What Problems May Arise By Manipulating Estrous In Animals
ISSUE AND DEBATE
ISSUE AND Fence; SHOULD Human Manipulate ANIMALS?
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July iii, 1984
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Section C , Folio
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THE beautiful trumpeter swan retreats from man's presence while the cockroach and mosquito come up nearer. Plants and creatures beneficial to humans thrive in remote places only rats and mice infest the cities. To many practical- minded people these facts signify that nature's distribution of plants and animals on the globe is haphazard and often detrimental. Every bit a result homo has often taken information technology upon himself, for a variety of conservation or esthetic reasons, to manipulate wild animal and plant species and their environments.
Whooping crane eggs accept been placed in sandhill crane nests. Young California condors have been taken from their mountain aeries and raised in captivity. Mongooses have been moved to areas alien to them, rabbits take been introduced into Australia, wild turkeys resettled in the northeastern The states, beavers transported back to ancient haunts. Even endangered plants are now being bred in captivity.
The purposes of such experiments include saving endangered species from extinction, eradicating pestiferous creatures by introducing a predator species, promoting the proliferation of ''good'' animals or plants, introducing exotic species from far-off places into new sites more accessible to humans, and aiding the hunters of wild game.
Some of these efforts have been successful, some have failed or have brought virtually unforeseen and disastrous consequences, and the results of others are all the same not clear. But regardless of the benefits or drawbacks of the experiments, a heightened involvement in nature and wildlife has caused many environmentalists and naturalists to vociferously oppose what they call ''meddling with nature.'' In a more philosophical and sometimes theological mood they question the role man should play in his interactions with the natural earth.
How far, for example, should mankind go to ''improve'' on nature by manipulating it and its creatures for some possible time to come benefit? Having already wreaked havoc on many forms of wild fauna, should man impose a limit on how he interferes from at present on? And is it all-time to exploit nature to relieve wildlife, or should animals be left alone to accept their normal evolutionary course without human intervention?
The Groundwork
Since man's ancestors first walked on ii legs, he has fenced in animals for food, cleared forests for crops and dammed streams to trap fish. An e'er-growing homo population, with little thought of the wild animals in its path, has extended its dominion over nature past building highways, dams and bridges, by transforming forests into farmlands and by expanding urban areas. But the plight of wildlife affected by these actions has become more than obvious and many efforts take been fabricated to salve wild creatures or improve their habitats.
Experiments accept been tried with such animals every bit bald eagles, peregrine falcons, ospreys, white-tailed deer, European boars, red wolves, black-footed ferrets, Atlantic puffins, California condors and many others.
The most ambitious of these is the Condor Recovery Programme, a multimillion-dollar project aimed at restoring a viable California condor population in the wild, which at present harbors less than xx of the huge vultures. The program involves the taking of eggs and immature condors from the nest, hatching and raising immature birds in captivity and releasing them back into the wild in the hope that they will breed and proliferate.
But the programme, run past the National Audubon Society and the United States Fish and Wildlife Service with the cooperation of the San Diego and Los Angeles Zoos, has encountered setbacks. Young condors have died, one in the nest while beingness examined past a project researcher, ii others soon later on they were hatched in captivity. The outcry over these deaths has perchance brought into sharpest focus the controversy between those who criticize such projects and those who favor them.
Those in Favor
Although many wildlife experts and scientists acknowledge that some of man's interventions in nature take been counterproductive, they feel that ''hands-on'' management of some endangered animals has been necessary or esthetically beneficial. They point to the extinction and endangerment of many animals because of ecology poisoning or hunting and habitat destruction past human, and reason that crunch management to bolster failing poulations is often necessary until the plants or animals and their ecosystems can recover and be cocky-sustaining.
David Zimmerman, author of the book, ''To Salvage a Bird in Peril,'' echoed in an interview the sentiments of many zoologists and wild animals experts when he noted: ''Species and organisms are intrinsically valuable. There is no substitute for them. They accept to be preserved.''
