By C. Ronald Franks
The oyster. Nothing is so intrinsically tied to the image of a healthy Chesapeake as this, undoubtedly Maryland's favorite bivalve. Back in the days when oyster harvests were high, the Bay was considered in pristine condition; as the 20th century drew to a close and their numbers plummeted, reports of the Chesapeake's ills became the norm. The native oyster is, unquestionably, the most prominent indicator of the health of our waterways.
Wherever you turn these days, the plight of the native oyster and the possible "encroachment" of a new species into Bay waters seem to be the topics of animated conversation. A generation has now come of age in an era where oysters must be imported to Maryland from out of state to satisfy holiday culinary demands, and old timers wax poetically about how they were once so prolific, they were known as "Chesapeake White Gold."
Today the Bay's oyster industry is economically extinct in spite of tens of millions of state and federal dollars spent on research and restoration projects, thereby impacting harvesters, processors, shippers, restaurants and even entire communities. Last year Maryland's harvest was 25,000 bushels, a significant drop from the previous year's record low of 53,000 bushels and a vestige of the average 2.5 million-bushel annual harvest during the 1970s. The dockside value of Maryland's oyster harvest was in excess of $40 million in 1975; it generated a mere $500,000 in 2003-04.
But aside from the rather immediate issue of oyster harvests, the fact remains that, without the presence of the bivalve in the Bay, we cannot succeed in our plan to return it to optimal health. Our native oyster, Crassostrea virginica, was once considered the Chesapeake's keystone species, serving as a primary contributor to its filtration system and providing rich habitat for many other species. These ecological services, including that of removing nitrogen, a major Bay pollutant, have now declined to nearly imperceptible levels.
Maryland Governor Robert L. Ehrlich, Jr. is committed to restoring the Bay and reversing the long-running decline in its water quality. However, total and successful restoration relies on three equally important and interrelated elements: the return of bay grasses, curbing the flow of nutrients and other pollutants into the Bay, and the recovery of the oyster population.
While current native oyster restoration efforts in low salinity areas are showing some short-term, site-specific benefits, there is little evidence progress is being made on a Bay-wide level. Oyster abundance is currently estimated to be less than one percent of historic levels and 50 percent less than what it was just 10 years ago. The oyster parasites Dermo and MSX have decimated populations in 90 percent of the Bay, and unless these diseases can be substantially controlled - and no evidence suggests they can - the outlook for C. virginica is bleak. To add insult to injury, the siltation of thousands of acres of oyster beds has accelerated coincidentally with the decline of live oysters.
With no strategies to significantly minimize the impacts of disease, native oyster restoration efforts across most of the Bay will continue to flounder, resulting in a continued degradation of its ecological functions, decline of the fishery and erosion of the waterman's traditional culture.
A Crossroads in Restoration Efforts
In the face of these disturbing statistics, a new oyster holds promise for the Chesapeake. Commonly known as the Asian oyster, Crassostrea ariakensis is larger, grows at the same rate or faster than the native species, and seems resilient to MSX and Dermo. But introducing a new species to our fragile ecosystem poses its own share of risks. And here is where we find ourselves: Is it better for the State to continue on its current course of trying to rebuild native oyster stocks, or is it time to consider another species to help speed restoration and recovery efforts?
The Department of Natural Resources (DNR) has been leading the call to study the introduction of the nonnative oyster to Bay waters. Scientists from the world over have been conducting research on C. ariakensis for years. Our experience with the bivalve has shown that it can not only survive in our waters but also carry out the functions that the native oyster, when in abundant supply, once performed - most notably, filtering the Bay's waters of accumulated nutrients and algae, and improving water clarity and oxygen levels, thereby allowing other living organisms such as bay grasses to thrive.
