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California Condor Essay, Research Paper
The natural
environment of the modern world has been under siege for the better part of the
past century. This has been due to many factors. The waste produced by an
ever-expanding human population has tainted much of the natural resources
available to both humans and animals alike. Efforts to curb this waste output
and to more effectively dispose of the waste have failed in the mainstream. The
constant change of the common environment instituted by humans who have
collectively sought to modify their own habitat has exacted a high toll on the
available habitat for lesser creatures. Constant waste production, poor
disposal, and habitat encroachment have combined to render the balance of the
natural world asunder. ?The delicate and intricate balance of the natural
world has been damaged by a dominant species that has commonly disregarded its
inherent responsibility to garnish its actions concurrent with the world it
shares with the rest of nature? (Center for Reproduction of Endangered
Species. p3). An all too common result of this imbalance is the expiration of
entire species of animals that are dependent on precious resources.
Historically, the presence of humans McNulty 2 has exponentially accelerated the
natural rate at which fringe species have met with extinction. Modern humans
have followed their own ancient precedent in this regard. ?Recorded evidence
of early human settlement has shown that human presence alone had accelerated
extinction rates to several times its natural rate? (Center for the
Reproduction of Endangered Species. p4). However, it is a different precedent
that modern humans have sought with the advent of a new and more complete
awareness of our collective role as the dominant species. Several recent
advances in waste treatment are offering alternatives to the usual high-output,
wasteful societal paradigm. Although habitat encroachment continues to be a
source of great conflict between the human population and the animal world, the
human race has begun in earnest to attempt restoration of some species that have
fallen casualty to pollution, encroachment, or both. Although success has been
limited, these restorative efforts represent a reckoning on the behalf of humans
with their place in the natural order. One of the most successful of these
programs concerns the California Condor. This magnificent species had all but
disappeared from its natural range due to the human presence. With the recently
recorded demise of the California Condor?s natural population came the effort
to repopulate selected areas of habitat with captively breed condors. McNulty 3
THE STUDY OF THE CALIFORNIA CONDOR The California Condor is a remarkable species
of scavenging birds indigenous primarily to California. Early studies showed
populations of condors ranging from the rocky coastal areas to the interior
mountains. In the early 1900s, sightings of these majestic birds, although
reclusive in nature, were commonplace. Early in the 1900s, serious scientific
studies began on the California Condors. There were many successful studies in
the wild, and there was increasing interest from the scientific community. In
1939, the naturalist Carl Koford first began a careful scientific study of these
condors in the wild. Carefully documented field studies yielded a wealth of
information about a species in the American West that had previously eluded the
scientific eye. One development resulting from the study of Carl Koford was the
establishment of the exact nature of the diet of these birds. Although known to
be primarily scavengers, it was learned just how well adapted these birds are at
finding and discriminating suitable prey. It was learned that the primary
feeding times were during daylight hours, with most activity centering near
noon. They were observed feeding on carcasses in all states of decay, and even
competing with other more aggressive species for rights to a kill. Their bills
are exquisitely adapted to tearing animal flesh, and their digestive systems are
specially suited to digesting rotting flesh. Condors were not known to have
attacked live prey, and the diet of condors was found to have been an assortment
McNulty 4 of carcasses found throughout the feeding range. ?Condors were found
to have spent an average of fifteen hours a day at the roosting site, and even
more hours on days of inclement weather? (Grossman. p38). These studies also
produced the first scientific measure of the social structure of these birds.
Their population had come under suspicion during this time, and the population
count during this time seemed to prove their decline. The territories of these
birds were found to be wide stretching, often including several hundred miles.
The ability of these birds to roam these territories in search of food was found
to be incredible, with some specimens gliding on large wings as far as ten miles
with no wing movement. Poor weather and still air had been found to restrict the
birds to the nesting site. In optimum conditions, making use of thermal updrafts
for efficient flying was found to be common among these birds. This mobility was
shown to provide another advantage with the remains of coastal marine molluscs
found near some nesting sites during the study. In combination with the diet of
these birds, this mobility led to conflict with the ranching efforts of humans.
Many ranchers began making a misguided effort to protect their livestock by
regularly shooting condors even though condors are scavengers, and are not
hunters of live prey. Further, sport shooting went largely unregulated for
years. Some other developments included establishing the nature of the
reproductive biology of the condors. These birds were observed as cavity
dwellers. ?Nesting in rocky caves, crevices, or among boulder formations,
these condors were found to move to new sites between nesting attempts? (The
Encyclopedia of Birds). This was deemed to be part McNulty 5 of the habitat
needs these birds required. The incubation period of these birds was found to be
fifty-four to fifty-eight days, with each parent taking turns guarding the nest.
