Download Debate 2 – Exotics Species and the Chesapeake Bay Group C

Debate 2 – Exotics Species and the Chesapeake Bay
Group C – Stop Harvesting
Research Paper
Kinsey Hoffman, Elizabeth Hincker, Travis Worrell
NAV 2554 Spring 2011
INTRODUCTION
When John Smith first came to the Chesapeake Bay in 1608, the oyster reefs that
he saw “lay as thick as stones” – so thick that they made even navigation difficult
(Economist). This is far from the image of the Chesapeake Bay today; the oyster
population in the Chesapeake has dropped “99 percent below historic levels, because of
overfishing and a pair of diseases” (Fahrenthold). The oysters are a fundamental species
to the Chesapeake Bay ecosystem, and their deterioration has had significant effects on
the environment. A lack of oysters, which occupy a niche as a water filterer, has caused a
dramatic decline in water quality in the Bay. Drops in the number of oyster reefs also
eliminate the habitats of many other species. The plummet in the number of oysters
affects the surrounding human population as well. Many people who live right near the
Chesapeake Bay rely on the harvesting and selling of oysters as a source of income.
Without this quintessential species, watermen who harvest and sell oysters at local
markets or to local restaurants will lose their jobs.
In the latter half of the 20th century, the population of the Chesapeake Bay
watershed doubled. This increased fishing demand on the oysters at a time when higher
human populations were increasing pollution loads on the Bay. The oyster diseases MSX
and Dermo were discovered in the Bay in 1959; these parasites spread rapidly though the
population killing many oysters in the process. This compounding of factors caused
oyster populations to greatly decline.
These factors that led to such a large decline in the oyster population affected
many aspects of the environment and the humans that live off the Chesapeake Bay. The
great reliance on oysters in the Chesapeake Bay ecosystem creates an urgent need to
restore the population levels of this valuable species. At this point in time, many people
are ready to give up on the eastern oyster. One proposed solution is to introduce a foreign
species of oyster into the Chesapeake Bay – Crassostrea ariakensis. This species comes
from Japan, and is more commonly called the Asian, Pacific or Suminoe oyster. Based on
preliminary studies conducted on C. ariakensis in the Chesapeake Bay, the advocates of
the Pacific oyster believe that it will restore the natural filter of the Chesapeake Bay,
create habitats for other organisms, and provide a source of food and jobs for humans that
live near the Chesapeake Bay. We explore to what extent the indigenous eastern oyster,
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C. virginica, is more suitable to support the organisms and humans that rely on the
Chesapeake Bay ecosystem than the foreign species of Asian oyster, C. ariakensis.
IMPACTS ON SURVIVAL
Many studies have been conducted by environmental organizations to test and
analyze how successful the potential introduction of C. ariakensis into the Chesapeake
Bay would be. These studies should be continued in the future to see the long-term
outcomes, but the preliminary results are what are needed at this point in time in order to
make a decision regarding the Asian oyster’s potential to effectively sustain the
Chesapeake Bay ecosystem. Results from an experiment testing single-species treatments
and mixed-species treatments at four different sites in the Chesapeake Bay show the
projected effects of such abiotic and biotic factors on the oysters’ growth. One of the
overarching discoveries was that, on average, the Asian oyster tends to grow larger and
faster than the native species. According to Kingsley-Smith et al. “eight months after
deployment C. ariakensis were significantly larger than C. virginica at all sites.” This
general trend continued throughout the duration of the experiment. Each of the
independent variables had an impact on the survival of the oysters. The variables tested
included salinity, tide, predation, and disease.
ABIOTIC FACTORS
The first abiotic factor that has an effect on the oysters’ growth is salinity of the
water. The findings from this experiment reveal that salinity plays a role in which species
the environment favors; the study found that high salinity in the subtidal region proved to
be more suitable for the Pacific oyster than the native oyster. Also, the salinity affects the
intensity of the diseases that plague the waters of the Chesapeake Bay. According to
Kingsley-Smith et al, “in C. virginica, moderate and high intensity infections were only
common at the two higher salinity sites.”
