Encyclopedia of Global Resources part 49 pps

Fish and Wildlife Service FWS grew out of two agencies: the Bureau of Fisheries 1871 in the Department of Commerce and the Bureau of Biologi-cal Survey 1885 in the Department of Agricult

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Chaparral-Dominated Lands

The chaparral of temperate coastal climates, such as

that in Southern California, ignites easily and is likely

to burn from surface fires every ten to fifteen years In

fact, without fire, chaparral fields, which also support

manzanita, scrub oak, and coyote brush, become

choked, and many nonsprouting shrubs die Light

fires every twenty to thirty years are therefore

neces-sary to species survival Unburned for longer than

that, the fields accumulate so much dead debris that

the chances for a tremendously destructive fire soar

Forest Fires

Great diversity in tree types and, accordingly, fire

fre-quency and intensity, exists among evergreen and

de-ciduous forests Forests can fall prey to all types of fire;

crown and high-intensity spotting fires are most

com-mon in Douglas fir-dominated areas, while mature

stands of pure juniper are nearly impossible to burn

In general, fire helps maintain the dominance of

pines by preventing hardwoods, which burn more

readily (with the exception of some oak species), from

invading Several pine and spruce species, most

nota-bly ponderosa pine, require fire-cleared soil to

germi-nate seeds Wildfire intervals range from five to ten

years for ponderosa pines and up to five hundred

years for redwoods

Beginning in the 1960’s, government land

manag-ers used controlled burns and unopposed wildfires to

clear away underbrush and dead trees in public

for-ests However, since such fires destroy public timber

resources and sometimes, out of control, ravage

pri-vate lands and human residential areas, the practice

has been controversial, especially after the

devastat-ing Yellowstone National Park fire of 1988

The political as well as economic infeasibility of

con-trolling overgrowth may have contributed to

South-ern California’s “Station Fire” of 2009, which ravaged

roughly two hundred square miles of the Angeles

Na-tional Forest and adjacent residential interface areas

(an area the size of San Francisco) during the largest

forest fire in the history of Los Angeles County The

region, normally prone to fires driven by Santa Ana

winds, instead underwent a fuel-driven fire that

threat-ened lives and destroyed approximately one hundred

homes as well as vast areas of wildlife habitat Australia

experienced similar massive fires during this period

Such events, while part of a natural cycle, pose

im-mediate threats not only to ecological and other

natu-ral resources but also to human infrastructure when

development has encroached on the areas subject to burning Combined with evidence of global warming and concomitant trends toward droughts and longer

or unbroken “fire seasons,” such fires can be expected

to increase the strain on economic and human re-sources

Roger Smith

Further Reading

Carle, David Introduction to Fire in California Berkeley:

University of California Press, 2008

DeBano, Leonard F., Daniel G Neary, and Peter F

Ffolliott Fire’s Effects on Ecosystems New York:

J Wiley, 1998

Pyne, Stephen J Awful Splendour: A Fire History of Can-ada Vancouver: University of British Columbia Press,

2007

_ Fire in America: A Cultural History of Wildland and Rural Fire 1982 Reprint Princeton, N.J.:

Princeton University Press, 1988

_ World Fire: The Culture of Fire on Earth New

York: Holt, 1995

Quintiere, James G Fundamentals of Fire Phenomena.

Chichester, England: John Wiley, 2006

Rossotti, Hazel Fire New York: Oxford University

Press, 1993

Wein, Ross W., and David A MacLean, eds The Role of Fire in Northern Circumpolar Ecosystems New York:

Published on behalf of the Scientific Committee

on Problems of the Environment of the Interna-tional Council of Scientific Unions by Wiley, 1983

Whelan, Robert J The Ecology of Fire New York:

Cam-bridge University Press, 1995

Wright, Henry A., and Arthur W Bailey Fire Ecology: United States and Southern Canada New York: Wiley,

1982

Web Sites Canadian Forest Service, Natural Resources Canada

Canadian Wildland Fire Information System http://cwfis.cfs.nrcan.gc.ca/en_CA/index U.S Geological Survey

Natural Hazards: Wildfires http://www.usgs.gov/hazards/wildfires See also: Erosion and erosion control; Forest fires; Forest management; Forestry; Grasslands; Range-land; Slash-and-burn agriculture

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Fish and Wildlife Service, U.S.

Category: Government and resources

Date: Established 1940

The U.S Fish and Wildlife Service, a part of the U.S.

Department of the Interior, is the primary federal

agency charged with protecting the nation’s fish,

wild-life, and associated habitats.