The fragility of these birds was attributed in part to their low birth rate.
?A mature female will lay one egg only every two years, and the young are fed
throughout most of their eighteen to twenty month adolescence. Although a chic
begins flight practice at five to six months of age, the dependency on the
adults for food can continue into the second year? (Audubon?s Birds of
America.). This reproductive profile rendered the condor population sensitive to
hunting and encroachment because they required so long a period of time to
regenerate losses in population. ?The effects of industrial chemical pollution
further complicated regeneration of losses. Industrial chemical pollution has
been proven to be destructive with studies having shown that the eggshells of
condors were reduced in thickness by as much as thirty percent after the
widespread use of DDT? (MacMillan Illustrated Encyclopedia of Birds).
CONSERVATION EFFORTS FOR THE CALIFORNIA CONDOR With the knowledge gained from
successful field studies, scientists began to consider solutions to the
dwindling wild population of California Condors. Captive breeding was an idea
that garnished considerable attention from the general scientific McNulty 6
community. Two scientists from the San Diego Zoo proposed a captive-breeding
program aimed specifically at regenerating the wild population of California
Condors. The San Diego Zoo Director Belle Benchley and Curator K.C. Lint had met
with considerable success with a captive breeding program aimed at breeding
Andean Condors through a technique known as double clutching. This involved
removing eggs from captive breeding pairs, thereby stimulating the female to lay
one egg every year. The doubled egg laying rate offered potential for
regeneration of numbers faster than a naturally breeding pair. Pressure from
environmental groups eventually prevented the proposed program from going into
action with the overriding concern being disturbance of the remaining pairs in
the wild. The attention devoted to the preservation of the California Condor
experienced a resurgence in nineteen sixty-six when the California Condor
appeared on the first published list of endangered species. The population
estimates ranged from fifty to sixty birds. The population continued to decline
and in nineteen seventy-nine estimates ranged from twenty-five to thirty-five
birds in the wild. There was increasing pressure from the California Fish and
Game Commission, The Audubon Society, and the US Fish and Wildlife Service to
implement an aggressive program to save the remaining condors. Two years later,
a positive observation was made by biologists of California Condors laying
replacement eggs after losses of first laid eggs at remote nesting sites. This
provided additional credence to the idea of using the double clutching technique
with McNulty 7 captive pairs to regenerate the species. The Condor Research
Center was granted license to attempt deliberate placement clutching or condor
pairs to aid in a captive-breeding program. Several years passed with continuing
efforts to begin captive breeding resulting in the first captive hatch in March
of nineteen eighty-three. By this time, the wild population was estimated to be
nineteen birds. By nineteen eighty-five, this continued decline of the wild
breeding population coupled with the initial captive breeding success resulted
in approval of a plan to capture the remaining wild birds for captive breeding.
The remaining nine wild birds were captured, and the breeding program expanded.
Eventually, artificial incubation began as part of the regeneration effort. The
artificially incubated eggs hatched at nearly twice the rate of eggs studied in
the wild. This high success rate lent further credence to the once controversial
intervention in the name of species regeneration. The proper care of the captive
birds was the purpose behind the design of the captive breeding facility. The
first facility was called the Condorminium, and was designed as an enclosure
that would allow the most natural setting possible. This was concurrent with the
final goal of reintroduction. The facilities used for this captive-breeding
program were designed to allow limited flapping and mobility for the birds, thus
mitigating the stress of captivity. Constructed in an area of access to wind and
some weather, these enclosures helped to preserve some sense of instinct. To
further maintain a healthy environment, the enclosures were strictly off limits
to the public. Enclosures used McNulty 8 in this program were installed in
several regions of the American West, with pairs being raised in San Diego,
Boise, and eventually Los Angeles. The success of this program was to be
measured by the release of breeding pairs of condors that were bread in
captivity. There were several problems to be addressed in this process. One
question was how to ensure that the condors to be released would have the
benefit of human aversion. Minimizing human contact during the rearing stage was
one measure stipulated in the program outline. Negative reinforcement training
was widely used to condition captive birds with the skills needed to succeed in
the wild. Aversion training was also used in an attempt to preclude accidental
injuries after release. The natural curiosity of condors can lead wild condors
near population centers, often to perch on power lines. Aversion training aimed
at preventing such roosting can include presenting captive birds with a
combination of trees and mock telephone poles to perch on. If the birds choose
to perch on the mock poles rather than on the available trees, they are provided
negative reinforcement by way of a mild shock. These techniques are in place to
afford captive birds every opportunity for success upon release. The release
program continued to grow, with multiple pairs gaining release between nineteen
ninety-three and nineteen ninety-seven. The first release site was in the Los
Padres National Forest in southern California. There were two separate release
points constructed there in response to an increase in human activity and power
lines. There was a second release point used in Lion Canyon, which is also in
the Los Padres National Forest. Subsequently, a site thirty miles north of the
Grand Canyon called Vermillion McNulty 9 Cliffs was chosen as a release site
because of its unique landscape and remote location. The success of the released
condors has proven encouraging. There are four areas now populated by released
breeding pairs, and future releases are planned at regular intervals.
