Salmon Bay Natural Area: Restoration Monitoring

UW School of Aquatic and Fishery Sciences

Jason Toft

Funding and Support: King Conservation District and Seattle Public Utilities

• Brief introduction to SBNA • Background data • SBNA monitoring

• Invertebrates (aquatic, insects) • Fish, prey items

• Summary, future steps

Outline

How fish assessments can be used to help

“build restoration projects”.

Fish utilization:

• Prior to restoration – Inform goals

• During project design – Incorporation of data

• Monitoring restoration – What works, what doesn’t

Data strengths: Optimized when there’s a focused experimental

design, precise data.

Data weaknesses: Natural variability, issues of time and space.

Make sure you’re not comparing apples and oranges.

The Role of Science in Restoration

• Construction of the Locks

has created a urbanized

mini-estuary

• Freshwater zooplankton

are prevalent throughout

the Inner Bay

• This small osmotic-

transitional zone should be

the focus of restoration

2001 Shilshole

Study Conclusions

2003 Habitat Measurements: Shoreline armoring truncates the shallow water zone, gradual slope is lost. Pelagic fish that are typically spread-out along a large intertidal area must inhabit deep water directly along shore, and avoid swimming under piers.

Toft, J.D., J.R. Cordell, C.A. Simenstad, and L.A. Stamatiou. 2007. Fish distribution, abundance, and behavior along city shoreline types in Puget Sound. North American Journal of Fisheries Management 27:465-480.

Diet Analysis: Juvenile Chinook prey less on terrestrial insects at sites with armoring.

Before – 2004 After – 2010

Pre and Post-Restoration Monitoring - 2004, 2010, 2012: 1. Benthic aquatic invertebrates 2. Terrestrial insects 3. Fish sampling 4. Beach sediments

Salmon Bay Natural Area Removal of the house and pier structures, and restoration of the beach and shoreline vegetation.

Benthic invertebrates, Low tidal elevations – Area at floating dock

*** Restoration increased numbers and taxa richness

Insects, shoreline vegetation – Area at balcony of house

*** Restoration increased numbers and taxa richness

Fish, snorkel surveys 2004 – Juvenile salmon distributed around edges

2010 – Juvenile salmon evenly distributed

Fish diets 2012 – Large freshwater signature

Summary Monitoring data shows improved values of most measurements compared to pre-restored and reference beach.

1. Nursery area for fish

2. Foraging opportunities

3. Riparian value

4. Connectivity

5. Physical resilience

Toft, J.D., A.S. Ogston, S.M. Heerhartz, J.R. Cordell, and E.E. Flemer. 2013. Ecological response and physical

stability of habitat enhancements along an urban armored shoreline. Ecological Engineering 57:97-108.

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