Environmental Encyclopedia

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Environmental Encyclopedia 3

Mariculture

Smith, R. E. Ecology and Field Biology. 4th ed. New York: Harper &

Row, 1990.

ERIODICALS

Lugo, A. E., and S. C. Snedaker. “The Ecology of Mangroves.” Annual

Review of Ecology and Systematics 5 (1974): 39–64.

tzler, K., and C. Feller. “Mangrove Swamp Communities.” Oceanus 30

(1988): 16–24.

Manure

see

Animal waste

Manville Corporation

see

Asbestos

Marasmus

A severe deficiency of all nutrients, categorized along with

other protein energy malnutrition disorders. Marasmus,

which means “to waste” can occur at any age but is most

commonly found in neonates (children under one year old).

Starvation resulting from marasmus is a result of protein

and carbohydrate deficiencies. In developing countries and

impoverished populations, early weaning from breast feeding

and over dilution of commercial formulas places neonates

at high risk for getting marasmus.

Because of the deficiency in intake of all dietary nutri-

ents, metabolic processes--especially liver functions--are

preserved, while growth is severely retarded. Caloric intake

is too low to support metabolic activity such as protein

synthesis or storage of fat. If the condition is prolonged,

muscle tissue wasting will result. Fat wasting and

anemia

are

common and severe. Severe vitamin A deficiency commonly

results in blindness, although if caught early, this process

can be reversed. Death will occur in 40% of children left

untreated.

Mariculture

Mariculture is the cultivation and harvest of marine

flora

and

fauna

in a controlled saltwater

environment

. Sometimes

called marine fish farming, marine

aquaculture

, or aquatic

farming, mariculture involves some degree of human inter-

vention to enhance the quality and/or quantity of a marine

harvest. This may be achieved by feeding practices, protec-

tion from predators, breeding programs, or other means.

Fish, crustaceans, salt-water plants, and shellfish may

be farm raised for bait, fishmeal and fish oil production,

scientific research,

biotechnology

development, and repop-

ulating threatened or

endangered species

. Ornamental

867

fish are also sometimes raised by fish farms for commercial

sales. The most widespread use of aquaculture, however, is

the production of marine life for human food consumption.

With seafood consumption steadily rising and

overfishing

of the seas a growing global problem, mariculture has been

hailed as a low-cost, high-yield source of animal-derived

protein.

According to the Fisheries Department of the United

Nations’ Food and Agriculture Organization (FAO), over

33 million metric tons of fish and shellfish encompassing

220 different

species

are cultured (or farmed) worldwide,

representing an estimated $49 billion in 1999. Pound for

pound, China leads the world in aquaculture production

with 32.5% of world output. In comparison, the United

States is only responsible for 4.4% of global aquaculture

output by weight. Just 7% of the total U.S. aquatic produc-

tion (both farmed and captured resources) is attributable

to aquaculture (compared to 62% of China’s total aquatic

output).

In the United States, Atlantic

salmon

and channel

catfish represent the largest segments of aquaculture produc-

tion (34% and 40%, respectively, in 1997). Though most

farmed seafood is consumed domestically, the United States

imports over half of its total edible seafood annually, repre-

senting a $7 billion annual trade deficit in 2001. The Depart-

ment of Commerce launched an aquaculture expansion pro-

gram in 1999 with the goal of increasing domestic seafood

supply derived from aquaculture production to $5 billion

annually by the year 2025. According to the U.S. Joint

Subcommittee on Aquaculture, U.S. aquaculture interests

harvested 842 million pounds of product at an estimated

value of $987 million in 1999.

To encourage further growth of the U.S. aquaculture

industry, the National Aquaculture Act was passed in 1980

(with amendments in 1985 and 1996). The Act established

funding and mandated the development of a national aqua-

culture plan that would encourage “aquaculture activities

and programs in both the public and private sectors of the

economy; that will result in increased aquacultural produc-

tion, the coordination of domestic aquaculture efforts, the

conservation

and enhancement of aquatic resources, the

creation of new industries and job opportunities, and other

national benefits.”

In the United States, aquaculture is regulated by the

U.S. Department of Agriculture

(USDA) and the Depart-

ment of Commerce through the National Marine Fisheries

Service (NMFS),

National Oceanic and Atmospheric Ad-

ministration

(NOAA). State and local authorities may also

have some input into the location and practices of maricul-

ture facilities if they are located within an area governed by

a Coastal Zone Management Plan (CZMP). Coastal Zone

Management Plans, as authorized by the

Coastal Zone

Environmental Encyclopedia 3

Mariculture

Management Act

(CZMA) of 1972, allow individual states

to determine the appropriate use and development of their

respective coastal zones. Subsequent amendments to the

CZMA have also made provision for states to be eligible

for federal funding for the creation of state plans, procedures,

and regulations for mariculture activities in the coastal zone.

Tilapia, catfish, striped bass, yellow perch, walleye,

salmon, and trout are just a few of the fresh and salt-water

finned fish species farmed in the United States. Crawfish,

shrimp, and shellfish are also cultured in the U.S. Some

shellfish, such as oysters, mussels, and clams, are “planted”

as juveniles and farmed to maturity, when they are harvested

and sold. Shellfish farmers buy the juvenile shellfish (known

as “spat") from shellfish hatcheries and nurseries. Oysters

and mussels are attached to lines or nets and put in a con-

trolled ocean environment, while clams are buried in the

beach or in sandy substrate below low tide. All three of these

shellfish species feed on

plankton

from salt water.