Another abiotic factor that affects the growth rate of both species of oysters is
aerial exposure, which is based on the rising and falling tides . A study published by the
National Shellfisheries Association investigated the effects of aerial exposure on survival
rates of the native oyster and the Asian oyster. The two species were placed in four
different sites that varied in the aerial exposure they received. The results of this study
show that C. virginica have a much higher survival rate in the two middle regions on the
spectrum, mid intertidal and low intertidal, that received two hours of emersion and one
hour of emersion, respectively. After one week, neither species survived in the high
intertidal group that received 3.5 hours of emersion. Both species had the highest survival
rates in the subtidal treatment, when they were fully submerged under the water. C.
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ariakensis grew faster in this subtidal group than C. virginica. Also, in this study by
Kingsley-Smith, “C. ariakensis displayed broad environmental tolerances, often
exceeding native oyster survival and growth rates” in subtidal habitats.
From this data, the conclusion can be drawn that if the Asian oyster was
introduced into the Chesapeake Bay, they would be restricted to locations where they
were completely submerged under water. The Asian oysters could displace the native
oysters from subtidal regions because the Asian oyster grows faster than the eastern
oyster in these areas. This replacement of the eastern oyster in certain environments has
the potential to completely alter the equilibrium that has been established over the years
amongst the interacting native species.
PREDATION
A biotic factor that heavily relies on the formation of oyster reefs is predation.
One of the main predators of oysters in the Chesapeake Bay is the human population, and
oyster reefs are critically important to the success of the oyster harvesting industry. As
well as helping the population to grow the aquatic reefs provide for convenient methods
of harvesting. The two most common techniques for harvesting are tongs and dredges.
Tongs look like two garden rakes with very long handles, ranging from about seven to
twenty four feet long, “with the tooth-side of each rake facing each other.” (“Oystering
Methods”) The watermen who use these tools, called tongmen, scrape the reefs and the
shallow waters while in small canoes or skiffs, thus only enabling harvest in the
Chesapeake Bay in temperate weather. Tongs also can only be used in shallow water
beds, because they cannot reach very far down, but they are much less harmful to the
environment than the alternative method of dredging.
Dredges are a more effective but more damaging means of harvesting oysters.
This device consists of iron rings linked together to form a mesh bag, the mouth of which
is supported by a metal frame that is attached to a winch in the boat by a long chain in
order to lift the bag up. Along the bottom of the frame is a bar with sharp iron teeth that
scrape the oysters across the bottom of the Bay and guide them into the bag. (“Oyster
Wars: Oystering Methods”) This tool was originally used by watermen in areas of the
Bay that were too deep for using tongs, but because the dredges can collect many more
oysters, the watermen began to use them in shallow waters also. There were two
problems with this; one, the dredges also scraped up other organisms and ruined the
bottom habitats, and two, the tongmen and dredgers had to compete over the areas that
they were harvesting. The devastation caused by the dredges often completely destroyed
oyster beds, which prevented the formation of oyster reefs and therefore reduced the rate
at which the oysters could replenish their population.
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Although there are problems with each of these strategies for harvesting oysters,
the structure of an oyster reef makes the effects of such tools less damaging to the
environment. If these tools can scrape across the top or sides of an oyster reef, then the
fragile habitat along the bottom is not harmed. This protects the plants and the bottom
dwelling organisms. Also, this opens up more availability of hard surface area of oyster
shells that the oyster spat need to land on in order to successfully grow.
DISEASE
A second biotic factor that affects the oyster population is parasitic diseases. The
two most prevalent diseases in the Chesapeake Bay are Haplosporidium nelsoni and
Perkinsus marinus, more commonly known as MSX and Dermo respectively. According
to the MSX fact sheet released by the Virginia Institute of Marine Science “The disease
can affect all ages of oysters, spat to adult. Infections are acquired through gill and
mantle tissue, and can rapidly spread throughout the oyster”. Preliminary, short-term tests
have been carried out to see how the Pacific oyster reacts to these aggressive diseases,
because MSX and Dermo cause significant restrictions on the native oyster population.
The Pacific oyster is susceptible to the same diseases as the eastern oyster. The Pacific
oyster can contract and develop Dermo, just like the eastern oyster, but just at different
stages in their development (Paynter). Additionally, the native oyster is becoming more
disease resistant to both MSX and Dermo. (“2008 State of the Bay”) The life spans for
the native oyster are becoming longer.