Background

The U.S Fish and Wildlife Service (FWS) grew out of

two agencies: the Bureau of Fisheries (1871) in the

Department of Commerce and the Bureau of

Biologi-cal Survey (1885) in the Department of Agriculture

Each held specific duties designed to protect the

country’s fishing, game hunting, and other natural

re-sources Under Presidential Reorganization Plan 111,

Franklin D Roosevelt consolidated the agencies and

created the FWS in 1940

Impact on Resource Use

Under the Fish and Wildlife Act of 1956, the Fish and

Wildlife Service was given legislative status and

di-vided into two divisions: the Bureau of Commercial

Fisheries and the Bureau of Sport Fisheries and

Wild-life The latter eventually took over the agency when

the commercial division moved into the Department

of Commerce in 1970 The FWS is a bureau of the

De-partment of the Interior It seeks to enforce

legisla-tion pertaining to wildlife and to protect associated

natural resources A director, under the umbrella of

the secretary of the interior, is in charge of the nearly

nine thousand employees of the FWS

To fulfill its duties, the FWS developed a

three-pronged approach: conservation, research, and

en-forcement Conservation relates to the 38 million

hectares in more than seven hundred areas of the

Na-tional Wildlife Refuge System that fall under FWS

ju-risdiction In addition, the FWS maintains the

Na-tional Fish Hatcheries System and provides support

to state and local agencies seeking federal funding

or intervention Its research activities involve a

na-tional network of field agents and biologists who work

to protect wildlife and its surroundings FWS policy

maintains that the protection of habitat through

con-servation and research is essential to the survival of

animals Its mission includes particular attention to

endangered species

The agency’s approach to enforcement has evolved through the years In addition to its central adminis-trative office it has eight regional offices and almost seven hundred field offices Through its regional of-fices and hundreds of field stations, the FWS has in-creased the numbers of animal species under its care From regulating migratory bird hunting and issuing duck-hunting licenses to setting limits on fish catches and enforcing the protection of threatened wildlife, the FWS has greatly expanded its role over its history Eventually “wildlife” came to represent a traditional definition of animal life as well as fresh and anadro-mous fish, certain marine mammals, and identified endangered species In the late twentieth century,

as national policy extended to include a more conser-vational and environmental approach, the FWS re-sponded with improved regulation of wetlands and the wildlife refuge system Legislative support brought increased research into the water, air, and plant life of wildlife habitats In addition to preservation, one of the most important tasks of the FWS is education in wildlife and conservation, particularly geared to the youth of the United States The FWS features numer-ous programs addressing issues of wildlife The FWS has a law enforcement division aiming to stop crimes against wildlife and those committed on its lands The FWS also has the world’s only forensics laboratory devoted to solving and preventing crimes against wild-life

The 38-million-hectare National Wildlife Refuge System is the only collection of federal lands managed exclusively for the benefit of wildlife This beautiful ecosystem includes diverse water, land, and forest habitats About 750,000 hectares of wetlands, essen-tial to the health and welfare of wildlife and humans, are included in this total More than thirty-nine mil-lion tourists visit the National Wildlife Refuge System annually Despite the importance of this system, the FWS managed these habitats for decades without

an organic law “Organic law” means a fundamental constitution or law that outlines the basic principles

of government Without an organic law, the FWS over-saw the National Wildlife Refuge System by means

of piecemeal legislation and regulation Congress passed numerous important pieces of legislation af-fecting FWS throughout the second half of the twenti-eth century For example, the Federal Aid in Sport Fish Restoration Act (Dingell-Johnson Act), enacted

in 1950, established a program to improve the fishery resources of the nation The National Wildlife Refuge

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System Administration Act, enacted in 1966, served to

protect the refuge areas from damaging uses The

En-dangered Species Act, enacted in 1973, entrusted

FWS with responsibility over many endangered

spe-cies The Alaska National Interest Lands

Conserva-tion Act, enacted in 1980, greatly expanded the

Na-tional Wildlife Refuge System, adding more than 21

million hectares of land

A watershed moment for the FWS came in 1997

with the passage of perhaps the most important

legis-lation in its history The National Wildlife Refuge

Sys-tem Improvement Act of 1997 was a major legislative

scheme affecting federal use and oversight of wildlife

lands Congress passed the act as Public Law 105-57

President Bill Clinton signed the act on October 9,

1997 The National Wildlife Refuge System

Improve-ment Act provided the organic law for the FWS In

other words, all of the actions of the FWS should

fol-low from this act It represents a comprehensive set of

legislation that mandates the responsibilities and

ac-tions of the FWS as it relates to the National Wildlife

Refuge System The act is divided into ten parts,

cover-ing such topics as huntcover-ing, trappcover-ing, and fishcover-ing;

