California Condor

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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

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