The Asian oyster is also susceptible to another parasite, Bonamia. This parasite
exists in Atlantic waters, including the Chesapeake Bay. In a single trial, infection rate
was 90% for the Asian oyster, while only 20% for the eastern oyster. This raises serious
doubts of the oyster’s ability to survive Atlantic conditions. (Luckenbach)
COHABITATION
The study by Kingsley-Smith also scratches the surface of the exploration of
whether the two species of oysters can cohabitate successfully. One of the changing
variables in the experiment was whether the group of oysters was single species or mixed
species According to Kingsley-Smith et al, “At low and mid salinity subtidal sites, C.
ariakensis shell heights were significantly greater in the single-species treatment
compared with the mixed-species treatment.” The Asian oyster thrives in areas where
there are no eastern oysters growing alongside them. In the mixed-species treatments, the
eastern oyster grows up and around the Asian oyster. This biotic relationship helps to
determine whether the Asian oyster should be introduced, based on whether it would
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harm or help the native species. From this research, one can conclude that although the
eastern and Asian oysters do not kill each other, the presence of one species of oyster is
not beneficial to the other species.
REEF FORMATION
One important role that the native oyster fills in the Chesapeake Bay ecosystem is
establishing oyster reefs, created by oysters growing upon each other in layers to form a
hard surface over the bottom. These structures, which the native oysters naturally grow
in, act as a protector of the biodiversity in this environment. Oyster reefs provide habitats
for other aquatic species, provide a place for oyster spat to grow, and improve water
quality. Many game and commercial species such as white perch, striped bass, and blue
crabs rely on the reefs for breeding grounds and refuge. The oyster reefs provide a hard
surface necessary for oyster larvae and other invertebrates like sponges and barnacles to
latch onto and grow. The bottom of the Bay mostly consists of soft sediment, so the
oyster reefs help these young organisms reach adulthood. (“Aquatic Reefs”)
Based on studies by Luckenbach et al, C. ariakensis does not form reefs like C.
viginica. In such studies, it has been shown that C. virginica grows up and around C.
ariakensis when growing in the same space in the structure of reefs. (Luckenbach) The
Asian oyster will not form reefs as quickly as C. virginica, which is a problem because
oyster reefs are vital to the restoration efforts within the Chesapeake Bay.
ECONOMIC CONSEQUENCES OF INTRODUCTION
Despite larger quantities of oysters that may become present upon introduction of
the foreign species of oyster, this may not be an entirely good thing. Customers may not
want to buy foreign oysters because it is unfamiliar. People do not always like change,
especially consuming something unknown. Perhaps this new species of oyster is unsafe,
or tastes different. According to some, the Asian oyster has a metallic taste when eaten
raw. Even if this taste is not a bad taste, it is still different and unexpected, and not
everyone embraces change.
PROPOSED SOLUTION
Our proposal for a solution is to create specific no-take zones and rotating zones
available for harvest. The reason why we were getting such good harvest of fish 200
years ago is because we couldn’t fish anywhere. Increases in technology and fishing gear
allow us to fish everywhere. Fish have nowhere left to run, and nowhere left to
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reproduce. Leaving a safe-zone allows reproduction to occur without disruption. Also,
rotating the zones that fishermen can harvest in would allow certain areas to recover
while still allowing fishermen to collect a harvest.
In order to carry out such a proposal, regulations would have to be placed on the
Chesapeake Bay fishermen and consumers of oysters. Strict penalties and enforcement
would have to be put in place. The government would need to be the ones to put
regulations in place. There also needs to be an element of education incorporated into this
restoration effort; fishermen need to acknowledge that oysters are a finite resource. For
areas that have rotating harvest seasons, aquaculture should be used to reseed the oyster
beds. This also will help evolution run its course – an expensive method but oysters
resistant to disease are needed to replenish the population.
ADVANTAGES AND DISADVANTAGES
One of the most significant disadvantages of this proposed solution is the loss of
jobs. Many fishermen will be put out of business and local economies such as restaurants
may suffer. The purpose of this solution is to restore the oyster populations so that we can
save such businesses. Some local economies may have to take a large hit in order to
ensure that we have the availability of these resources for future generations of
businesses. Those out of jobs can look to other related industries for work, such as
aquaculture.
Another disadvantage is that this project will be expensive. However, any
possible solution will be expensive. Introducing the Asian oyster will require the
shipment of enough oysters to create a viable breeding population, which could approach
a few hundred thousand individuals. Many individuals will also need to be introduced to
guarantee enough variety in the species to ensure survival of as many oysters as possible.