But just as overfarming takes a toll on terrestrial

natu-

ral resources

, aquaculture without appropriate environ-

mental management can damage native ecosystems. Farmed

fish are raised in open-flow pens and nets. Because large

populations of farmed fish are often raised in confined areas,

disease spreads easily and rapidly among them. And farmed

fish often transmit sea lice and other

parasites

and diseases

to wild fish, wiping out or crippling native stock. Organic

pollution

from

effluent

, the waste products from farmed

fish, can build up and suffocate marine life on the sea floor

below farming pens. This waste includes fish feces, which

contributes to

nutrient loading

, and

chemicals

and drugs

used to keep the fish disease free and promote growth. It

also contains excess fish food, which often contains dyes to

make farmed fish flesh more aesthetically analogous to its

wild counterparts.

Farmed fish that escape from their pens interbreed

with wild fish and weaken the genetic line of the native

stock. If escaped fish are diseased, they can trigger outbreaks

among indigenous marine life. Infectious Salmon

Anemia

a viral disease that has plagued fish farms in New Brunswick

and Scotland in the 1990s, was eventually found in native

salmon. In 2001, the disease first appeared at U.S. Atlantic

salmon farms off the coast of Maine.

The use of drugs in farmed fish and shellfish intended

for human consumption is regulated by the U.S.

Food and

Drug Administration

(FDA). In recent years,

antibiotic

resistance

has been a growing issue in aquaculture, as fish

have been treated with a wide array of human and veterinary

antibiotic drugs to prevent disease.

The commercial development of genetically-engi-

neered, or transgenic, farmed fish is also regulated by FDA.

As of May 2002, no transgenic fish had been cleared by

FDA for human consumption. The impact transgenic fish

868

may have on the survival and reproduction of native species

will have to be closely followed if and when commercial

farming begins.

As mandated by the 1938 Mitchell Act, the NMFS

funds 25 salmon hatcheries in the Columbia River Basin of

the Pacific Northwest, the largest federal marine fishery

program in the United States. These aquaculture facilities

were originally introduced to assist in repopulation of salmon

stocks that had been lost to or severely hampered by hydro-

electric dam projects. However, some environmentalists

charge that the salmon hatcheries may actually be endanger-

ing wild salmon further, by competing for local

habitat

and

weakening the genetic line of native species.

Without careful resource management, aquaculture

may eventually take an irreversible toll on other non-farmed

marine species. Small pelagic fish, such as herring, anchovy,

and chub, are captured and processed into fish food com-

pounds for high-density carnivorous fish farms. According

to the FAO, at its current rate, fish farming is consuming

twice as many wild fish in feeding their domestic counter-

parts as aquaculture is producing in fish harvests—an average

of 1.9 kg of wild fish required for every kilogram of fish

farmed.

No matter how economically sound mariculture has

been, it has also led to serious habitat modification and

destruction, especially in mangrove forests. In the past

twenty years, the area of mangrove forests have dwindled

by 35% worldwide. Though some of that loss is due to active

herbicide

control of mangroves, their conversion to salt

flats, and the industrial harvesting of forest products (wood

chips and lumber), mariculture is responsible for 52% of the

world’s mangrove losses.

Mangrove forests are important to the environment

because these ecosystems are

buffer

zones between saltwater

areas and freshwater/land areas. Mangroves act as

filters

for

agricultural nutrients and pollutants,

trapping

these con-

taminants before they reach the deeper waters of the ocean.

They also prevent coastal

erosion

, provide spawning and

nursery areas for fish and shellfish, host a variety of migratory

wildlife

(birds, fish, and mammals), and support habitats

for a number of endangered species.

Shrimp farming, in particular, has played a major role

in mangrove forest reduction. Increasing from 3% to 30% in

less than 15 years, commercial shrimp farming has impacted

coastal mangroves profoundly by cutting down mangrove

trees to create shrimp and prawn ponds. In the Philippines,

50% of the mangrove environments were converted to ponds

and between 50% and 80% of those in Southeast Asia were

lost to pond culture as well.

Shrimp mariculture places high demands on resources.

It requires large supplies of juvenile shrimp, which can seri-

ously deplete natural shrimp stocks, and large quantities of

Environmental Encyclopedia 3

Marine ecology and biodiversity

shrimp meal to feed them. There also is considerable waste

derived from shrimp production. This can pump organic

matter and nutrients into the ponds, causing eutrophication,

which causes algae bloom and oxygen depletion in the ponds

themselves or even downstream. Many shrimp farmers need

to pump pesticides, fungicides, parasiticides, and algicides

into the ponds between harvests to sterilize them and miti-

gate the effects of nutrient loading. Shrimp ponds also have

extremely short life spans, usually about 5–10 years, forcing

their abandonment and the cutting of more mangrove forests

to create new ponds.

Mariculture also limits other marine activities along

coastal waters. Some aquaculture facilities can occupy large

expanses of ocean along beaches which become commercial

and recreational no-fish zones. These nursery areas are also

sensitive to disturbances by recreational activities like boating

or swimming and the introduction of pathogens by domestic

or farm animals.

[Paula Anne Ford-Martin]

ESOURCES

OOKS

Food and Agriculture Organization of the United Nations. The State of

World Fisheries and Aquaculture Rome, Italy: FAO, 2000. [cited June 5,

2002]. <http://www.fao.org/DOCREP/003/X8002E/X8002E00.htm>.

Jahncke, Michael L. et al.Public, Animal, and Environmental Aquaculture

Health Issues. New York: John Wiley & Sons, 2002.

Olin, Paul. “Current Status of Aquaculture in North America.” From

Aquaculture in the Third Millennium: Technical Proceedings of the Conference

on Aquaculture in the Third Millennium, Bangkok, Thailand. 20-25 February

2000.Rome, Italy: FAO, 2000.

ERIODICALS

Barcott, Bruce, and Natalie Fobes. “Aquaculture’s Troubled Harvest.”

Mother Jones 26, no.6 (November –December 2001): 38 (8).

Naylor, Rosamond, et al. “Effect of Aquaculture on World Fish Supplies.”-

Nature(June 29, 2000).

