terrestrial: loss or gain of various land cover and land use types

Population Condition

Population Time Series 1978 – 2000 By age structure: adult, jack, sub-adult Chinook Coho Lambda  Mean yearly growth rate of a population  If > 1, reproducing faster than dying  If < 1, dying faster than reproducing

More on Lambda Dennis-Holmes method based on Holmes 2001 and Dennis et al “Markedly robust to severe sampling error” “Allows estimates of rates and risks of population decline with a well established tool (diffusion approximations) by using age- or stage-specific censuses that are corrupted with sampling error”

Estuarine Habitat

Definition & Sources Salt Marsh: percent habitat remaining on grassland areas bordering estuaries to landward extent of salt marsh vegetation  National Wetland Inventory - estuarine vegetation classifications;  Collins and Sheikh Report 2003 for NWFSC;  Topographic & Hydrographic Sheets (t-sheets, h-sheets) Intertidal: percent estuarine habitat remaining from ~EHW to ~ELW for any given delta  Simenstad et al (synthesis of several older sources);  Simenstad unpubl;  Bortleson et al. 1980;  Good 2000 (unpubl. Estuarine Ecosystem Health Summary Report);  Pacific States Marine Fisheries Commission 2003 (synthesis);  Topographic & Hydrographic Sheets (t-sheets, h-sheets)

Why salt marsh & not intertidal? Intertidal describes area of MLLW to MHHW, and accuracy of assessment was poor; In many places true loss of vegetation is masked; Don’t need all those damn h-sheets!

Comparison of Marsh & Intertidal Methods Average % Loss Marsh = 70.8 ± 31.8 (n = 14) Average % Loss Intertidal = 50.5 ± 33.3 (n = 14) Relationship with methods?  r 2 = 0.58

Everett Harbor - Digital Ortho Quads (DOQ)

Everett Harbor Current Conditions - Digital Ortho Quads (DOQ) - National Wetland Inventory shapefiles - System: Estuarine - Subsystem: Intertidal - Class: Emergent, Scrub-shrub, Forested

Everett Harbor Current Conditions - Digital Ortho Quads (DOQ) - New shapefile delineating NWI classes

Everett Harbor Historical Conditions - Digital Ortho Quads (DOQ) - T-sheet georeferenced to DOQs

Everett Harbor Historical Conditions - T-sheet - Best available historical information - In this case, figure from Collins Report 2003 for NWFSC

Everett Harbor Historical Conditions - T-sheet - Best available historical information - New shapefile delineating historical conditions

Everett Harbor Determining Percent Habitat Change Percent Change = current area – historical area / historical area * 100 % = 58.6 ac – ac/385.2 ac * 100 % ~ 85 %

Terrestrial Habitat

Definition Percent change in given habitat category over the catchment draining into a given estuary * Based on Northwest Habitat Institute Wildlife- Habitat Types * By 6-digit Hydrologic Unit Codes (HUC6) that stream flows through

Washington Northwest Habitat Institute Wildlife Types

Northwest Habitat Institute (NWHI) Agriculture, Pasture, & Mixed Environs Alpine Grasslands & Shrublands Bays & Estuaries Ceanothus-Manzanita Shrublands Coastal Dunes and Beaches Coastal Headlands and Islets Eastside (Interior) Grasslands Eastside (Interior) Mixed Conifer Forest Eastside (Interior) Riparian Wetlands Herbaceous Wetlands Lakes, Rivers, Ponds, and Reservoirs Lodgepole Pine Forest and Woodlands Marine Nearshore Montane Coniferous Wetlands Montane Mixed Conifer Forest Ponderosa Pine & Eastside White Oak Forest & Woodlands Southwest Oregon Mixed Conifer-Hardwood Forest Subalpine Parkland Urban and Mixed Environs Shrub-Steppe Westside Grasslands Westside Lowland Conifer-Hardwood Forest Westside Oak & Dry Douglas-Fir Forest & Woodlands Westside Riparian Wetlands

Historic and Current – Snohomish HUC6 for Chinook Populations  Montane Mixed Conifer Forest  Agriculture, Pasture, & Mixed Environs  Lakes, Rivers, Ponds, & Reservoirs  Westside Lowlands Conifer-Hardwood Forest  Urban & Mixed Environs  Alpine Grasslands & Shrublands  Westside Oak & Dry Douglas-Fir Forest & Woodlands  Herbaceous Wetlands  Bays & Estuaries  Westside Riparian- Wetlands  Subalpine Parkland “Pre-Settlement” “Current”

Historic and Current – Everett Harbor Snohomish, Snoqualmie, Skykomish, Pilchuck, & Wallace Rivers Agriculture, Pasture, & Mixed Environs 65.9% Urban & Mixed Environs 33.0% Montane Mixed Conifer Forest 29.5% Subalpine Parkland 2.4% Montane Coniferous Wetlands 1.0% Bays & Estuaries 0.3% Westside Oak & Dry Douglas-Fir Forest & Woodlands 0.0% Lakes, Rivers, Ponds, & Reservoirs -2.2% Alpine Grasslands & Shrublands -5.4% Westside Lowlands Conifer-Hardwood Forest -22.1% Herbaceous Wetlands -49.8% Westside Riparian-Wetlands -53.4%

Results: Terrestrial Habitat

Change in Wildlife-Habitat Types All Chinook Populations in Washington

Results: Estuarine Habitat

Estuarine Habitat Loss and Lambda

Conclusions Amount of remaining estuarine habitat seems important Terrestrial habitat does not appear to be as important

Next Steps Finish estuarine habitat loss assessment Finish assessing terrestrial habitat “condition” at local scale Assess terrestrial habitat “condition” using static categories Run appropriate statistical tests for significance