Shoreline Science

For many, understanding the environmental issues of South Puget Sound’s important shorelines is a bit difficult. Harry Branch, who has a master’s degree in Environmental Studies, has written an excellent letter to the Thurston County Commissioners describing the issues. He has done an great job of describing the situation in a language that is easier for the non-scientist to understand.

We present Harry’s letter below:

Letter from Harry Branch to Thurston County – Aquaculture/Shoreline Development

The County is correct that geoduck farming on area beaches is Shoreline Development. Any alteration of structure that impacts ecological function is development.

Taylor Shellfish has put forth a number of studies claiming that water quality, the marine food chain, water circulation and native species will not be effected by expanded shellfish cultivation. Studies also claim that increased shellfish production will remove a large percentage of the nitrogen introduced into the environment by humans. Nitrogen is suggested to be a major water quality problem by over-fertilizing algal blooms that die off and create anoxic conditions.

Nitrogen and sunlight are also the essential building blocks of life. Nitrogen is utilized by phytoplankton (primary production) which is then consumed by  zooplankton and so on up the food web.  This happens best in shallow water with persistent patterns of circulation, the basic estuary. In South Puget Sound we've altered three out of four estuaries (don't forget the streams). Often the entire estuary is fed through a long pipe and dissolved oxygen and other basic parameters take a dive. The problem as often as not is changes in structure to tide flats, salt marsh and the upper beach rather than the introduction of too many nutrients. (See the spring edition of Green Pages for a more in-depth look at this question).

Shellfish don't eat nitrogen, they eat phytoplankton that has consumed nitrogen. Because phytoplankton reproduce rapidly, there is only a temporary lag in abundance. Taylor's studies thoroughly evaluate the potential effects on phytoplankton abundance spatially, seasonally and diurnally. The limiting factor in a typical system is primary production. The rationale is that by assessing the impact on primary production we can predict impacts on the entire food web.

Well, that's poppycock. Mussels don't just eat phytoplankton, they eat zooplankton, from tiny protozoa that mimic phytoplankton to larger fish larvae, tiny insect-like babies that will become larger fish, crabs, barnacles and so on. Nearly all fish consume zooplankton during their larval phase and some fish continue to do so their entire lives. A single herring may consume thousands of copepods in a single day. Larger zooplankton are important food for forage fish and growing fish larvae. They link primary producers with larger, higher tropic level animals. Because zooplankton reproduction tends to lag phytoplankton reproduction, the reduction in nitrogen contained in phytoplankton is probably more than offset by a reduction in herbivores such as copepods. Copepods, probably the most plentiful creatures on earth, are the natural control for phytoplankton; they maintain balance in the system. The only benefit of large scale shellfish cultivation, if one can consider it a benefit, is that phytoplankton, herbivores and secondary consumers, i.e. everything, is reduced.

Shellfish cultivation on area beaches without doubt impedes a host of important ecological processes including forage fish spawning. Virtually all native species, from ghost shrimp to macro-algae to diving ducks, are considered pests. This modus operandi runs antithetical to Ecosystem Based Management, the direction we are and must be heading.

Taylor suggests that water quality in Totten Inlet has been impacted by, among other things, humans over-harvesting shellfish. Since we haven't been assessing dissolved oxygen for very long, this theory is entirely conjecture. Concerning the most basic, physical parameters, Totten Inlet like much of Puget Sound and Hood Canal is a fjord. It's perfectly natural for the water column to be stratified and anoxic below a certain depth.

Taylor could make a better case that by over-harvesting resources and altering the structure of Puget Sound through dredging, filling and destroying almost all our estuaries, we damaged the ecosystem and shellfish growers are only filling an empty niche. But this would be a very disjointed weak argument as well. The sustainability of an ecosystem comprised of three kinds of bivalves is doubtful at best. Compacting and biological sameness create an environment where diseases can easily spread. Outside influences such as acidification pose additional risks. And if any species crashes there may be nothing to replace it except bacteria and perhaps jellyfish.

We don't know the economic potential of all the fisheries that could be developed through restoration and enhancement of Puget Sound's natural ecosystems. It seems likely that rockfish, flatfish, salmon, herring, smelt and shellfish in combination would be marvelously productive. Sadly, estuarine and nearshore structure continues to suffer the woes of development. But this is no reason to allow shellfish cultivation to completely ruin what's left. "Geoduck farm" sounds so benevolent. But this isn't anything like farming. If anything we're talking about feed lots.

My family owned the oldest vineyard in the State on Stretch island. They're house and my aunt's house next door overlooked Puget Sound. Not that long ago we could net herring and smelt with a rake, filling a small boat in short time. My father caught a 46 pound lingcod virtually off his front porch. Not these days. The beach was beautiful and enjoyed by all. I don't know if it is now covered with PVC and netting. If I find out that it is, my heart will sink. It must be very sad for people who live on the waterfront to have to witness this assault. If this isn't shoreline development, I don't know what is.

Thank you Thurston County for standing your ground on this important question. If I can be of any assistance, please let me know.

Harry Branch

Harry's Background

Harry Branch has a Masters Degree in Environmental Studies with a focus on marine reserves as a tool in fishery management. He has also served as a captain operating research vessels for agencies like NOAA. He's worked on sea otter catch and release efforts, bioassays, bird counts and other live science.