con-cerns relating to live wildlife and fish; the sale,

pur-chase, and transport of wild animals; and licensing,

enforcement, penalties, and regulations Perhaps most

important, the act gave a strong mission statement to

guide the Department of the Interior and the FWS

This mission statement emphasizes the mandate to

protect wildlife and maintain the diversity, health,

and outstanding qualities of the habitats The act

re-quired a new process to determine which recreational

activities are appropriate in the refuges The act also

recognized that traditional activities such as fishing,

hunting, and wildlife observation are appropriate

public uses of the National Wildlife Refuge System, as

long as they do not harm the environment Finally,

the National Wildlife Refuge System Improvement

Act required the FWS to devise a comprehensive plan

to conserve all of the refuges under its management

The FWS received $280 million under the

Ameri-can Recovery and Reinvestment Act of 2009 to

com-plete projects that enhance the wildlife habitats while

providing jobs and stimulating the economy This

measure harked back to the days of the Civilian

Con-servation Corps (CCC) The CCC (1933-1942) was

created as a project of the New Deal, both to provide

jobs in a time of economic crisis and to develop and

conserve natural resources in the United States In

late 2009, the FWS released a strategic plan to help the

wildlife and habitats under its management to survive the impact of global climate change

In its efforts to conserve, research, and protect through enforcement, the FWS often faces opposi-tion from business interests and conservaopposi-tion groups The logging industry, for example, has criticized cer-tain protective measures, claiming that they place more importance on animals than humans Conser-vation groups, on the other hand, have criticized the FWS for allowing controlled predatory animal reduc-tions on federal refuge land In all such instances, the FWS finds itself faced with balancing national policy with wildlife interests

The FWS provides a vital link between the U.S gov-ernment, U.S citizens, and the natural world The FWS prides itself on managing the largest and most impressive wildlife habitat in the world Through its protective as well as investigative functions, the FWS works to maintain a strong level of biodiversity in the United States

Jennifer Davis, updated by Howard Bromberg

Further Reading

Bean, Michael The Evolution of National Wildlife Law.

3d ed Westport, Conn.: Praeger, 1997

Fischman, Robert The National Wildlife Refuges: Coordi-nating A Conservation System Through Law

Washing-ton, D.C.: Island Press, 2003

Freyfogle, Eric, and Dale Goble Wildlife Law: A Primer.

Washington, D.C.: Island Press, 2009

See also: Conservation; Department of the Interior, U.S.; Endangered species; Endangered Species Act; Fisheries; Wetlands; Wildlife

Fisheries

Categories: Plant and animal resources;

environment, conservation, and resource management

Fisheries, places where fish or other aquatic foods are caught or taken, provide an important source of pro-tein Fishing technologies range in scope from simple hook-and-line fishing in small ponds to industrial op-erations that use huge nets stretching behind seagoing trawlers Many experts believe overfishing has placed fisheries throughout the world in danger of ecosystem collapse.

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Oceans cover nearly 71 percent of the Earth and

