Keynote speaker at Sound Waters 2010
Dr. Nathaniel ‘Nat’ Scholtz, NOAA/NWFSC
Coho salmon are our first choice for a ‘sentinel species’ because they:
- are widely distributed
- inhabit lowland steams that are important and familiar to humans and areas impacted directly by stormwater runoff (if we can reduce toxics in lowland streams, then we’ll likely keep them out of the marine environment, so may solve problems for rockfish, lingcod, and other marine species).
- live >1 yr in freshwater, so are exposed to stormwater at multiple life stages (adults, eggs, juveniles)
- are supported by a diverse food web
- are sensitive to water quality and quantity
- are a species of concern under the ESA (only listed local species are chinook and southern resident killer whales)
- provide an accessible narrative to the public, exemplify an ecosystem-based approach to stormwater management
Research results
- Longfellow Creek (urban W Seattle) experimental facility
- Urban runoff is toxic to coho embryos (in streams and in lab)
- For juveniles, the problems are in the foodweb (macroinvertebrates from Cedar River are happy in Longfellow until a storm because they are very sensitive to toxic runoff). The bugs leave or die, reducing food for juveniles and impacting salmon mortality.
- Copper (common in brake pads) is specifically toxic to the salmon nose (Science News “descent of smell; pollution imparis olfaction”). This impairs their ability to imprint on their home stream and avoid predators (attacked fish release a pheremone upon mechanical damage that causes downstream juveniles to freeze). Predator-prey studies on the Olympic Peninsula shows juvenile coho suffer greater mortality from cutthroat trout when exposed to copper.
- Over last 9 years, we’ve observed very high (40-90%) pre-spawn mortality of adult coho (full of eggs) in urban streams throughout Seattle. Extinction projections don’t look good and they don’t yet include possible future pressures: further human population growth (with pursuant urban development) and climate change (drier summers with more intense rains, implying more toxic stormwater events).
Solutions to the stormwater challenge:
- Pervious pavement in Pringle Creek Community
- NOAA Bay-Watershed Education and Training funding (translating research to education and service-learning)
- Local example: Service, Education, and Adventure (SEA) and Edmonds Community College Learn and Serve Environmental Anthropology Field (LEAF) School
- Salmon-Safe Certification (Nike Ad and PCC labels) — developing local incentives for pollution reduction using NOAA research findings
- Evaluating effectiveness of low impact development (LID) — partnership with Washington State University Puyallup Extension Campus at its new research facility (experimental plots)
- About 8% of Seattle is re-developed every year! Seattle street vacuums are being tested. SEA street retention of stormwater is ~98%!
- HB 3018/SB 6557: Limiting the use of copper and other substances in brake pads
- Personal actions: support outdoor education, Puget Sound farms, and look to Puget Sound for optimism (Southern CA is much worse!) — see Florian Graner’s high-definition video on underwater Puget Sound.
Questions:
- Why can’t we just filter all the streams? We could (it works on Longfellow Creek), but it’s one step from a dialysis machine — it’s prohibitively expensive.
- There is also legislation under assessment re: mercury in lighting, and other marine issues. How does the public know about activism opportunities?
- What should we do about pollution from a local golf course and farms? That’s the purview of the Department of Ecology. Unfortunately, State standards and rules lag our research on many contaminants. Thank goodness we have the Federal precedent of the Clean Water Act.
- How does the 34M gallons/year of raw sewage from Victoria affect Puget Sound water quality? I’m not sure, but would be concerned about new contaminants of concerns and pharmaceuticals. We’re seeking funding to use mussels around Puget Sound as indicator species.
- Why is it better to have runoff going into ground? How long before the ground becomes contaminated? Using copper as an example, many contaminants bind to clay and are pulled out of harms way.
- Are those movies you were going to show available on line. Yes on our web site.
- Are the street vacuums effective? Though Seattle didn’t put metals on the streets, they’re responsible to Dept. of Ecology. They can tell us how much they take off the streets; we’re working with them to determine what is left on the street.
- Is there any way to make impermeable surfaces permeable, like with a street drill? I’m not sure, but would worry about the ability of the roads to take their engineered loads.