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 ince colonial times, wildlife in America has faced
two periods of crisis, one at the close of the 19th century,
the other at the close of this century. And yet, these times
of crisis have also been times of great hope for the future of
our embattled wildlife.
 The
last quarter of the 19th century witnessed the end of the last,
great flocks of passenger pigeons and herds of bison, the near-extinction
of sea otters, ruthless campaigns to rid the West of its wolves,
grizzlies, and other large predators, and insatiable commercial
markets for the feathers and flesh of all manner of birds. The
modern environmental movement began in response to this destruction
of wildlife, and thankfully succeeded in stopping some of the
worst abuses. Today, a network of national wildlife refuges,
parks, and forests, as well as numerous laws and treaties, provide
a safety net of sorts for American wildlife.
As we approach
the end of this century, as much as a third of our total flora
and fauna is currently in danger of extinction -- more than at
any time since the end of the Ice Age. Over-exploitation -- the
bane of conservationists at the turn of the century -- is no
longer a major threat to most animals (with the notable exception
of some fisheries). Instead, it has been replaced by three far
more ruthless and indiscriminate killers: habitat destruction,
nonnative or alien species, and pollution.
It's a grim
situation, but by no means a hopeless one. A new Executive Order
from the White House is designed to curb the accidental or intentional
release of foreign plants and animals in the United States. Reducing
this "alien invasion" will go a long way toward preventing
many plants and animals from becoming endangered. The White House
and Congress are both talking about creating a permanent source
of funding for the starved Land and Water Conservation Fund,
which would be used to purchase new parks and open space. The
US Fish and Wildlife Service has instituted a "safe harbor"
program that allows landowners to restore habitats for endangered
species without incurring additional regulatory burdens; thus
far, over a million acres of land have been enrolled in the program.
As the yearand
the centuryand the millennium draw to a close, it's time to look
back on the species that have done well and the ones that haven't.
In that spirit, here's our list of America's Wildlife Winners
and Losers of the Twentieth Century:
Wildlife Winners of the Century
1. Bald eagle
The
widespread use of DDT and other persistent pesticides in the
years after World War II caused populations of bald eagles, peregrine
falcons, ospreys, and other birds to crash. The pesticides interfered
with the birds' reproduction, causing them to lay infertile eggs
or eggs with shells so fragile they collapsed under the weight
of the incubating parent. The bald eagle population in the Lower
48 dropped to fewer than 450 pairs in the 1960s, and the eagle
was added to the endangered species list in 1967. The banning
of DDT, coupled with the protection of nesting sites and reintroduction
programs made possible under the Endangered Species Act, set
the stage for the eagle's recovery. In 1998, the breeding population
of eagles in the Lower 48 totaled 5,748 pairs. This past summer,
the Interior Department announced that it would remove the eagle
from the endangered species list, an auspicious beginning for
the new millennium.
2. White-tailed deer
As improbable
as it seems today, the white-tailed deer was in danger of disappearing
from large parts of the United States at the beginning of the
20th century. Unregulated hunting, combined with extensive deforestation,
had eliminated deer from most of their historic range. Fewer
than half a million remained in the nation. The imposition of
game laws, the regeneration of the eastern forests, and (unfortunately)
the extirpation of major deer predators such as wolves and mountain
lions, allowed this graceful animal to stage one of the century's
biggest comebacks. Today, some 17 to 25 million whitetails prowl
the forests, fields, and suburbs of America. In many areas, white-tailed
deer have become so abundant that they are now pests, destroying
farm crops, consuming backyard vegetable gardens, decimating
native wildflowers, and impeding the regeneration of forests
by consuming young hemlocks and yews.
3. Brown-headed cowbird
Like
the white-tailed deer, the brown-headed cowbird is an example
of a native species that has succeeded all too well. A member
of the blackbird family, the cowbird is a brood parasite -- it
lays its eggs in the nests of other bird species, at the expense
of the hosts' own eggs and offspring. Prior to the arrival of
European settlers, cowbirds were largely confined to the central
plains, where they followed the roaming herds of bison, eating
the insects stirred up by them. The clearing of the forests for
pasture and farmland, as well as the introduction of domestic
livestock, enabled cowbirds to spread to new areas and increase
in abundance. The expansion of rice farming in the South also
has benefited cowbirds by providing them with an abundant new
food source for the winter: waste grain left in the fields after
harvest. More cowbirds, of course, mean that more nests of other
birds are being parasitized. In recent decades, cowbird parasitism
has been a key factor in the near-extinction of the Kirtland's
warbler, black-capped vireo (see "Wildlife Losers"),
and least Bell's vireo. The survival of all three species now
depends upon ongoing efforts to control cowbird numbers in key
breeding areas. In addition, cowbird parasitism is thought by
many scientists to be one reason why populations of forest-dwelling
warblers, vireos, tanagers, and other songbirds have been declining
in many parts of the East.