THER

“National Aquaculture Policy, Planning, and Development.” 16 USC 2801.

[cited June 4, 2002]. <http://www.access.gpo.gov/uscode/title16/

chapter48_.html>.

National Marine Fisheries Service, National Oceanic and Atmospheric

Administration. Aquaculture. [cited July 2002]. <http://www.nmfs.noaa.-

gov/aquaculture.htm>.

RGANIZATIONS

The Northeast Regional Aquaculture Center, University of Massachusetts

Dartmouth, Violette Building, Room 201 285 Old Westport Road,

Dartmouth, MA USA 02747-2300 (508) 999-8157, Fax: (508) 999-8590,

Toll Free: (866) 472-NRAC (6722), Email: nrac@umassd.edu, http://

www.umassd.edu/specialprograms/NRAC/

869

Marine ecology and biodiversity

Understanding the nature of ocean life and the patterns of

its diversity represents a difficult challenge. Not only are

there technical difficulties involved with studying life under

water (high pressure, need for oxygen tanks, lack of light),

there is an urgency to develop a greater understanding of

marine life as links between ocean processes and the larger

patterns of terrestrial life become more well known. Our

current understanding of oceanic life is based on three princi-

pal concepts: size, complexity, and spatial distribution.

Our knowledge about the size of the ocean’s domain is

grounded in three great discoveries of the past few centuries.

When Magellan first circumnavigated the earth he inadver-

tently found that the oceans were a continuous water body,

rather than a series of discrete bodies of water. Some time

later, the encompassing nature of the world oceans was fur-

ther clarified by the discovery that the oceans were a chemi-

cally uniform aqueous system. All of the principal ions (so-

dium, chloride, and sulfate) exist in the same concentrations.

The third discovery, still underway, is that the ocean is

composed of comparatively immense ecological systems.

Thus in most ways the oceans are a unified system which is

the first defining characteristic of the marine

environment

There is, however, a dichotomy between the integral

nature of the ocean and the external forces played upon it.

Mechanical, thermodynamic, chemical, and biological forces

create variation through such things as differential heating,

Coriolis force, wind, dissolved gases,

salinity

differences,

and evaporation. The actions in turn set controls in motion

which move toward physical equilibrium through feedback

mechanisms. Those physical changes then interact with bio-

logical systems in nonlinear ways, that is, out of synchroniza-

tion with the external stimuli and become quite difficult to

predict. Thus, we have the second broad characteristic of

the oceans, complexity.

The third major aspect of ocean life is that life itself

is sparse in terms of the overall volume of the oceans, but

locally productive systems can create immense populations

and/or sites with exceptionally high

species

diversity. Life

is arranged in active layers dictated by nutrients and light

in the horizontal planes, and by vertical current (downwelling

and upwelling) in the vertical planes. Life decreases through

the depth zones from the epipelagic zone in the initial 328

ft (100 m) of the water column to the bottom layers of water,

and then jumps again at the benthic layer at the water-

substrate interface. Life also decreases from the littoral zones

along the world’s shorelines to the open ocean, interrupted

by certain areas with special life supporting systems, like

floating sargasso weed beds.

In the past twenty years the focus of

conservation

has shifted to include not only individual species or habitats,

Environmental Encyclopedia 3

Marine Mammals Protection Act (1972)

but to a phenomenon called biological diversity, or

biodiver-

sity

for short. Biological diversity encompasses from three

to four levels. Genetic diversity is the level of genotypic

differences within all the individuals that constitute a popula-

tion of organisms; species diversity refers to the number of

species in an area; and community diversity to the number

of different community types in a landscape. The highest

level, landscape diversity has not frequently been applied in

aqueous environments and will not be discussed here.

Commonly, species diversity is interpreted as biologi-

cal diversity, and since few marine groups, except marine

mammals, have had very much genetic work done, and com-

munity functions are only well known from a few systems,

it is the taxonomic interpretation of diversity that is most

commonly discussed (e.g., species or higher taxonomic levels

such as families and classes, orders and phyla). Of all the

species that we know, roughly 16% are from the seas. General

diversity patterns in the sea are similar to those on land,

there are more smaller than larger species, and there are

more tropical species than temperate or polar species. There

are centers of diversity for specific taxa, and the structure of

communities and ecosystems is based on particular patterns

of energy availability. For example,

estuary

systems are

productive due to importation of

nitrogen

from the land,

coral reefs are also productive, but use scarce nutrients effi-

ciently by specially adapted filter feeding mechanisms. Abys-

sal communities, on the other hand, depend on their entire

energy supply from

detritus

fall from upper levels in the

ocean. Perhaps the most specifically adapted of all life forms

are the hydrothermal vent communities that employ

chemo-

synthesis

rather than

photosynthesis

for primary produc-

tion. Water temperature, salinity, and pressure create dif-

fering ecosystems in ways that are distinctly different from

terrestrial systems. In addition, the boundaries between sys-

tems may be dynamic, and are certainly more difficult to

detect than on land.

Most marine biodiversity occurs at higher taxonomic

levels, while the land holds more species, most of them are

arthropods. Most of the phyla (32 of 33) that we now know

are either marine, or both marine and non-marine, while

only one is exclusively non-marine. Thus most of the major

life plans exist in the sea.

We are now learning that the number of species in

the ocean is probably underestimated as we discover more

cryptic species, very similar organisms that are actually dis-

tinct, many of which have been discovered on the deep ocean

floor. This is one of the important diversity issues in the

marine environment. Originally, the depths were cast as

biological deserts, however, that view may have been pro-

moted by a lack of samples, the small size of many benthic

invertebrates, and the low density of benthic populations in

the deep sea beds.