In comparison to the entire federal budget, we are currently spending an insignificant
amount of money on restoration efforts for the eastern oyster.
The advantages for the future outweigh the immediate disadvantages. In the short
term, there will be increased business in aquaculture, and the long term effects will
mobilize the restoration of past levels of oyster harvesting. Reestablishing the large
oyster populations will also purify the water and help fight high levels of pollution. The
eastern oyster’s ability to form reefs will create more habitats for blue crabs, striped bass,
and diamondback terrapins, all additionally struggling populations. “Oyster reefs attract
some of the highest densities of fish of any type of habitat in the Bay, helping to support
vibrant recreational fisheries.” (“Aquatic Reefs”) This could foster an increase in
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recreational fishing companies, and attract more tourism to the area, offering even more
economic opportunities for local economies.
CONCLUSION
In conclusion, the Asian oyster seems to be better able to support the immediate
economic and environmental situation of the Chesapeake Bay than the native eastern
oyster. However, given the intertwining abiotic and biotic factors of the Chesapeake Bay,
long-term effects of the Asian oyster in the Chesapeake Bay still need to be studied.
Despite the short-term benefits of this nonnative species, the eastern oyster seems to be
the better choice for the long term, because of its ability to create reefs and provide a
habitat for other economically important native species. Although the projected outcome
seems positive, it is important to recognize the possible negative consequences as well
before making the monumental decision to introduce a foreign species. Once introduced,
the results are irreversible. It is virtually impossible to remove all traces of a species from
a watershed of over 64,000 square miles, especially from an aquatic ecosystem. The longterm effects of introducing foreign species of oysters into the Chesapeake Bay are
unknown and it is too dangerous to risk this entire ecosystem and the humans that live off
this ecosystem.
It is more environmentally friendly to place a larger magnitude on the long-term
effects that will promote a sustainable ecosystem for the future. More efforts should be
put into restoring the eastern oyster before the decision is made to introduce a foreign
species. Funds directed toward restoring their population can be drastically increased
from what they already are, and additional laws can be passed to help protect the oysters.
The emphasis should be placed on caring for this native keystone species first, before
trying to alter the entire ecosystem.
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Annotated Bibliography
Kingsley-Smith, Peter R., et al. "Survival and Growth of Triploid Crassostrea
virginica (Gmelin, 1791) and C. ariakensis (Fujita, 1913) in Bottom
Environments of Chesapeake Bay: Implications for an Introduction." Journal
of Shellfish Research 28.2 (2009): 169-184. Abstract. BioOne. National
Shellfisheries Association. 29 Apr. 2009
<http://www.bioone.org/doi/abs/10.2983/035.028.0201>.
This is an abstract of a study conducted in four different locations in the Chesapeake Bay
watershed to test survival rates of C. ariakensis and C. virginica in different conditions
varying in salinity, tidal patterns and water depth, disease pressure, and predation. The
main findings that pertain to the research question are that C. ariakensis has a lower
survival rate in intertidal areas but outperforms C. virginica in subtidal regions. Also the
two species are not as successful when together, as C. ariakensis grows much better when
in a group of oysters of just that species.
Luckenbach, M. W., and P. R. Kingsley-Smith. "Post-Settlement Survival and
Growth of the Suminoe Oyster, Crassostrea ariakensis, Exposed to Simulated
Emersion Regimes." Journal of Shellfish Research 27.3 (2008): 609-618.
Abstract. BioOne. National Shellfisheries Association. 28 Apr. 2009
<http://www.bioone.org/doi/abs/10.2983/07308000(2008)27%5B609:PSAGOT%5D2.0.CO%3B2>.
This is an abstract of a study conducted in the Chesapeake Bay that tested the survival
rates of C. virginica and C. ariakensis in four groups that varied in the aerial exposure, or
amount of time exposed to the air above the surface of the water, they received. The
findings of this study show that C. virginica have a much higher survival rate in the two
middle regions, mid intertidal and low intertidal, that received two hours emersion and
one hour emersion, respectively. Neither species survived in the high intertidal group that
received 3.5 hours of emersion, but both species had the highest survival rates in the
subtidal treatment, when they were fully submerged under the water. Surprisingly, C.
ariakensis grew faster in this subtidal group than C. virginica. These results show that if
the Asian oyster was introduced into the Chesapeake Bay, they would be restricted to
locations where they were completely submerged under the water, which is atypical of
common conditions of the Chesapeake Bay in the summer.