con-tain 86.5 percent of the Earth’s water (510 million

cu-bic kilometers) Freshwater areas cover an additional

1 percent of the Earth Most life exists in ecosystems at

or below the surface of water Aquatic ecosystems have

a distinct advantage over land-based ecosystems

be-cause their life-forms are not limited by a lack of water

Nutrient-rich areas of the ocean are green with lush

plant growth, and can produce more food than

culti-vated farmland Even polar ocean areas with pack

ice most of the year are rich with algae growing in

open areas and inside ice Furthermore, “blue-water

deserts”—ocean regions with low nutrient levels—

produce more biomass (total weight of plants and

ani-mals) per unit of surface than land deserts

Food resources from water include finned fish,

shellfish, crustaceans (such as shrimp, krill, and

lob-ster), cephalopods, some marine mammals and

rep-tiles, and plants Water plants should be included in a

discussion of fisheries because they are the ultimate

source of food for animals that are fished and because

some mixture of plants and animals are often

har-vested World fisheries and aquaculture supply more

than 145 million metric tons of high-protein food

each year, which is more than beef, pork, or poultry

Globally, fishing is a $92-billion-a-year industry

di-rectly employing nearly 38 million people and

indi-rectly employing an additional 162 million people

(Subsistence fishers in tropical areas are probably

undercounted in numbers but estimates suggest about

nineteen million fishers; financial measures are hard

to apply.) In the United States, commercial fishing

annually harvests roughly 3.65 billion kilograms of

fish and shellfish worth more than $4 billion In the

United States alone, the secondary market and

con-sumption value of seafood have an annual value of

more than $195 billion

Oceanic Plant Life

Sunlight drives photosynthesis, by which plants

sup-ply almost all food on Earth, either directly or

indi-rectly, through the animal life feeding on them

Be-cause the top several hundred meters of ocean water

absorb virtually all sunlight hitting it, these

upper-most waters contain the oceans’ supporting

photo-synthetic plants Below the oceans’ illuminated zone,

animal life becomes progressively scarcer, and

ani-mals feed on living and dead matter drifting down to

them

Biologically productive areas of oceans occur mostly

in coastal regions, where minerals and nutrients are washed from land and where currents and winds dredge nutrient-rich sediments from the near-shore ocean floor Similarly, nutrients from the deep ocean can be brought to coastal regions by differing ocean temperatures meeting to form convergent zones, re-sulting in upwelling—warm water rising to the surface and bringing with it conditions favorable for plant and animal life Less than 1 percent of ocean areas are occupied by coastal ecosystems, yet these areas are twenty times more productive than the open ocean Near-shore waters are home to mangrove swamps, salt marshes and tidal wetlands, coral reefs, and estuaries Between 95 and 98 percent of commercial fishery spe-cies spend their early lives in fertile estuary ecosys-tems Coral reefs harbor more plant and animal phyla than any other ecosystem; and tidal wetlands are the rearing grounds for vast numbers of crustaceans and mollusks These neshore waters are the primary ar-eas for marine life, and three-quarters of the world’s fish harvest occurs within 9 kilometers of continental shorelines

A number of freshwater and near-shore plants are similar to land plants, including species such as eel-grass, turtle eel-grass, and kelp, beds of which are often called ocean forests Many near-shore plants, such as nori in Japan, are eaten directly Others are harvested for use as food additives For instance, giant kelp (or bull kelp) off the west coast of North America is har-vested by clipping barges (which could be described

as floating lawnmowers) for agar and alginate, used for stabilizing ice cream and beer foam

Semiaquatic plants such as mangrove trees, cat-tails, and other swamp plants also have a tremendous effect on fisheries Many fish spawn and spend their early lives around these types of plants The areas where they are found are sometimes considered waste-land, but they are actually crucial to many fished spe-cies, including shrimp In fact, river estuaries, man-grove swamps, and salt marshes produce more organic material per unit area than any other areas on Earth Away from shallow water, most oceanic plants are drifting algae barely large enough to be seen without magnification In freshwater and near-shore waters, algae may comprise a large or small part of the ecosys-tem In the deep ocean, phytoplankton (from the Greek words for “plant” and “wanderer”) is one of the only food supplies for many marine animals Al-though individually small, phytoplankton numbers

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are so great that they represent most of the vegetable

mass in the oceans: an estimated new growth of 18

bil-lion metric tons per year Phytoplankton eaten by

tiny animals, such as zooplankton, are food for small

schooling fish, such as sardines, pilchard, herring,

capelin, and anchovy In turn, these fish are eaten by

higher predators in the food chain, such as cod and

mackerel, which are eaten by “top predators,” such as

tuna, sharks, and porpoises In each stage from

phyto-plankton to top predators, about 90 percent of the

food content is lost

Fishery Locations

The richest fisheries have traditionally been along

continental shelves Continental shelves are gently

sloping regions transitioning between the continents

and the deep ocean Continental shelves represent

only 8 percent of the ocean expanse Roughly 16

per-cent of the ocean expanse is continental slopes with

gradients about ten times steeper than the gently

slop-ing shelves Continental slopes drop off 500 to 3,000

meters into the ocean depths Along these

continen-tal slopes, nutrient-rich upwelling occurs Where the

continental shelves are broad, major fisheries exist—

or did exist before they were damaged by human

ac-tivities Three-quarters of all marine organisms spend

at least a portion of their lives along a continental

shelf

Major shelf fisheries include the waters around

Ice-land, the Patagonian shelf (extending to the Falkland

Islands), the Sea of Okhotsk, the shelf around Alaska,

island chains and coastal waters from Indonesia

through Japan, the Persian Gulf, and the Grand Banks

east of North America Major shelf fisheries that were

important but have declined because of overfishing

and pollution include the North Sea, the Baltic Sea,

the Black Sea, Chesapeake Bay, and many areas in the

Mediterranean

Coral reefs, which have some similarities to land

ecosystems, are actually colonies of tiny animals that

contain algae within their bodies Reefs are areas of

high productivity The algae provide oxygen and food

to the coral, while waste matter and carbon dioxide

from the coral are nutrients to the algae This

symbio-sis allows reef ecosystems to be as productive as

near-shore waters, even though nutrient levels are typically

lower for reefs in tropical waters However, this

symbi-osis also makes reefs vulnerable to excessive

fertiliza-tion from pollutants, particularly phosphates from

fertilizers and detergents Reefs are also highly

sensi-tive to changes in turbidity, saline variation, and water temperature

Corals actually rebuild their environment to sur-vive, and, in the process, create a more productive fishery Like shellfish, corals grow their own calcium-carbonate living environment, in which living layers build atop the remains of older generations The coral reefs grow with many gaps and fissures, allowing water to flow continually to the live corals These gaps provide hiding places and nests for many small and juvenile creatures, many of which help defend the corals from predators Because of corals, the islands of Polynesia have many small but rich fisheries The Great Barrier Reef on the north side of Australia is enriched by corals and has the added advantage of