870

Improved sampling since the 1960s changed that view

to one of the ocean floor as a highly species diverse environ-

ment. The deep sea is characterized by a few individuals in

each of many species; rarity dominates. Whereas, in shallow

water benthic environments, there are large, dense popula-

tions dominated by a few species. At least three theoretical

explanations for this pattern have been made. The stability-

time hypothesis suggests that ocean bottoms have been very

stable environments over long periods of time. This condi-

tion causes very finely tuned adaptations to narrow niches,

and results in many closely related species. The disturbance

or “cropper” hypothesis suggests that intense predation of

limited food sources prevents populations from reaching

high levels and because the food source is dominated by

detrital rain, generalist feeders abound and compete for the

same food, which results in only small differences between

species. A third hypothesis is that the area of the deep sea

bed is so large it supports many species, following from

generalizations made by the species area relationship concept

used in

island biogeography

theory. The picture of species

number and relative rarity is still not clearly understood.

In general, some aspects of marine biology are well

studied. Rocky intertidal life has been the subject of major

ecological research and yielded important theoretical ad-

vances. Similarly, coral reefs are the subject of many studies

of life history

adaptation

and evolutionary biology and

ecology

. Physiology and morphology research has used

many marine animals as examples of organisms’ functions

under extreme conditions. This new found knowledge is

timely. Up until now we have considered the oceans as an

inexhaustible source of food and a sink for our wastes, yet

we now realize they are neither. Relative to the land, the

sea is in good ecological condition, but to prevent major

ecological problems in the marine environment we need to

increase human knowledge rapidly and manage our behavior

toward the oceans very conservatively, which is a difficult

task under the conditions where the ocean is treated as a

common resource.

[David Duffus]

Marine Mammals Protection Act

(1972)

The Marine Mammals Protection Act (MMPA) was ini-

tially passed by Congress in 1972 and is the most compre-

hensive federal law aimed at the protection of marine mam-

mals. The MMPA prohibits the taking (i.e., harassing,

hunting

, capturing, or killing, or attempting to harass, hunt,

capture, or kill) on the high seas of any marine mammal by

persons or vessels subject to the jurisdiction of the United

States. It also prohibits the taking of marine mammals in

Environmental Encyclopedia 3

Marine Mammals Protection Act (1972)

An example of a marine ecosystem. (Illustration by Hans & Cassidy.)

waters or on land subject to United States jurisdiction and

the importation into the United States of marine mammals,

parts thereof, or products made from such animals. The

MMPA provides that civil and criminal penalties apply to

illegal

takings

The MMPA specifically charges the National Marine

Fisheries Service (NMFS) with responsibility for the protec-

tion and

conservation

of marine mammals. The NMFS is

given statutory authority to grant or deny permits to take

whales

dolphins

, and other mammals from the oceans.

The original legislation established “a moratorium on

the taking of marine mammals and marine mammal prod-

ucts...during which time no permit may be issued for the

taking of any marine mammal and no marine mammal may

be imported into the United States.” Four types of exceptions

allowed for limited numbers of marine mammals to be taken:

(1) animals taken for scientific review and public display,

after a specified review process; (2) marine mammals taken

incidentally to

commercial fishing

operations prior to Oc-

tober 21, 1974; (3) animals taken by Native Americans and

Inuit Eskimos for subsistence or for the production of tradi-

tional crafts or tools; and (4) animals taken under a temporary

871

exemption granted to persons who could demonstrate eco-

nomic hardship as a result of MMPA (this exemption was

to last for no more than a year and was to be eliminated in

1974). MMPA also sought specifically to reduce the number

of marine mammals killed in purse-seine or drift net opera-

tions by the commercial tuna industry.

The language used in the legislation is particularly

notable in that it makes clear that the MMPA is intended to

protect marine mammals and their supporting

ecosystem

rather than to maintain or increase commercial harvests:

“[T]he primary objective in management should be to main-

tain the health and

stability

of the marine ecosystem.

Whenever consistent with this primary objective, it should

be the goal to obtain an optimum sustainable population

keeping in mind the optimum

carrying capacity

of the

habitat.”

All regulations governing the taking of marine mam-

mals must take these considerations into account. Permits

require a full public hearing process with the opportunity

for judicial review for both the applicant and any person

opposed to the permit. No permits may be issued for the

taking or importation of a pregnant or nursing female, for

Environmental Encyclopedia 3

Marine pollution

taking in an inhumane manner, or for taking animals on

the

endangered species

list.

Subsidiary legislation and several court decisions have

modified, upheld, and extended the original MMPA: Globe

Fur Dyeing Corporation v. United States upheld the constitu-

tionality of the statutory prohibition of the killing of marine

mammals less than eight months of age or while still nursing.

In Committee for Humane Legislation v. Richardson,

the District of Columbia Court of Appeals ruled that the

NMFS had violated MMPA by permitting tuna fishermen

to use the purse-seine or drift net method for catching yel-

lowfin tuna, which resulted in the drowning of hundreds of

thousands of porpoises.

Under the influence of the Reagan Administration,

MMPA was amended in 1981 specifically to allow this type

of fishing, provided that the fishermen employed “the best

marine mammal safety techniques and equipment that are

economically and technologically practicable.” The Secretar-

ies of Commerce and the Interior were empowered to autho-

rize the taking of small numbers of marine mammals, pro-

vided that the

species

or population stocks of the animals

involved were not already depleted and that either Secretary

found that the total of such taking would have a negligible

impact.

The 1984 reauthorization of MMPA continued the

tuna industry’s general permit to kill incidentally up to

20,500 porpoises per year, but provided special protection

for two threatened species. The new legislation also required

that yellowfin tuna could only be imported from countries

that have rules at least as protective of porpoises as those of

the United States.

In Jones v. Gordon (1985), a federal district court in

Alaska ruled in effect that the

National Environmental

Policy Act

provided regulations which were applicable to the

MMPA permitting procedure. Significantly, this decision

made an

environmental impact statement

mandatory

prior to the granting of a permit.