4. Gray wolf
Prior
to the arrival of settlers from Europe, gray wolves occurred
from Alaska to Mexico, and from the Atlantic to the Pacific.
They were hated and feared by most settlers, who persecuted them
with a vengeance. By 1960, the only wolves remaining in the United
States were in Alaska and northern Minnesota. Protection under
the Endangered Species Act enabled the Minnesota population to
grow and expand; it also allowed a few wolves to move safely
south from Canada and recolonize the northern Rockies. In 1995,
after years of prodding from environmentalists, the federal government
reintroduced wolves in Yellowstone National Park and in wilderness
areas of central Idaho. The results have been spectacular: more
than 200 adult wolves now roam the wildlands of Yellowstone and
central Idaho, and last spring, about 120 pups were born in the
two areas. Tourists from around the world have been flocking
to Yellowstone to catch a glimpse of them. The reintroduction
of the gray wolf has cost less, succeeded better, and generated
fewer conflicts with livestock than virtually anyone predicted
when these efforts began.
5. Gray whale
One
of the easiest whales to hunt because of its slow speed and preference
for inshore waters, the gray whale was driven close to extinction
by whalers. A population along the Atlantic coast vanished in
the early 18th century; another population in Asia has been reduced
to a few hundred individuals; and a third population along the
Pacific coast of North America -- the well-known population that
migrates from feeding grounds in the Bering and Chukchi seas
to breeding grounds off the coast of Baja California -- numbered
no more than a few thousand at the start of the 20th century.
Protection for this Pacific coast population has enabled it to
stage a remarkable recovery. It is now estimated to number 23,000
individuals, which is equal to if not greater than the population
prior to exploitation. The Pacific gray whale was taken off the
endangered species list in 1994.
6. Northern elephant seal
From
the blubber of a single 18-foot elephant seal, a seal hunter
could extract more than 210 gallons of oil, which was used to
fuel lamps. For this reason alone, North America's largest seal
was brought to the brink of extinction. By the start of the 20th
century, fewer than 100 individuals were left. Protection came
not a moment too soon. Today, over 125,000 elephant seals crowd
the beaches of California and Baja California, earning this species
the title of "comeback kid of the century."
7. Whooping crane
Our
tallest bird has been the subject of what is perhaps the longest
running and highest profile conservation effort for any imperiled
species in the United States. Whooping cranes once nested on
the northern prairies south to present-day Iowa and Illinois,
with scattered numbers elsewhere in the Southeast, but hunting
and the destruction of wetlands took a heavy toll on them. By
the 1940s, approximately 20 cranes remained. The whooping crane
was added to the endangered species list in 1967. Aggressive
enforcement of the Endangered Species Act's stiff penalties against
killing cranes, protection of the birds' winter habitat along
the Texas coast and their migratory stopover sites along the
Platte River, and a captive breeding program have all been used
to bolster the population. More recently, federal and state officials
have attempted to create a new, non-migratory population of cranes
in Florida. As a result of all these efforts, the wild population
of whooping cranes now exceeds 250, which is probably more than
at any time this century. Although the whooping crane is by no
means out of danger, it nonetheless represents one of this century's
greatest success stories in wildlife conservation.
8. Cheatgrass
Among
the nation's least-loved species, cheatgrass is nonetheless one
of this century's biggest winners. Native to the Old World, it
was accidentally brought to the United States and Canada in the
late 1800s. Once on this continent, cheatgrass "rode the
rails," dispersing its seeds via grain shipments, livestock
feed and bedding, and animal dung. Its spread was also facilitated
by threshing machines, which were moved from farm to farm without
being cleaned. In some places, range experts even planted it
deliberately in order to replenish overgrazed rangelands. Cheatgrass
is a highly flammable plant that dies and dries out in the spring,
creating ideal fuel for summer wildfires. The summer fires, in
turn, sweep through the shrublands, killing or damaging native
plants, and creating new opportunities for the cheatgrass. Inventories
show that cheatgrass currently dominates tens of millions of
acres of what was once sagebrush steppe in the West. Alien species
like cheatgrass are second only to habitat degradation as a cause
of (native) species endangerment in the United States -- and
more unwelcome plants and animals are crossing our borders every
year aboard planes, trains, ships, and automobiles.