a broad shelf area

Other natural areas of high productivity are cre-ated where deep water rises to the surface in an upwelling Exceptionally cold meltwater from Antarc-tica is heavier than the bottom water, so bottom water

is pushed toward the surface Consequently, one of the largest areas of high biomass is along the conti-nental slopes of the Antarctic

Another area of upwelling exists west of Peru, where a current from the north meets a current from the south, and the combined current flows west The resulting gap is filled by an upwelling that supports anchovy production Periodically, an increase in warmer water (the El Niño current) weakens this upwelling, causing a drastic fall in plankton, and hence anchovy, production A “crash” of this fishery

in the early 1970’s, a result of an El Niño, was made worse by overfishing Similar current-induced up-welling occurs along the Moroccan and Namibian coasts Waters off Alaska have upwelling and large shelf areas, making them especially fertile

Most of the deep ocean away from land is abyssal plain or “blue-water desert” with low productivity; this

is especially true near the equator These waters have sufficient nitrates and phosphates to support higher levels of marine life but lack trace amounts of iron, a mineral vital for phytoplankton survival

Existing Fisheries The evolution of fisheries has involved both the avail-ability of fish and the public’s taste in seafood Top predators, such as tuna, are prized for their taste, but schooling fishes that feed on zooplankton are har-vested in the greatest tonnage Another factor in the evolution of fisheries is that species tend to decline as

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they are overfished, so new species must be fished.

The schooling fish that generally represent the

high-est tonnage of fish caught are a cheap source of

pro-tein As such, roughly 25 percent of the fin catch

is processed into fishmeal for livestock, and an

addi-tional 50 percent of fishmeal is consumed by

aqua-culture Also, 70 percent of all fish oil is consumed by

aquaculture Invertebrates are much lower in

ton-nage than finned fish, but they make up a significant

percentage of the value of the fisheries trade They

include prized crustacean species such as lobster, king

crab, and shrimp They also include shellfish such as

clams, abalone, and scallops

Krill are small zooplankton crustaceans similar to

shrimp Krill are the primary food for baleen whales,

which strain water for their tiny prey Some limited

krill fishing has been done to provide fishmeal (It has

been noted that people may be slow to accept krill in

their diets on a significant scale because cooked krill

look similar to maggots.) The largest krill population

is in waters around Antarctica, where the krill

popula-tion is estimated at 600 million metric tons Further

estimations indicate that a sustainable yield for krill

would be one-tenth of this total These same Antarctic

waters also support a large population of whales,

which survive on krill Any overharvesting of krill

would have an adverse effect on whales The northern

polar region has the largest single-species fishery in

the world—pollock, which thrive in the Bering Sea

near Alaska The world’s largest remaining cod

fish-ery is in the Barents Sea of northern Europe The

Barents Sea fishery is threatened by pollution,

min-eral exploration, busy shipping lanes, overfishing,

and illegal fishing Unsustainable commercial fishing

practices, in combination with an illegal catch

esti-mated at 90 million metric tons per year, are pushing

the Barents Sea cod fishery toward collapse

Fishing Technologies

Fishing can be done with hooks, traps, or nets; all

three of these fishing methods are used by subsistence

fishers and small fishing operations For large-scale,

industrial fishing operations, nets are the most

practi-cal and efficient tools Large fishing operations

radi-cally changed fishing and the world’s fisheries in the

twentieth century

Although some mechanized fishing was done in

the nineteenth century, commercial fishing

produc-tion was only around 2.5 million metric tons at the

be-ginning of the twentieth century and had reached 18

million metric tons at the beginning of the 1950’s Then a combination of insecticides, newly introduced medicines, and better hygiene reduced disease, allow-ing a rapid growth in human population, which cre-ated a growing market for food At the same time, better transportation allowed rapid shipment of pre-mium catches, so lobsters, for instance, would never again be considered food for poor people along the coast The greater fish market was met by investments

in technology First came large boats, followed by so-nar navigation equipment, spotter aircraft, and nylon nets, which are nearly invisible to fish and are more re-sistant to rotting than natural fibers More important, large factory ships allow processing of the catch at sea