Maintenance of released birds includes baiting designated feeding areas with
carcasses to encourage the birds to learn to scavenge. This requires regular
placement of food with careful avoidance of any human contact in order to help
preserve the bird?s natural searching instinct. Many questions remain about
the future of these birds, but the regeneration of the wild population continues
to benefit from the captive breeding programs. LIMITATIONS OF CONDOR CAPTIVE
BREEDING Captive breeding programs represent a concerted effort on behalf of
humans to sustain the species that have been gravely affected by the changes in
environment bought about by the actions of mankind. Many people accept programs
such as these as progress toward mending the damage inflicted by humans on the
environment. There are, however, several fundamental questions that are going
unanswered. First, does answering the slow regeneration problem through captive
double clutching fix the problem of extinction or simply delay a symptom? It is
important to recognize that the numbers of wild condors were diminished to the
point of near extinction as a result of human destruction of habitat. Through
pollution and McNulty 10 encroachment, humans have permanently changed the
environment. Slowing this rate of change is central to any solution if we are to
attempt to reach equilibrium with nature. Second, can the collective actions of
the human race be changed sufficiently for the continued survival of fringe
species? Evidence has shown that conflict between fragile species and the
agricultural settlement of common habitat inevitably leads to the decimation of
the species in question, in this case the California Condor. The solution to
this element of the problem is perhaps the most elusive. This cannot be answered
by resettlement or repopulation. The actions of the human race must become
responsible on the individual level. Education about endangered species and
federal protection of endangered species can help, but the questionable future
of fragile species can be made more certain only by responsible actions on the
part of individuals. Additionally, can humans share common land with wild
scavengers with out justification for needless hunting? Many people do not see
why humans should try to share resources with a competing species. This leads to
perhaps the most central question concerning conservation in general. Why
conserve? Many average people fail to see the fault in the actions of humans as
the dominant species on the planet when annihilate subordinate species. If there
exists a conflict between human interests and the needs of a competing species,
then why accommodate a lesser-developed animal? The answer can only be found in
the idea that humans have a responsibility to preserve the natural order.
Perhaps best answered by McNulty 11 a Park Ranger with whom I had the
opportunity to speak about this very issue, ?saving weak species may seem like
a waste of time to some people, but as soon as we give up on a single species,
we have started down the wrong path?. Humans, as a race, benefit from natural
preservation in the projected future. Long term preservation of natural
resources, plant, mineral, and animal alike, is an idea that holds little merit
with a majority of humans who are often faced with more immediate concerns for
their own well being and welfare. Balancing immediate needs and long term
interests is one challenge facing the human race as resources become more scarce
and human needs grow with our population. If we are to collectively survive as
members of an intricate ecosystem, we must learn to manage our natural dominance
toward the good of the planet. McNulty 12
?New World Vultures.? Macmillan Illustrated Animal Encyclopedia. 1984 ed.
p216 ?Condors and Vultures.? Audubon?s Birds of America. CrossRiver Press,
1981. p89 Grossman, Mary Louise. Birds of Prey of the World. Clarkson N. Potter,
1964. p37-39, 203-204. ?Birds of Prey- The Raptors.? The Encyclopedia of
Birds. 1985 ed. p103-104 ?California Condor Conservation Efforts.? Center
for Reproduction of Endangered Species. 1 April 2000. pp1-5. San Diego Zoo. 8
April 2000. *http://www.sandiegozoo.org/cres/milestone.html*. ?Condor
Reproductive Biology.? Center for Reproduction of Endangered Species. 1 April
2000. pp 1-4. San Diego Zoo. 7 April 2000. *http://www.sandiegozoo.org/cres/reproductive.html