Wildlife Losers of the Century
1. Passenger Pigeon
Once
the most abundant bird on the planet, with flocks that literally
darkened the sky, the passenger pigeon was the victim of relentless,
ruthless overhunting, coupled with the clearing of the eastern
forests. By the end of the 19th century, it was on the brink
of extinction. And less than one hundred days into the new century,
on March 24, 1900, the last wild passenger pigeon was killed
in Pike County, Ohio. The last captive individual, an aged female
named Martha, died at the Cincinnati Zoo on September 1, 1914.
Today all that remains of this once-abundant species are the
written accounts of the early naturalists, a few stuffed specimens,
and the term "stool pigeon," which once referred to
passenger pigeons that were captured and tethered and used to
lure other passenger pigeons to the ground where they could be
netted.
2. Turgid-blossom pearly mussel
This
obscure little creature, now believed extinct, stands for something
more: the wholesale destruction of America's freshwater fauna
over the course of this century. In general, our freshwater species
-- fish, mussels, dragonflies, etc. -- are disappearing at a
much faster rate than our terrestrial species, despite laws like
the Clean Water Act. Approximately two-thirds of North America's
freshwater mussels, for example, are either extinct or gravely
imperiled. The turgid-blossom pearly mussel once inhabited twelve
rivers in Arkansas, Missouri, Tennessee, and Alabama, but river
impoundments, siltation, and pollution steadily reduced its range.
In the early 1970s, the last known population lived in the upper
reaches of the Duck River, in central Tennessee, precisely where
the Tennessee Valley Authority intended to put a dam. Most freshwater
mussels cannot survive in the murky, still waters that are created
by dams. The US Fish and Wildlife Service, unwilling to block
the construction of the dam for the sake of a rare mussel, delayed
putting this species on the endangered list until after the dam
was completed. By that time, of course, it was too late: the
turgid-blossom pearly mussel was gone.
3. Snake River sockeye
The
poster child for the Northwest's dwindling salmon populations
may well be the Snake River sockeye. Historically, few salmon
traveled as far or climbed as high as the intrepid sockeyes of
the Snake River, which for countless generations journeyed 900
miles from the Pacific Ocean through the Columbia River and up
the Snake River to their ancestral spawning grounds in Idaho's
Redfish Lake. A difficult journey in the best of times, it has
become a near impossibility in recent decades due to dams, water
diversions, logging, grazing, and other activities that have
degraded and destroyed salmon habitat. By the time the Snake
River sockeye was granted protection under the Endangered Species
Act in January 1992, the population was down to a handful of
individuals. A captive breeding program is underway, and state
and federal authorities have promised to take action to improve
salmon habitat. Whether these actions will be enough to halt
or even reverse the decline is open to debate. At the present
time, the future of the Snake River sockeye, and that of many
other salmon stocks in the Pacific Northwest, looks bleak.
4. Bobolink
According
to scientists at the Interior Department, North America's grassland
birds have shown steeper and more widespread declines over the
past quarter century than any other group of birds. The bobolink,
a colorful member of the blackbird family, is a case in point.
Occurring in hay fields, grasslands, and pastures across much
of the United States, it is declining in most of its range. In
Illinois, for example, bobolinks declined by a staggering 93
percent between 1966 and 1991. This sharp drop can be attributed
to two factors: the conversion of pastures and hay fields to
row crops, and a trend toward cutting hay fields earlier in the
season, when the bobolinks are still nesting. There is some cause
for optimism, however. The Department of Agriculture's Conservation
Reserve Program pays farmers to retire tens of millions of acres
of highly erodible soils from crop production and plant them
with cover (mostly grass). Bobolinks and other grassland birds
have found much of this newly restored habitat to their liking.
5. Black-tailed prairie dog
The
four species of prairie dogs that inhabit the grasslands of western
North America are critical components of those ecosystems. By
creating a vast network of burrows and by continually clipping
the grass around their colonies, prairie dogs create a diversity
of habitats supporting many other species of plants and animals.