A factory ship need not steam back to port frequently, but can stay out fishing until its hold is full Factory ships also allow profitable fishing farther from shore, which is important because these ships often deplete nearby fisheries In one hour a factory ship can har-vest as much fish as a sixteenth century fishing boat took in a season

There are three major categories of nets: trawl nets, purse seines, and drift nets Trawl nets are coni-cal nets dragged across the bottom with the big, open-end first, funneling fish into the closed point of the cone Purse seines are nets held as vertical walls by floats at the top and weights at the bottom until the wall can surround an area of the water and the bottom can be pulled together In the 1970’s and 1980’s, com-mercial fishing fleets began using large drift nets, many as long as 50 kilometers These massive nets

“vacuumed” or “swept” vast swaths of ocean, collect-ing everythcollect-ing in their range Though the nets were intended for cod, tuna, and squid harvest, their use resulted in massive “bycatches” of nontarget species, including sharks, dolphins, whales, and sea turtles Such large drift nets were banned for use outside a na-tion’s 370-kilometer exclusive economic zone (EEZ), within which a country has exclusive control of all ma-rine resources Forty percent of the world’s oceans are under control of individual nations claiming EEZs, but nets as large as 2 kilometers are still in use on the open ocean

Large, high-tech operations (plus smaller but nev-ertheless highly capitalized operations) directly em-ploy more than one million people worldwide and take about two-thirds of the world’s harvest Some nineteen million subsistence fishers and small opera-tions take the balance The small operators are often poor, but they spend much less per unit catch and use

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most of what they catch This contrasts with industrial

fishing operations, which tend to specialize in a single

species As a result there are often “unwanted” catches

referred to as “bycatch.” Bycatch can be fish that are

too young, nontarget species, or over-quota However,

bycatch fish are usually dead from being netted and

dropped in a hold, sitting for minutes or hours during

the sorting process The bycatch is discarded back

into the sea and equates to more than 20 million

met-ric tons per year This dead and dumped bycatch

af-fects fish populations present and future

The Death of Traditional Fishing

By the early twenty-first century, fishing had become a

troubled industry, its many successes having led to a

string of related fishery collapses The basic problem

with fishing as it evolved in the latter twentieth

cen-tury was that it was a hunter-gatherer operation rather than an agricultural one: Fishers do not nurture and protect schools of fish as farmers protect herds of cat-tle This fact alone limits productivity For instance, there is little investment in habitat for fish, such as in maintaining wetlands for juveniles of many species or clear rivers and estuaries for salmon and other river-spawning fish

Worse, fisheries management according to the hunter-gatherer dynamic is based on the idea that the fish are common property, with each fishing opera-tion competing with the others for the fish Any fish-ers who hold back in catching fish to save breeding stock for the future lose catch to other fishers willing

to take the fish In 1976, Garrett Hardin applied the term “the tragedy of the commons” to the problem of overfishing The term has also been applied to the

Data from U.S National Oceanic and Atmospheric Administration, National Marine Fisheries Service,

, 2007.

States

7.4

1.7

5.7

2004 2003

2002 2001

2000 1995

1990

0

2

4

6

8

10

7.5

1.3

6.2

7.9

1.2

6.7

8.2

1.3

6.9

8.7

1.4

7.3

9.0

1.2

7.8

9.3

1.3

8.0

9.3

1.1

8.2

9.5

1.1 8.4

Human food Industrial use Total

U.S Domestic Fisheries Catch Totals

(billions of kilograms, live weight)

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grazing of cattle; however, cattle can at least be