The State of Maryland has funded almost $2 million in new research on nonnative oysters in cooperation with the State of Virginia, federal agencies and the Oyster Recovery Partnership (a coalition of organizations, institutions, businesses and individuals dedicated to helping restore the health of the Chesapeake by restoring the Bay's oyster population). Research is currently focused on a dozen areas, including:
- Is the non native oyster a threat to the native species?
- If introduced, would a nonnative oyster overwhelm the native species?
- Does the nonnative oyster carry pathogens, parasites and diseases that can harm the Bay?
- If introduced, will the nonnative oyster expand beyond the Chesapeake Bay?
The Science of It All
These questions are being addressed and evaluated as part of an Environmental Impact Statement, or EIS, currently being studied by scientists and officials representing the states of Maryland and Virginia (federal agencies and congressional representatives have also been asked to assist throughout the process). This EIS presents an open forum to discuss the issues and science surrounding oyster restoration, and a landmark opportunity to identify the ecological risks and benefits that must be addressed when considering the introduction of a nonnative oyster, as well as the future of C. virginica.
The ultimate goal of the EIS is to evaluate eight oyster restoration proposals and identify a strategy and subsequent actions that will successfully re-establish a population in the Chesapeake to a level of abundance comparable to those between 1920 and 1970, a period of stability and minimal parasites.
Four of the proposals being reviewed are based on native oysters and range from imposing a moratorium on their harvest to establishing and expanding aquaculture operations. The most controversial proposal surrounds the controlled introduction of a strain of C. ariakensis that has been in Oregon waters for over 30 years. (While this particular strain has been certified pathogen free by two internationally certified laboratories, the University of Maryland's Center for Marine Biotechnology continues to conduct additional research and disease and virus scans.) The introduction of C. ariakensis from hatcheries is proposed to occur first on state-designated sanctuaries, where harvesting would be prohibited permanently, and later in special management areas where only selective harvesting would be allowed.
In early 2005, Virginia and Maryland will convene an independent oyster advisory panel comprised of representatives from some of the leading national and international universities, laboratories and research facilities to determine if the results of the EIS provide enough evidence to make a decision regarding a preferred alternative. If in the panel's view, the science is lacking, and/or questions are unanswered, the necessary additional time to complete the work will be given.
Assessment information will be incorporated into the draft EIS by March 2005. The document will then be referred back to the states' to decide if there is adequate information to proceed with a restoration proposal, or if more time and research are needed to adequately evaluate the issue. If a preferred strategy is identified, a draft EIS is expected to be made available to the public in May 2005. Based upon public input, officials will decide whether or not to proceed with a final EIS in June 2005, and if so, announce a Record of Decision in July 2005.
To Err on the Side of Caution
In the meantime, the States are continuing C. virginica restoration efforts with the Army Corps of Engineers throughout the Bay, using the best available restoration strategies and stock assessment techniques. Although efforts in low salinity areas are showing some short-term, site-specific benefits, there is little evidence progress is being made on a Bay-wide level. It is imperative that future oyster restoration efforts must address the entire Bay and not just the improvement of a few sites.
The bottom line is, Maryland and Virginia have agreed they will not proceed with the introduction of a nonnative oyster if the dangers outweigh the potential benefits. Governor Ehrlich is committed to restoring the health of the Chesapeake Bay, not endangering it. Our decisions will be based on sound science and analysis and we will NOT proceed with any introduction of C. ariakensis, or any nonnative oyster, into the Bay if there are unacceptable risks.
The states can no longer rely on the tried and true in the hopes of rebuilding the Chesapeake's decimated oyster stocks and returning its ecosystem to balance. Obtaining a level of vitality and functionality that hasn't been seen in nearly 35 years is a daunting challenge in itself, considering the spectrum of proposals and parties involved. To accomplish such a task will require ingenious thinking, innovative technologies, and political will through the complete and total commitment of interstate public and private partnerships. You can rest assured that here in Maryland we are making this effort our number one environmental priority.
This article is the fourth in an ongoing series about Maryland's Bay Restoration efforts.
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