Presumably owing to the educational, organizing, and

lobbying efforts of environmental groups and the resulting

public outcry, the MMPA was amended in 1988 to provide

a three-year suspension of the “incidental take” permits,

so that more ecologically responsible standards could be

developed. Subsequently, Congress decided to prohibit the

drift netting method as of the 1990 season.

In 1994, the MMPA was amended to include more

concrete definitions of harassment levels and grouped them

as level A harassment (potential to hurt a wild marine mam-

mal) and level B harassment (potential to disrupt their

envi-

ronment

or biology). The 1994 amendments also con-

structed new restrictions of photography permits and states

872

under harassment level B that scientific research must limit

its influence on the marine mammals being studied.

[Lawrence J. Biskowski]

ESOURCES

OOKS

Dolgin, E. L., and T. G. P. Guilbert, eds. Federal Environmental Law.

St. Paul, MN: West Publishing Co., 1974.

Freedman, W. Federal Statutes on Environmental Protection. New York:

Quorum Books, 1987.

ERIODICALS

Hofman, J. “The Marine Mammals Protection Act: A First of Its Kind

Anywhere.” Oceanus 32 (Spring 1989): 7–16.

THER

National Marine Fisheries Services. [cited June 2002]. <http://

www.nmfs.noaa.gov>.

Marine pollution

Marine

pollution

is a major threat to any organism living

in or depending upon the ocean. Human impact on coastal

and open ocean habitats comes in many forms:

nutrient

from agricultural

runoff

and sewage discharges,

toxic chemical inputs from industry and agriculture,

petro-

leum

spills, and inert solid wastes. While there has been

some recognition of the destruction of marine systems from

pollution, regulations are often weak or are not enforced.

Recent efforts have lead to slow recovery of some coastal

areas, but many of the detrimental practices continue and

some systems may never recover.

Nutrient loading is perhaps the most well-studied form

of pollution, and its biological consequences have been ob-

served and documented. Algal blooms, including red tides,

have been attributed to elevated nutrient levels in coastal

systems. These blooms, through their

respiration

and

de-

composition

, can deplete the levels of

dissolved oxygen

in the waters to almost zero, killing

zooplankton

, fish,

and shellfish. These nutrients often come from runoff of

agricultural fertilizers, the use of which has increased seven-

fold since 1950. It is estimated that approximately 25 percent

of the 46.8 million metric tons of

fertilizer

used in the

United States annually enters rivers and coastal waters.

Another source of nutrients is the

discharge

of sew-

age. The United States and England are the only countries

that dump

sludge

into the oceans, averaging 17 million

metric tons annually between them. Throughout the world,

however, raw sewage is released into rivers and coastal habi-

tats by many countries, leading to algal blooms and increased

biochemical oxygen demand

. BOD, the rate at which

oxygen disappears from a sample of water, increases dramati-

Environmental Encyclopedia 3

Marine pollution

cally with loading of organic material such as sewage, and

results in the lowering of dissolved oxygen levels. The wastes

of domesticated animals may also have a major impact in

some systems. A single cow produces approximately 31 lb

(14 kg) of waste per day, the equivalent of ten people. When

discharged into rivers or coastal waters, wastes produced by

large herds or

feedlots

may have substantial effects.

Boston Harbor is considered to be one of the most

polluted harbors in the United States. Since Europeans set-

tled in the Boston area, domestic wastes have been dis-

charged directly into the harbor. As Boston’s population

grew, so did the dumping, a problem exacerbated by the

growth of industry in the late nineteenth and early twentieth

centuries. Fish and shellfish in the harbor contain toxic

levels of polychlorinated biphenyl (PCB) and

heavy metals

BOD levels are astronomical, and dissolved oxygen levels

are low. In 1984, the Massachusetts

Water Resources

Au-

thority (MWRA) was formed and has managed to improve

water quality

of the harbor slightly. Recommendations of

the MWRA have been hard to enact, however.

Sewage

treatment

modifications have been met with

Environmen-

tal Protection Agency

(EPA) and State objections, shelving

the project while courts decide the fate of environmental

quality in Boston Harbor.

Toxic substances are introduced into the marine

envi-

ronment

from various sources, some of which may be hun-

dreds of kilometers away. Heavy metals, pesticides, and

acid

rain

threaten not only coastal and estuarine systems, but

also life in the open ocean. Heavy metals occur in many

forms, some of which are soluble in seawater. These soluble

compounds may not be the forms in which they were origi-

nally released into the environment, often making their

sources difficult to determine. Many heavy metals are re-

leased in industrial effluents, especially from chemical plants,

smelters, and mining runoff. These compounds may affect

humans directly through contact, or indirectly, from the

consumption of fish and shellfish, where metals often accu-

mulate in tissues.

Between the late 1930s and the mid-1950s, a Japanese

chemical company manufacturing acetaldehyde discharged

mercury

into Minamata Bay, where it formed a soluble

compound that accumulated in fish. It was not until 50

people died of

Minamata disease

and hundreds were left

with debilitating nervous disorders from eating poisoned fish

that environmental studies were initiated. Finally, in 1969,

the plant was closed. Other metals, such as zinc,

cadmium

copper

, and silver, are commonly discharged into marine

systems by industry. Not only are these metals toxic by

themselves, but synergistic effects compound their toxicity.

Acid

precipitation is rain, snow, or fog that has a lower

than normal and is caused by inputs of nitric and sulfuric

acid into the

atmosphere

from manufacturing and the

873

burning of

fossil fuels

, as in automobiles. These causes may

be far from the area of impact since prevailing winds can

carry pollutants considerable distances. The ocean has a high

buffer

capacity, that is, the ability to neutralize many of the

acid inputs. Therefore, most of the severe effects of acid rain

are observed in freshwater lakes and rivers. Some estuaries,

however, may also be seriously impacted, as has been ob-

served in the upper

Chesapeake Bay

. The pH of a river

feeding the Bay dropped from 6.3 to 5.8 between 1972 and

1978. Juvenile and spawning striped bass may not be able

to tolerate such high acidity. Precipitation of nitrogen-based

acid also increases nutrient loading in aquatic systems.

