July 19, 1998
Puget Sound is approaching a diverse, healthier, but less-abundant fish
community. Scientists who in the past suggested that some amount of nutrient
and organic input might be beneficial to the Sound, or at least not harmful,
were discredited by the media, regulatory agencies and public-advocacy
groups. Is it time to take another look at the relationship between organic
matter and fish habitat?
Much of the past focus of Puget Sound has been on sewage treatment, chemical contaminants, dredging and bacteria. The public sees that we have spent billions to control pollution and the result is fewer fish. This contradiction must be frustrating. But it can be resolved by a more open, flexible, "ecosystem-based" monitoring and assessment program. Such a program will give managers and the public new alternatives for management and most importantly, give us more realistic expectations about what "clean water" means and "how clean is clean enough."
How does an "ecosystem" approach work? It looks at everything that might affect the fish, not just pollutants. It explores contradictory ideas, such as those highlighted in the recent articles by Ross Anderson, ("Voyage of Discovery," July 12 and 15.)
For example, protection and enhancement of marine mammals may be cropping
resident fish and shellfish; ocean climate changes may be favoring certain
species at the expense of others and "advanced" treatment of sewage and
pulp-mill wastes may have reduced inputs of organic material to the Sound,
and therefore, reduced the amount of food. Let's see what unrestricted
consideration of these possibilities might lead to.
We are all familiar with Herschel and his gang of California sea lions who pillaged steelhead and salmon at the Ballard Locks. The "Herschels" were sent to Florida but their friends are still consuming large numbers of fish along the coast. Herschel is not alone.
During the past quarter century, the Sound has been home to fast-growing populations of harbor seals. The Sound's seals have been reproducing at record rates, even fouling shellfish beds with their fecal material. What we don't know - but ought to - is what their food habits really are. How much of the Sound's fish and shellfish production are they consuming each year? Which species? We don't know if any agency is answering this question: if they are, the answer is not being used to address the "clean Sound, no fish" contradiction.
What about ocean change? El Ni centsno aside, the North Pacific Ocean has been switching back and forth between several regimes. Each regime lasts several decades. The last big switch was around 1976-77. We're overdue for another (and there are signs it is coming!) These regime shifts result in changing water clarity, water temperature and abundance of plankton - the basic food of baby fish, shellfish and herring. The regime shift has affected the entire Pacific Coast where plankton and fish abundance have been especially low during the past 20 years. Presumably, this is also the case in Puget Sound. Or is it?
To our knowledge, there is no program in place to compare plankton and
fish production in Puget Sound with that in the North Pacific Ocean, to
see if our local problem is actually oceanwide. Ironically, there are such
programs for Alaska's Prince William Sound and the California coast.
During the 1950s and 1960s, when Seattle, Everett and Tacoma outfalls were daily releasing tons of organic wastes into the Sound, bottom-trawlers were reaping a bounty of fish - cod, sole, hake, rockfish and herring. (Fish do not eat the organic matter directly, but do consume the worms, clams and crustaceans that thrive on it).
Salmon were returning in acceptable numbers. To be certain, resident fish in the Duwamish Waterway and other so-called "hot spots" were plagued with fin rot and other diseases caused by chemicals. But fish were abundant, even there. Is it possible the historically high fish production may be due, in part, to the organic material that used to go into the Sound (and now, at considerable public cost, has been renamed "biosolids" and landfilled or purveyed as fertilizer)?
Did that organic wasteload function like the organic matter (called detritus) that used to runoff from the once more-abundant coastal wetlands? As the coastal wetlands were filled (mostly many years ago), the important detritus export diminished but may have been compensated for by societal discharges of organic wastes. With advances in wastewater treatment did we move - like the modern farmer - from organic manure and compost to just chemical fertilizers that only provide the raw nutrients?
Unfortunately, scientists who suggested that some amount of nutrient and organic input might be beneficial to the Sound, or at least not harmful, were discounted by the media, regulatory agencies and public advocacy groups. It was practically illegal to discuss the Sound's "assimilative capacity" for nutrients and organic material and, indeed, any research smacking of that issue was summarily ignored, with one notable exception - Lake Washington.
In his 1991 book, "The Uses of Ecology: Lake Washington and Beyond," University of Washington Professor Emeritus "Doc" Edmundson describes how diversion of treated sewage in 1964 to Puget Sound transformed Lake Washington from a "polluted" but highly productive water body into a clean-looking but less-productive lake. As it got cleaner, it produced fewer fish, including sockeye.
Actually the story is more complicated. Neither he nor the rest of us advocate a return to those days. But to continue to ignore the role of nutrients and organic matter as a factor in increasing native fish production is akin to sticking our collective heads in the mud.
There is a provocative problem with this "sewage was good" idea: our expectation about what is normal. If you accept that there were more fish in the past when pollution was at its peak, the necessary implication is that before industrialization - before the turn of the century - maybe, just maybe, there were actually fewer fish in the Sound - at least marine fish such as sole, flounder, rockfish and cod. Were we harvesting, during the '40s and '50s, an excess of fish raised on waste discharges?
Maybe the normal situation is what we are now approaching: a diverse, healthier (low disease), but less-abundant fish community. We know this happened elsewhere. The abundance of fish around California wastewater outfalls increased 10- to 100-fold during discharge, then crashed as the effluent was cleaned up or outfalls relocated. So, is more fish a realistic expectation for a cleaner Sound? Maybe not!
These are just a few of the possibilities that need to be considered
in a broader view of Puget Sound. There are more: we didn't discuss overfishing,
source control, sediment hot spots, waste sites, oil spills, red tides,
watershed development, etc. Together with marine mammal enhancement, ocean
climate change and organic and nutrient loading, we need to know not only
what roles all these factors play in fish production, but also, on a scale
of 1 to 10, their relative importance!
-- Start with the 1993 National Research Council Report, "Managing Wastewaters in the Coastal Urban Areas," with the fishery-oceanography reports from the California and Prince William Sound programs, "Doc" Edmundson's masterpiece on Lake Washington and the advice from the team's own science advisers.
-- Look at existing conceptual and physical models of the Sound. Re-consider what our ecological and fisheries expectations should be in light of pre-industrial history and data.
-- Mine the "old timers" for their knowledge and their opinions before it is too late to do that.
-- Look at century-long trends: marine mammals, marine birds, wastewater inputs, fish landings, fishing effort, plankton abundance, rainfall, temperature, runoff, El Ni centsno events, regime shifts, wastewater loading, etc., etc.
-- Then use the models to connect the pieces; spend some money testing the new hypotheses and start modeling new alternative management scenarios.
Such a broad focus may not solve all the riddles, but it will greatly reduce our uncertainties and the chance for future surprises. More importantly, it will help make sure that we don't waste billions in public money on false expectations or counterproductive management actions.
There will be a bureaucratic reluctance to admit that some of our management actions may have been counterproductive, so a number of changes that should happen probably still will not for many years to come. If the reader is challenged by these comments, that is exactly our point.
The Puget Sound Water Quality Action Team is on the verge of important
discovery. The team deserves encouragement, support and a broader working
Lincoln Loehr is an oceanographer working as an environmental analyst for Heller, Ehrman, White and McAuliffe, Seattle. He has worked on conceptual modeling of Pacific Northwest ecosystems and on issues associated with wastewater discharges.
Herbert Curl Jr. is a biological oceanographer, now retired from service
with the National Oceanic and Atmospheric Administration. During the late
1970's and 1980's Curl's teams and associates helped develop and test models
for managing contaminants in Puget Sound.