“Oyster Diseases of the Chesapeake Bay - Dermo Fact Sheet.” 8 Dec. 2005.
Department of Environmental & Aquatic Animal Health, College of William
& Mary. 27 March 2009.
<http://www.vims.edu/research/departments/eaah/programs/shellpath/Researc
h/perkinsus_marinus/index.php>.
This fact sheet provides background information and data about the oyster disease
Dermo. It includes origin, locations, and history, as well as characteristics of the disease.
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“Oyster Diseases of the Chesapeake Bay – MSX Fact Sheet.” 8 Dec. 2005.
Department of Environmental & Aquatic Animal Health, College of William
& Mary. 27 March 2009.
<http://www.vims.edu/research/departments/eaah/programs/shellpath/Researc
h/msx/index.php>.
This fact sheet, like the one above about Dermo, provides information about another
oyster disease called MSX. This will help me make analyses about the effects of such
diseases on the native and foreign oyster species. One important factor of the disease is
that the common time of infection in the Chesapeake Bay is usually from mid-May to
October. It affects the gill and mantle tissues, and spreads rapidly through the oyster. This
source also discusses the prime temperature and salinity for infection of the oyster.
Paynter, Kennedy T., et al. Crassostrea ariakensis in Chesapeake Bay: growth, disease
and mortality in shallow subtidal environments. 2008. Rpt. in Journal of
Shellfisheries Research. Vol. 27. N.p.: n.p., n.d. 509-515. 9 Mar. 2009
<http://findarticles.com/p/articles/mi_m0QPU/is_3_27/ai_n25486003/pg_2?ta
g=content;col1>.
This journal reports the methods and results of an experiment that compared the growth
of C. virginica and C. ariakensis in several locations of the Chesapeake Bay watershed.
Each cage of oysters was also infected with P. marinus, which is more commonly known
as Derma. It reports the effects of the disease on each species of oyster, and goes in depth
on the specific stages of the oysters’ age that the disease is present.
"Aquatic Reefs." Chesapeake Bay Program. 15 Feb. 2008. 4 May 2009
<http://www.chesapeakebay.net/aquaticreefs.aspx?menuitem=14644>.
This web page is a part of the website for the Chesapeake Bay Program, an organization
with the purpose of educating the public about the Chesapeake Bay and what we have to
do in order to protect it. This specific page centers on aquatic reefs, or oyster reefs, which
are created by oysters growing upon each other in layers to create a hard surface over the
bottom. These reefs provide habitats and shelter for many other organisms such as
“gobies, blennies, toadfish and skilletfish.” More essential species such as the “white
perch, striped bass, blue crabs and diamondback terrapins, visit reefs to breed, find food
or seek refuge from predators.” The information on this web page also discusses how
oyster reefs benefit the oyster population by providing a place for oyster spat to grow,
and how they promote better water quality, a rise in the oyster population, and higher
biodiversity. The pictures used on our website come from this source.
Fahrenthold, David A. “Oyster Decision Could Alter Bay.” Washington Post 15 Feb.
2009, sec. C01. 17 Feb. 2009 <http://www.washingtonpost.com/wpdyn/content/article/2009/02/14/AR2009021401759.html?sid=ST200902140176
1>.
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This article is a very recent article from the Washington Post that is a general summary of
the issue at hand. It covers both sides of the argument. It recognizes the Chesapeake
Bay’s need for a restored oyster population for the ecosystem and for the people and
businesses that rely on oysters as a food source, but also identifies the risk that we can’t
take back the decision if the oysters are released freely.
"Gem of the ocean." The Economist [Cambridge, MD] 18 Dec. 2008. 18 Mar. 2009
<http://www.economist.com/world/unitedstates/displaystory.cfm?story_id=12
795573>.
This article from The Economist outlines several species of oysters, and the second half
of the article focuses mainly on Crassostrea virginica (the oyster in the Chesapeake Bay).
It talks about how oysters in the Chesapeake Bay have drastically declined since John
Smith first came to the area in 1608. The article also brings into focus the valuable niche
that oysters play in the ecosystem as a water filterer, and it touches on how the rising
human population in the Chesapeake Bay area contributed to the downfall of the oyster
population.