Toxic organic compounds, especially pesticides and a

family of

chemicals

known as PCBs, have been shown to

have serious effects on marine systems. Runoff has intro-

duced considerable amounts of PCBs, DDT, and many other

synthetic organic compounds into coastal areas. These com-

pounds may persist for many years. In 1976, Congress

banned the manufacture of PCBs, but they are still found

today as coolants in older transformers and buried in sedi-

ments. It is estimated that 1 percent of PCBs used have

reached the ocean. In 1987–1988, 700 bottlenose

dolphins

washed up on the U.S. Atlantic coast and some were found

to have elevated levels of PCBs and DDE (a form of DDT).

Biologists claim that these compounds inhibited the dol-

phins’ immune systems, making them vulnerable to infec-

tions. In 1975, workers at a chemical plant on the Chesa-

peake were poisoned when the insecticide

Kepone

was

leaked or dumped into the bay. The Kepone spread down-

stream where it poisoned fish and shellfish.

One of the most publicized sources of marine pollution

is that caused by petroleum products. While large

oil spills

can devastate a local area, equally important is the discharge

of crude oil while cleaning bilges and emptying tanks at sea.

Over the past decade, an average of approximately 32 million

gallons (120 million l) of oil have been spilled annually. The

Gulf of Mexico has recorded the most spills, while spills in

the Persian Gulf average 2 million gallons (7 million l)

per year. Since tanker ports and refineries are, by necessity,

located on the coast, these sensitive areas receive considerable

damage from the spills. The damage to marine life is stag-

gering. Seabirds are killed by the hundreds of thousands

annually, their oil-matted plumage making flight impossible

and exposing them to hypothermia. Oil-soaked fur of marine

mammals loses its water repellency, also leading to death by

hypothermia. Ingestion of oil by fishes, birds, and mammals

also may result in death.

Hundreds of tons of inert solid wastes are dumped

into the oceans from ships annually. Of these,

plastics

and

polystyrene

(styrofoam) are deadly to marine life. Often

floating for hundreds of miles and lasting for many years,

plastics are frequently mistaken for food by fishes, turtles,

Environmental Encyclopedia 3

Marine protected areas

and mammals, and proceed to either interfere with subse-

quent feeding or strangle the consumer. It has been estimated

that plastics and discarded fishing gear, such as monofila-

ment line and discarded nets, kill one million seabirds and

150,000 marine mammals each year.

Beginning with the Refuse Act of 1899 and the

Water

Pollution

Act of 1948, there have been efforts to remedy

the polluted oceans. Not until 1972, however, was legislation

drafted that was powerful enough, and sufficient monies

appropriated, to effect any change. With the Federal Water

Pollution Act, or

Clean Water Act

, improvement of water

quality in the United States began. By 1985, five of the goals

of the 1972 Act were reached, and since then, the Clean

Water Act has been rewritten to reflect increasing national

concerns.

Pollution of the world’s oceans had become so

pervasive that an international convention was convened

in 1973 to establish laws governing the discharge of all

wastes into the ocean. The International Convention for

the Prevention of Pollution from Ships (1978), commonly

known as MARPOL, and subsequent annexes to the

convention, covers all

garbage

discharged by ships at sea

beyond three miles from shore. While it is too soon

to tell, adherence to the MARPOL agreement should

significantly reduce the amount of solid wastes polluting

the world’s oceans.

Boston Harbor, the Chesapeake Bay, and the

Medi-

terranean Sea

are the most publicized examples of marine

pollution. However, the problem is widespread. Many

estuaries in Southeast Asia, many coastal areas in Japan,

and the waters off Rio de Janeiro are also areas where

historical and current use of the waters as dumping grounds

has left them in disastrous conditions. The Golden Horn

estuary around Istanbul, Turkey, has been declared dead,

containing no living organisms and posing a threat to

surrounding waters at the eastern end of the Mediterranean.

Since humans have been living along the coasts and

using the seas as waste dumping grounds for thousands of

years, these areas are the most heavily impacted. What makes

matters worse is that coastal waters are vital spawning and

nursery grounds for most of the commercially harvested fish

and shellfish in marine systems. Destruction of these areas

has significant nutritional and economic repercussions. Ex-

amples of the world-wide destruction of marine habitats due

to pollution are numerous, but, with increased international

efforts to limit inputs and rehabilitate damaged areas, im-

provements in the health of marine systems may be seen.

See also Bioaccumulation; Estuary; Food chain/web; Heavy

metals and heavy metal poisoning

[William G. Ambrose Jr. and Paul E. Renaud]

874

ESOURCES

OOKS

Clark, R. B. Marine Pollution. New York: Oxford University Press, 1989.

Nybakken, J. W. Marine Biology: An Ecological Approach. 2nd ed. New

York: Harper and Row, 1988.

ERIODICALS

Dolin, E. J. “Boston’s Murky Political Waters.” Environment 34 (1992):

6–33.

Marine protected areas

Marine protected areas (MPAs)are marine environments

that enjoy certain federal, state, local, or tribal regulation

and

conservation

management programs by virtue of their

unique ecosystems and/or cultural resources.

Known variously as marine reserves, marine sanctuar-

ies, and/or no- take areas, marine protected areas may include

national marine sanctuaries, marine features of national parks

and monuments, marine

wildlife

refuges, fishery reserves,

estuarine reserves, or state conservation areas and reserves.