counted, but fish populations are more likely to be

gauged by catch Thus, fishers using advanced

equip-ment to catch the dwindling numbers of fish can

cre-ate the illusion of a stable population An entire fish

species may ultimately be fished to near extinction,

and the fishery may collapse, but the worst offenders

will be the most profitable until the disaster occurs

Furthermore, many fishing practices have dire

ef-fects on other species More powerful boats and trawl

nets equipped with “rock-hoppers” and better

con-trols can drag rough-bottom areas with less danger

of snagging the nets Trawlers can work rough areas

that fishers have avoided before and can fish steadily

deeper-hunting bottom fish (such as cod, flounder,

eels, and turbot) However, the sea bottom is also

hab-itat for the young of many species and has food for

many others In a manner similar to coral reefs, the

bottom ecosystem functions best when old shells,

worm tunnels, and sponges and other attached

or-ganisms provide a complex environment where

juve-nile animals can hide from predators A

one-metric-ton boom dragging across the bottom kills attached

animals, compacts the sediment so that worms cannot

burrow well, silts some animals to death, and

gener-ally grinds the area down to wasteland Years later, the

lost production on the bottom manifests itself as

miss-ing adults elsewhere

Finally, the areas closest to land, which are usually

the richest fisheries, are subject to poisoning by

pol-lutants The Chesapeake Bay produces only a fraction

of the life that early settlers found there The Black

Sea, naturally darkened by anaerobic decomposition

(rotting without oxygen), is blacker because of

fertil-izer runoff and toxic contaminants In 1991, three

thousand people in Peru died from cholera linked to

sewage-contaminated seafood

Many human excesses were overmatched by the

vastness of the oceans until the late twentieth century

By the mid-1990’s, production exceeded the estimated

90-million-metric-ton sustainable yield of a wild ocean;

by 2002, the yield had dropped to 63 million metric

tons The best fishing grounds have moved

progres-sively farther from the ports of the fishing fleets, so

production increases are largely confined to the last

frontiers in the Indian Ocean Virtually every fishing

region of the world is overexploited or under

pres-sure

In the 1990’s, the Grand Banks (east of Canada)

began collapsing noticeably In 1992, the Canadian

government halted cod fishing in Canadian waters because there were virtually no cod of spawning age Human-induced climate change will surely and seri-ously affect ocean fisheries and commercial fishing

As warming and cooling surface waters disrupt cur-rents and phytoplankton populations, additional fresh water entering the marine habitat from melt-ice will alter regional salinity; increases in water depths will inundate estuaries and tidal zones, altering breeding and rearing habitats; and deepening coastal waters will drop coral reefs below the vital photic zone, stress-ing their ability to survive

Nonetheless, production has been maintained by various subsidies for bigger and more sophisticated boats going farther and fishing deeper to catch dwin-dling fish stocks Many subsidies are given to fishing fleets simply to help cover the cost of fuel to run the boats and processing operations It is estimated that a cumulative worldwide annual investment of around

$34 billion in subsidies is helping to deplete the global fishery, with the subsidies accounting for 20 percent

of the value of the annual commercial harvest Japan provides the largest annual subsidies to fishers (about

$2 billion) The result of such subsidized fishing is that one-half of all major fish stocks are close to their capable limit, with another 15 percent identified as overfished

The delayed crisis in the marine fishery, when it ar-rives, will probably be painful for the world’s fishing fleets Nations are increasingly limiting fishing by for-eign boats so they can rebuild production Mean-while, unregulated waters are being overfished At some point the collapse of the Grand Banks fishery will be repeated in a number of areas The continued large investment and subsidies of large fishing fleets have increased marine harvests for decades, but in most regions fish harvests have exceeded estimated sustainable yields Fish stocks have collapsed in many regions of the globe and many fishing businesses have gone bankrupt High-gain commercial fishing has devastated some of the most traditionally productive fisheries To meet demands for fishmeal and table fish, fish not previously sought are being harvested at unsustainable rates By the late 1990’s, the U.S gov-ernment had reported that for three hundred species

of harvested fish for which data were available, one hundred were being fished beyond sustainable yields When fish stocks reach critical levels of depletion and unsustainability, many nations put fishing bans into effect In 1992, along the Georges Bank, stock levels

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of haddock, cod, and flounder became so low their

harvest was banned In 2003, Pacific coast rockfish

be-came so endangered an emergency ban on all bottom

fishing was enacted In 2008, Pacific salmon stocks

had become so low a ban on their commercial harvest

was put into place

The loss of viable fisheries has also resulted in

armed conflict between nations As fish stocks

de-crease from overfishing, territorial waters have

be-come aggressively monitored to stop other nations

from harvesting within those zones During the late

1950’s and mid-1970’s, Britain, Iceland, and several

other European countries with commercial fishing

fleets engaged in what has been called “the cod wars.”

Because Iceland is highly dependent on fish exports,

it extended its territorial waters to protect its regional

fish harvests; to ensure its extended boundaries,

Ice-land patrolled the waters with naval gunboats Great

Britain did not recognize Iceland’s territorial waters

claims and sent its own naval warships to support

the British fishing fleets venturing into the disputed

waters These “cod wars” were the

impe-tus for the United Nations Convention

on the Law of the Sea (UNCLOS), which,

in 1982, established global territorial

wa-ters limits and the extent of EEZs During

the mid-1990’s, a similar fishing conflict

between the United States and Canada

resulted in “the salmon war.” While no

naval fleets were involved in “the salmon

war,” back-and-forth retaliatory fishing

quotas and retaliatory unlimited harvest

practices resulted in an intense

diplo-matic battle and, eventually, a Canadian

fishing-boat blockade of an American

ferry in Prince Rupert harbor In 1999,

the two governments signed a treaty to

coordinate management of the Pacific

salmon fishery

Regulation, Aquaculture, and

Mariculture

The mechanized hunting by

unsuper-vised fishing fleets is as inherently

prob-lematic as the whaling and buffalo

hunt-ing of the nineteenth century that drove

these hunted species to commercial

ex-tinction Eventually these fleets will have

to be replaced by regulated fishing and

organized mariculture in which

marine-water-living plants and animals are bred, protected, and cultured As with agriculture on land, this shift will increase production many times