Among the animals associated with prairie dog colonies are a
number of rare and declining species, including the black-footed
ferret, swift fox, mountain plover, sage grouse, and burrowing
owl. The settlement of the western grasslands had severe consequences
for prairie dogs due to poisoning, land conversion, and overgrazing
by livestock. Of the four species, the black-tailed was by far
the most numerous. In its heyday, it occupied more than a hundred
million acres of the central plains along the eastern side of
the Rockies, from Canada to Mexico. Its total population must
have numbered in the hundreds of millions, if not billions. Since
settlement of the West, it has suffered a 98 percent reduction
in range and now survives only in scattered locations. It is
being considered for listing as a threatened species. Ranchers
continue to exterminate prairie dogs throughout the West, under
the belief that these animals compete with livestock for forage.
Yet studies show that prairie dogs actually prevent shrubs from
encroaching on grasslands, thereby benefiting the ranchers. Moreover,
their habit of clipping the grass around their colonies improves
the quality of the grass and forbs for livestock. Prairie dogs
also are shot for "sport" and target practice.
6. Po'ouli
In the
summer of 1973, two students from the University of Hawaii stunned
the ornithological world when they discovered a previously unknown
species of songbird living in the remote rainforests of Maui.
The po'ouli was the first new bird species to be discovered in
the United States since the beginning of the century. Estimates
placed the total population at around 140 individuals, all occurring
within an area of rainforest totaling less than 2 square miles.
In recent years, however, the po'ouli population has crashed,
probably because feral pigs have destroyed much of the vegetation
where the birds live. Diseases spread by nonnative birds brought
to the Hawaiian Islands by well-meaning people may be contributing
to the decline as well, along with predation by rats. The most
recent census turned up only three remaining po'ouli, and the
species seems destined for extinction in the near future. To
some degree, however, the demise of the po'ouli comes as no surprise:
The Hawaiian Islands have one of the highest proportions of extinct
or endangered species of any comparably sized area on earth.
The reason for this epidemic of extinction is a combination of
habitat destruction and the widespread release of nonnative or
alien species.
7. Black-capped vireo
At the
turn of the century, black-capped vireos could be found in shrublands
from central Kansas south through Oklahoma and Texas into northern
Mexico. But, like many other songbirds, it is a prime target
of the brown-headed cowbird (see "Wildlife Winners"),
which parasitizes the nests of other birds. Heavy rates of nest
parasitism by cowbirds, coupled with the destruction and degradation
of its shrubland habitat by developers and livestock, landed
the black-capped vireo on the endangered species list in 1987.
Today, the only sizeable populations left in the United States
occur in the Hill Country of Texas. Fortunately, cowbird control
programs in a number of key vireo nesting areas have dramatically
reduced the rate of nest parasitism and allowed vireo populations
to expand. A loser in the 20th century, the black-capped vireo
may well emerge a winner in the 21st.
8. Longleaf Pine
When
the Spanish began exploring North America in the 16th century,
nearly pure stands of stately longleaf pines covered about 74
million acres in the southeastern coastal plain, from Virginia
south to Florida and west to Texas. Frequent summer wildfires,
spawned by lightning storms or set by Indians, kept oaks and
other hardwoods from crowding out the fire-resistant longleaf
pine. Today, less than 3 percent of the original longleaf pine
forest ecosystem remains, and most of that is in a highly degraded
condition. Four factors contributed to the demise of this uniquely
American ecosystem. First, at the turn of the century, the longleaf
forests were heavily logged but not replanted with longleaf pine.
Other species of trees then grew up on these sites. More recently,
much of the remaining longleaf forest has been harvested and
replaced with other, faster-growing pine species preferred by
the forest products industry. Second, prior to the development
of petroleum-based substitutes, settlers used the tar, pitch,
rosin, and turpentine of longleaf pines to lubricate wagon axles,
waterproof sails, caulk leaks, and protect the hulls of ships
against shipworms; vast acres of long-leaf pine trees were literally
bled to death. Third, for much of the 19th century, large numbers
of feral hogs roamed the South, eating longleaf seedlings. Finally,
due to fire suppression, much of the remaining acreage of longleaf
pine has become overgrown with hardwoods. Numerous plants and
animals associated with the longleaf pine ecosystem have suffered
severe population declines due to demise of these forests, foremost
among them the endangered red-cockaded woodpecker.
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