They may be regulated as no-take areas, meaning that marine

resources and/or marine life cannot be removed from these

sanctuaries. Or, they may allow fishing and other commercial

or recreational activities within certain guidelines and limita-

tions. Management of an MPA is determined on a site-by-

site basis by one or more federal, state, territorial, local, and/

or tribal regulatory authorities.

Marine protected areas are not just a reaction to the

effects of industrialization. They have existed in some form

among traditional fishing cultures for centuries. Tabu or

kapu areas, controlled by clans or chiefs in Oceania, created

no-take zones. When westernization occurred, many of these

areas disappeared. In recent years, some of these tabu areas

have been revived.

Some countries created protected areas along their

coastlines through governmental decrees or legislation. The

Royal

National Park

in New South Wales,

Australia

,is

perhaps the oldest protected area in the world. Designated

in 1879, the park prohibits the use of explosives, net-fishing,

and the commercial harvesting of oysters. Certain areas re-

strict all

commercial fishing

. Other Australian reserves fol-

lowed. Today, another Australian MPA, the

Great Barrier

Reef

Marine Park, is considered one of the most successful

multiple-use MPAs in the world.

Other governments soon instituted marine protected

areas on their shores. New Zealand has led the world with

the establishment of 291 MPAs. Africa has established 92

reserves, and Europe is rapidly catching up, with MPAs

popping up in France, Spain, Greece, Albania, Bosnia, and

Croatia.

Environmental Encyclopedia 3

Marine protected areas

Though the United States has 9,3208 mi.(150,000

km) of coastline and had some initial legislation in place, it

waited until serious damage was occurring before developing

a viable plan to coordinate the nation’s MPA-related initia-

tives. Unfortunately, much of the focus of the US MPAs

will first be on remediaton of many of its fragile coastal

environments before concentrating on developing an inclu-

sive plan for its extensive coastline.

In May 2000, President Clinton signed Executive Or-

der 13158 on Marine Protected Areas, which was designed

to ensure the long-term security of critical ocean habitats,

marine life, and cultural resources through an integrated

national network of science-based MPA selection and man-

agement. The order designated the Department of Interior

and Department of Commerce as jointly responsible for the

MPA mission to “(a) strengthen the management, protec-

tion, and conservation of existing marine protected areas and

establish new or expanded MPAs; (b) develop a scientifically

based, comprehensive national system of MPAs representing

diverse U.S. marine ecosystems, and the Nation’s natural

and cultural resources; and (c) avoid causing harm to MPAs

through federally conducted, approved, or funded activities.”

Executive Order 13158 mandated the creation of a

national database of MPAs. This register of nationally-rec-

ognized MPAs would promote integrated conservation ef-

forts between federal, state, and local authorities and stake-

holders. Order 13158 defined an MPA as “any area of the

marine

environment

that has been reserved by federal, state,

territorial, tribal or local laws or regulations to provide lasting

protection for part or all of the natural and cultural resources

therein.” To further hone this relatively broad-based defini-

tion, the

National Oceanic and Atmospheric Administra-

tion

(NOAA) has established five criteria for inclusion in

the MPA inventory:

The site must have defined geographical boundaries and

must be in federal, U.S. territorial, state, or tribal marine

areas.

The site must be marine in

nature

, meaning that it in-

cludes ocean or coastal waters, including intertidal areas,

bays, and estuaries. It may also be a part of the

Great

Lakes

or their connecting waters, and can include land as

an integral component of the site.

Must be established as a reserved area by Federal, state,

territorial, local, or tribal law or regulation.

Must be lasting, as in a permanent and year-round pro-

tected area.

Must have existing laws or regulations that are designed

and applied to afford the site with increased protection for

part or all of the natural and cultural resources therein.

The MPA list had not yet been developed as of May 2002.

875

The establishment of a MPA list or inventory would

bring further clarity and regulatory integration to a legacy

of environmental legislation affecting ocean habitats that

began with the National Marine Sanctuaries Act (NMSA)

in 1972 (and its amendments and reauthorizations in 1980,

1984, 1988, 1992, 1996, and 2000). NMSA, Title III of

the

Marine Protection, Research and Sanctuaries Act

was signed by President Nixon on the 100-year anniversary

of the

National Park Service

. The Act set up the criteria

for national sanctuaries that today only include 13 marine

areas spanning approximately 18,000 mi

(28,967.4 km

As of May 2002, U.S. nationally- designated sanctuaries

include:

Channel Islands. Designated as a marine sanctuary in 1980,

the Channel Islands are located off the coast of Santa

Barbara, California. The unique

ecosystem

of the sanctu-

ary is home to giant kelp forests and 27

species

whales

and dolphins.

Cordell Bank. Cordell Bank is a submerged island on the

edge of the continental shelf off the coast of San Francisco.

The sanctuary, created in 1989, covers 526 mi

(846.5 km

)

that are home to a rich and diverse array of marine life.

Fagatele Bay. A tropical

coral reef

formed by a now-extinct

volcano

, Fagatele Bay is located off of Tutuila, an island

of American Somoa. The sanctuary was designated in 1986.

Florida Keys. The Florida Keys National Marine Sanctuary

encompasses 28,000 nautical mi

(51,856 km

) surrounding

the Florida Keys, and includes such unique features as coral

reefs and mangroves. It was established in 1990.

Flower Garden Banks. A series of three sites off the coasts

of Texas and Louisiana, Flower Garden Banks was estab-

lished in 1992 and 1996 as a national marine sanctuary

(two sites in 1992 and the third in 1996). The area’s unique

coral reefs and twin salt domes host an abundance of tropi-

cal marine life.

Gerry E. Studds-Stellwagen Bank National Marine Sanctu-

ary. This nutrient-rich expanse of Massachusetts Bay is

home to the endangered right and humpback whales. It

was designated in 1992.