Regulated or rationalized fishing is simply manag-ing ordinary fishmanag-ing so the catch is sustainable Regard-ing the takRegard-ing of freshwater fish, states sell limited numbers of licenses and limit fishing catches Similar limitations are increasingly set within the EEZ Con-trolled harvesting has allowed the Norwegians to main-tain fish production at susmain-tainable yields It should have allowed the United States and Canadian govern-ments to maintain a smaller sustainable yield than they have attempted Ultimately, treaties must apply

to international waters in addition to domestic waters Along with the controlling of production, fish hab-itats must be protected or repaired British Columbia invested in reducing silt runoff from logging, and the reward was a rebound in salmon production Treating some of the world’s presently untreated sewage would have important health benefits for people as well as for fisheries Suggestions have been made that fishing

U.S Aquaculture Production, 2006

Thousands

of Pounds

Metric Tons

Thousands

of Dollars

Finfish

Shellfish

Source: Data from the National Oceanic and Atmospheric Administration,

National Marine Fisheries Association.

Note: Miscellaneous includes ornamental and tropical fish, alligators,

algae, aquatic plants, eels, scallops, crabs, and others.

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rentals or production taxes be used to support

con-trols and habitat improvement They would also help

reduce the excess capacity in the industry

Aquaculture is culturing fish and plants in fresh

water It has been practiced for centuries in Asia In

rice culture, small fish can be raised in the paddies

during the water-covered stage and caught when the

paddies are drained Hatcheries have long been used

throughout the world to increase the numbers of

sport fish or commercially fished species (although

stocking has risks of reducing genetic diversity, and

hence the viability of the wild stocks) From

hatcher-ies, it was a short step to fish farming of salmon, trout,

catfish, carp, tilapia, and shrimp Fish farming is a

fast-growing source of production, having profits of more

than $1 billion dollars per year in the United States

There is some commercial production of

freshwa-ter algae, such as spirulina, which was eaten by the

an-cient Aztecs and is still harvested and eaten around

Lake Chad in Africa As with plankton, the

produc-tion per unit of area is greater than any land plant

Water hyacinths (water lily) and certain other water

plants could also be used for livestock forage and even

for human food Once again, culturing of the plants

could be combined with water animal production

Aquaculture, too, has risks and costs Fish-pond

wastes can pollute neighboring waters, and, as with

stocking, a risk exists of weakening the species by

re-ducing genetic diversity Another risk is that

econom-ics would naturally drive fish farmers toward high

con-centrations of animals, thus increasing the risk of

disease Antibiotics can be used, but routine

antibi-otic use can create antibiantibi-otic-resistant microbes There

are also probable environmental costs; for example,

shrimp farmers in undeveloped countries have often

destroyed mangrove swamps to make their farms,

thus destroying wild stocks of shrimp and other

spe-cies that start life in the mangrove swamps The loss of

the mangroves also makes shorelines susceptible to

devastating erosion from storms

Mariculture is essentially agriculture in the ocean

Once again, Asian countries have pioneered many

processes Some edible plants are cultured on nets

Shellfish such as oysters are grown on ropes

sus-pended from rafts Because they do not touch the

bot-tom, these shellfish are safer from starfish and other

bottom-dwelling predators A few commercial

opera-tions in the West are pioneering fish cages in the open

ocean, where vast distances allow nearly unlimited

clean-water input and waste disposal Australia has

several successful open-ocean operations for the rear-ing of tuna

More speculative proposals for the future include vast networks of cables and netting that would provide holdfast points for near-shore plants such as kelp Beds of plants, in turn, would provide food and habi-tat for sea animals Such marine planhabi-tations could

be fertilized by chemicals or perhaps by artificial upwellings connected with oceanic power stations While aquaculture and mariculture help provide fish and seafood, the fish-feed required for this type of operation to be successful puts pressure on wild fish-eries It requires almost 1 kilogram of fishmeal de-rived from wild fish to produce one-half kilogram of farmed salmon In 2001, fish farming required one-third of the world’s production of fishmeal Estimates indicated that this proportion was approaching one-half in 2010

Roger V Carlson, updated by Randall L Milstein

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