Harper, Scott. "Three methods vie to restore oysters to Chesapeake Bay." The
Virginian-Pilot 10 Nov. 2008. 20 Feb. 2009
<http://hamptonroads.com/2008/11/three-methods-vie-restore-oysterschesapeake-bay >.
This article revolves generally around the idea that we should focus more on restoring the
indigenous species of oyster in the Chesapeake Bay rather than introducing a nonnative
species and threatening the complete loss of the native species altogether. The author
includes that local governments have spent a relatively small amount of money on the
restoration of the eastern oyster, and that it is way too early to give up on the native species
yet by introducing an entirely new species.
Hrastar, Laura M. "Two If by Sea: Invasive Species Are Changing the Ocean
Environment." E May-June 2002: 18+. Questia. 13 Feb. 2009
<http://www.questiaschool.com/PM.qst?a=o&d=5000756387>.
This magazine article discusses the introduction of nonnative species into new bodies of
water in general; it does not focus specifically on the Chesapeake Bay, although it does
mention that Virginia released sterile oysters into the Bay against Maryland’s wishes.
This article provides valuable information about nonnative species and how they are both
accidentally and deliberately introduced into ecosystems. It also argues the repercussions
of these introductions, such as wiping out the native species.
Luckenbach, Mark. "Crassostrea ariakensis: Panacea or Pandora?" University of
Maryland Center for Environmental Science. Mar. 2004. Integration and
Application Network. 24 Feb. 2009 <http://www.ecocheck.org/communication/newsletters/publication/8/crassostrea_ariakensis_pan
acea_or_pandora_2004-03-01/>.
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This is an extremely valuable pamphlet made by the Integration and Application Network
of the University of Maryland Center for Environmental Science that assesses the potential
risks of introducing the Suminoe oyster into the Chesapeake Bay. It provides graphs and
charts of raw data comparing the growth of native and Suminoe oysters, and then presents
analyses and potential risks of such data.
"Oyster Wars: Oystering Methods." Chesapeake Bay Our History and Our Future.
2002. The Mariner's Museum. 14 May 2009
<http://www.mariner.org/chesapeakebay/oyster/mod007.html>.
This webpage was posted by the Mariner’s Museum, which is one of the largest nautical
museums in the world and located in Virginia, making the source very reliable and
educated. The information I found on this webpage included descriptions of two common
oyster harvesting methods, and discusses the effects of these methods on the ecosystem.
Also, it includes the conflicts that arose between the watermen who used these two
methods as they competed over territory off which each group could harvest.
Sagoff, Mark. "What's Wrong with Exotic Species?" University of Maryland. Web.
21 Feb. 2011.
<https://scholar.vt.edu/access/content/user/hullrb/PUBLIC/sagoffexoticspecies.
pdf>.
This pdf file was linked to our debate group’s website, posted by Professor Hull. This pdf
file addresses the arguments surrounding introducing foreign species. There are several
references to oysters, in other parts of the world and specifically in the Chesapeake Bay
too. One point very relevant to our argument is that even though the Asian oyster is more
resistant to diseases that plague the Chesapeake Bay, they are not any more capable of
handling pollution than the eastern oyster.
UMCES. "Resolving the Benefits and Risks of Crassostrea ariakensis." University of
Maryland Center for Environmental Science. 2002. 6 Mar. 2009 <
http://umces.edu/2002Session/Oyster_Position.pdf>.
This report analyzes the University of Maryland Center for Environmental Science’s
position on the introduction of the Pacific oyster, and outlines seven main points of their
overall opinion.
"2008 State of the Bay." Chesapeake Bay Foundation. 21 Feb. 2011
<http://www.cbf.org/Document.Doc?id=170>.
This is the 2008 edition of the annual “report card” for the Chesapeake Bay that assesses
certain thing such as the success of certain vital species like blue crabs and oysters. In the
2008 report, the oyster population received an F, with no change from the previous year.
It states that the native oysters are becoming more disease-resistant, and their life spans
are getting longer. It also states that there is an increase in funding for the reestablishment
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of this native species due to legislation in the Maryland and Virginia state legislatures.
This is a very credible source because it is compiled by the Chesapeake Bay Foundation,
whose sole purpose is to take the current conditions of the Bay and attempt to restore it to
a healthy environment.