Gray’s Reef. Given sanctuary status in 1981 by President

Carter, Gray’s Reef is a sandstone reef with a “live-bottom

habitat"—attached corals, sponges, and other invertebrates.

The sanctuary encompasses 17 mi

(27.4 km

) off the coast

of Georgia.

Gulf of the Farallones. The 1,255 mi

(2,019.7 km

) Gulf

of the Farallones National Marine Sanctuary was created

in 1981. Located 30 mi. (48 km) west of San Francisco

Bay’s Golden Gate Bridge, the Farallones sanctuary is

home to a variety of

seals

sea lions

, and seabirds.

Hawaiian Islands Humpback Whale. An estimated two-

thirds of the entire Pacific humpback whale population

Environmental Encyclopedia 3

Marine Protection, Research and Sanctuaries Act (1972)

return to the

Hawaiian Islands

in the winter to breed,

calve, and raise their young. The sanctuary was designated

in 1992 to protect this important

habitat

Monitor. The first of only two archaeological sites of the

13 U.S. marine sanctuaries, the Monitor National Marine

Sanctuary is the location of the sunken remains of the

U.S.S. Monitor, the first ironclad Civil War battleship.

The Monitor site was the first U.S. marine sanctuary,

designated in 1975 in the coastal waters off North Carolina.

Monterey Bay. Another California coastal sanctuary, Mon-

terey Bay is the largest of the marine sanctuaries at over

5,200 mi

(8,368.4 km

). It was established in 1992.

Olympic Coast. The Olympic Coast National Marine Sanc-

tuary was designated in 1994 and covers 3,300 mi

(5,310.7

off the Washington State coast and Olympic Pen-

ninsula. It is home to a rich and complex intertidal ecosys-

tem and a variety of seabirds and marine mammals.

Thunder Bay. Thunder Bay National Marine Sanctuary

and Underwater Preserve is the only designated sanctuary

located in the Great Lakes. The 448 mi

(721 km

) Lake

Huron location, a historical shipping alley, is the site of

at least 116 nineteenth and twentieth- century shipwrecks.

It became a national sanctuary in 2000.

As of May 2002, NOAA had begun the designation

process for a fourteenth national marine sanctuary, the Ha-

waiian Islands Coral Reef Ecosystem Reserve, home to an

estimated 7,000 marine species.

The NMSA calls for marine use management that

balances the public’s right for appropriate recreational and

commercial use of protected areas with habitat conservation

and ecosystem needs. Some areas may allow recreational use

with permits, or during specific times of the year. Others

may restrict certain uses completely. Because human use of

marine resources frequently conflicts with

biodiversity

and

conservation goals, this is a major challenge of the ongoing

management of marine protected areas.

[Paula Anne Ford-Martin]

ESOURCES

OOKS

Committee on the Evaluation, Design, and Monitoring of Marine Reserves

and Protected Areas in the United States, Ocean Studies Board, National

Research Council. Marine Protected Areas: Tools for Sustaining Ocean Ecosys-

tems.Washington, D.C.: National Academy Press, 2001.

ERIODICALS

“Presidential Documents. Executive Order 13158 of May 26, 2000.” Federal

THER

“National Marine Sanctuaries Act (NMSA) of 1972.” Code of Federal Regu-

lations 16 USC 1431 et seq.

876

U.S. Department of Commerce and U.S. Department of the Interior.

Marine Protected Areas of the United States. [cited June 2, 2002]. <http://

www.mpa.gov>.

RGANIZATIONS

National Marine Sanctuary System, National Ocean Service, National

Oceanic and Atmospheric Administration, 1305 East-West Highway,

11th Floor, Silver Spring, MD USA 20910 (301) 713-3125, Fax: (301)

713-0404, Email: nmscomments@noaa.gov, http://www.sanctuaries.

nos.noaa.gov/

Marine Protection, Research and

Sanctuaries Act (1972)

The Marine Protection, Research and Sanctuaries Act of

1972 (also known as the National Marine Sanctuaries Act)

is a comprehensive law designed to deal with ocean resources.

The law has three main sections: first, it regulates

ocean

dumping

; second, it authorizes

marine pollution

research;

third, it establishes the marine sanctuary program. These

sanctuaries can be established to protect areas of significant

conservation

, cultural, ecological, educational, esthetic, his-

torical, or recreational values. A fourth component to the

law, added in 1990, establishes regional marine research

programs.

The law established a permit process administered by

the

Environmental Protection Agency

(EPA) to regulate

all ocean dumping, with the exception of

dredging

materi-

als, which require a permit from the

Army Corps of Engi-

neers

. The act mandated that ocean dumping of sewage

sludge

and industrial waste end by 1981, but this deadline

was missed. The

Ocean Dumping Ban Act

of 1988 amended

the 1972 law, establishing a deadline of December 31, 1991,

for the end of ocean dumping of sewage sludge. A system

of escalating fees and fines was incorporated into the act to

help reach the deadline. The law also immediately prohibits

the dumping of

medical waste

in the ocean

The marine sanctuaries can be designated in coastal

waters or in the

Great Lakes

. Thus far, 13 National Marine

Sanctuaries have been designated: Channel Islands (off the

coast of California), Cordell Bank (California), Fagatele Bay

(American Samoa), Florida Keys (Florida), Flower Garden

Banks (Louisiana/Texas), Gray’s Reef (Georgia), Gulf of the

Farallones (California), Humpback Whale (Hawaii), Key

Largo (Florida), Looe Key (Florida), Monitor (North Caro-

lina), Monterey Bay (California), and Sellwagen Bank (Mas-

sachusetts). Numerous additional sites are being studied for

designation. The sanctuaries range in size from the 0.25 mi

(0.65 km

). Fagatele Bay to the 5,312 mi

(13,758 km

)at

Monterey Bay (larger than Connecticut).

Designation is usually made by the Secretary of Com-

merce, after consultation with other agencies and the affected