|
April
2006
Empty Nest Syndrome: The Impacts of Meat on Bird Populations
By Monica Engebretson
|
Habitat loss is well recognized
as the single greatest overall threat to birds, outweighing the impacts
of building collisions, domestic cat predation and human recreational
hunting. Yet conservationists often overlook or simply ignore the role
a particular human custom has in causing habitat destruction.
Mistakenly, most people believe that urban sprawl is responsible for
the largest loss of wildlife habitat in the United States. In actuality,
two crops, corn and soybeans—95 percent of which are fed to livestock—impact
more of the nation’s land area than all urbanization, rural residential
development, highways, railroads, commercial centers, malls, industrial
parks and golf courses combined. Keeping meat on our plates is one of
the leading forces in declining wild bird populations.
Forty years ago Rachel Carson discovered why spring had grown silent:
DDT was killing off wild bird populations. Her book Silent Spring raised
awareness and led to the eventual ban of DDT in the U.S. Today, wild
birds suffer from a different threat with the same outcome.
Raising a Beef
All things considered, meat is by far the least efficient way to produce
protein for our burgeoning human population. In a report prepared by
the Union of Concerned Scientists, meat placed second only to automobiles
in a list of the most environmentally damaging products. The products
were analyzed for their effect on global warming, air and water pollution,
and the alteration of natural habitats. A Worldwatch Institute report
notes that a full 70 percent of all grain grown in the U.S. is used to
feed farm animals. Another Worldwatch report indicates that it takes
two pounds of grain to produce one pound of chicken, four pounds to produce
one pound of pork, and six pounds to produce one pound of feedlot-raised
beef.
Given these statistics, it’s easy to see how some consumers have
erroneously assumed that range-fed beef is ecologically superior to feedlot-raised
beef. Studies show, however, that grazing has caused more damage to western
public lands than any other single activity. Range-fed cattle pollute
streams with urine and feces; introduce and spread exotic weeds; and
trample riparian ecosystems, nests and nesting sites.
The Bureau of Land Management has estimated that 80 percent of western
riparian habitats (areas generally rich in bird species) have been damaged
by livestock. While livestock watering troughs can be used as an alternative
to riparian areas as a means of providing water to cattle, such troughs
often serve as watery death traps for songbirds who drown while attempting
to drink from them. In just a few weeks, a single trough can kill as
many as 49 migratory songbirds.
Another major impact of grazing has been the clearing of sagebrush from
its historic range. Ranchers and farmers have long vilified sagebrush
for choking out “cattle grass” or for getting in the way
of alfalfa and other livestock feed crops. Healthy sagebrush habitats
harbor nearly as many species as riparian habitats, including 94 species
of birds. The bird species most notably impacted by the sagebrush habitat
destruction are the Greater and Gunnison sage grouse, the latter of whose
population has been reduced to an estimated 4,000 individuals. The solution
to the sage grouse’s woes is clear. According to Andy Kerr, advisor
on sagebrush issues to American Lands, a nonprofit land conservation
organization: “The way to protect the sage grouse is to conserve
and improve the habitat, and the primary way to do that is to remove
livestock.”
Global Consequences
The impacts of livestock grazing are not limited to North America. In
Latin America, the conversion of forests and other natural habitats to
cattle ranches is considered the single biggest threat to biodiversity.
Worldwide, grazing is a major cause of desertification—the creation
of desert-like conditions where the soil cannot sustain natural productivity.
Because forests store vast amounts of carbon, typically absorbing 20-50
times more than crops and pastures do, not only does clearing land for
livestock production or feed grain destroy habitat, it contributes to
global warming. Further adding to the greenhouse effect, animal wastes
at feedlots and factory farms emit an estimated 35 million tons of methane
gas—the second foremost greenhouse gas—each year, and ruminant
animals release an additional 80 million tons of methane per year through
belches and flatulence.
Some analysts have estimated that the price of meat would double or triple
if the full ecological costs—including fossil fuel combustion,
groundwater depletion, agricultural chemical pollution, and methane and
ammonia emissions—were included in the bill. Cutting the average
household’s consumption of meat (both red meat and poultry) in
half would reduce food-related land use and common water pollution by
30 and 24 percent, respectively.
But the impact of meat consumption on global bird populations is not
limited to terrestrial habitats. Each year, thousands of albatrosses
are caught and drowned by the baited hooks towed behind longline fishing
boats that target tuna, swordfish and shark for human consumption. Longline
fishing is now considered a significant threat to almost all of the 24
recognized living species and subspecies of albatross.
Despite the availability of bird scaring devices and other fishery management
techniques that can reduce seabird mortality, Alaskan longline fisheries
killed 4,094 birds in 2002 and Hawaiian-based longliners took 116 albatrosses
in 2002. Moreover, longline vessels formerly based in Hawaii and the
Gulf of Mexico have evaded regulations aimed at protecting seabirds and
sea turtles by fishing beyond the 200-mile Economic Exclusion Zone and
landing their catches in California. This legal loophole resulted in
the deaths of 450 Black-footed albatrosses and 17 Laysan albatrosses
between October 2001 and February 2003. Clearly, the fishing industry
is no friend to seabirds.
Also at risk due to humanity’s desire for animal flesh are mangrove
wetlands, which serve as prime nesting and migratory stopover sites for
hundreds of bird species. At least half of the world’s mangrove
forests have been destroyed; one of the top reasons for this destruction
is the construction of shrimp ponds. To cash in on the rising demand
for farmed shrimp, Brazil was expected to cover approximately one quarter
of its coastal wetlands with shrimp ponds by 2005.
Making the Connection
While the collective impact of meat production on global bird populations
far outranks any other human-driven impact—including bird-kills
due to communication tower collisions and predation by domestic cats—the
subject of human dietary choices has received little or no attention
from wild bird conservationists.
Why the collective silence?
Perhaps because the environmental impacts of the meat industry are spread
out over a wide range of seemingly indirect effects on wild birds. It
is much easier, for example, to make the life-and-death connection between
a dead bird at the foot of a communication tower or between the jaws
of a domestic cat than it is to make the connection between the meat
on our plates and the wild birds and habitat destroyed to put it there.
Or perhaps this issue receives so little attention because it is more
comfortable to place the blame for declining bird populations on an inanimate
structure or on another species rather than on our own daily dietary
choices.
Whatever the reason, the fact is that by reducing or eliminating consumption
of meat, those concerned with protecting wild birds can help ease pressures
on land and ocean ecosystems at every meal. It’s time wild bird
conservationists step up to the plate and take a hard look at what’s
on it.
Monica Engebretson is Senior Program Coordinator
for the Animal Protection Institute and an exotic bird specialist. For
more information contact www.api4animals.org.
|
|
© STEALTH TECHNOLOGIES INC. |
|
|