Advocates of easily-on wildlife management point to the many organisms whose failing populations accept been arrested or revived by manipulating them or their environments. These include bald eagles, blackness- footed ferrets, peregrine falcons, ospreys, whooping cranes, bobcats, Arabian oryxes, rare ferns and lady-slippers. And they point to environmental changes wrought by humans that are at present regarded as examples of benign and bonny topographical changes.
The tardily Rene Dubos, the microbiologist and ecologist, often cited the many man- made impacts on the earth's topography that resulted in beneficial and esthetically pleasing landscapes. He noted that in France tree- felling for fields that became fenced with hedgerows resulted in miniature wildlife sanctuaries. England's lovely downs were in one case forest which, cleared ages ago, could never grow back because sheep were pastured there. And American prairies were created by Indians who, as an aid to their autumn hunting, set fires that kept trees from ever getting started.
1 of the most articulate spokesmen for managing nature when crises ascend is Russell Peterson, president of the National Audubon Society. In an interview he said: ''Years ago nosotros wanted to let nature take its course - no captive breeding or other bogus actions. Just things got and then bad that we had to do something almost it.'' Dr. Peterson has on many occasions stated his conventionalities that because humans have created many of the weather condition that have endangered or wiped out other species, drastic means were often needed to right them, a job, he says, ''that is our responsibility.''
Those Opposed
Many of those opposed to human being'due south jockeying of wild animals say that the problem of habitat destruction should be addressed earlier wild creatures themselves are manipulated or bred in captivity. The belatedly Dr. Carl Koford, one of the world'southward experts on California condors and other wildlife, was known for his opposition to captive breeding.
''It is extremely doubtful that a condor raised by hand and lacking the experience gained by beingness raised in the wild could survive for long if released,'' he wrote later studying the California condors for several years. His opinion is seconded by several ornithologists and naturalists, amidst them David Brower, the founder and chairman of Friends of the Earth, his son, Kenneth Brower, the author and naturalist, and many members of the Sierra Club and of some Audubon Guild chapters in California.
''Man is non doing a good task of playing God,'' Mr. Brower said in an interview, ''and the evidence then far is that what he does isn't working.'' The naturalist said he felt that conservation efforts should exist full-bodied on preserving and protecting an fauna'southward habitat instead of taking birds from the wild and raising them in captivity. He added that he thought inappreciably any of the efforts to transplant or save near species were done with an understanding of the consequences that could ensue.
George Laycock, a naturalist and field editor of Audubon Magazine, made a written report of some two dozen instances of beast introductions into new habitats and establish that about of them had been failures.
In his book, ''Alien Animals,'' Mr. Laycock noted that the handsomely furred brush- tailed phalanger, commonly known as the Australian opossum, was introduced into New Zealand for its value equally a marketable fur resources. Before many years had elapsed, yet, the herbivorous marsupials, freed of the predators that controlled them in Australia, proliferated and stripped unabridged woodlands of their leaves and moved out into farms and gardens where they feasted on man's food crops. The animals were then classed as vermin and their destruction was advocated. Their population is at present minimal. Similar disasters occurred after the introduction of wild boars, mongooses, burros, rabbits, golden bother and other fauna species.
''Human being is poor at agreement the consequences of his deportment,'' Mr. Brower said, ''and he shouldn't try to rearrange what he doesn't understand. In that location is an intricate balance of life on world, and pulling pieces out and putting them somewhere else, or rearranging them, upsets the world'southward biota every bit a whole.''
The Outlook A resolution does not appear imminent. But the apparent successes with whooping cranes, eagles, ospreys, falcons, beavers, ferrets and other animals in the final few years has caused many observers to look more kindly on the manipulation of nature for the benefit of earth'south animal and human being residents.
It appears that if hands-on wildlife management programs similar the condor project are successful in increasing the wild population, more people will be in favor of manipulating animals and plants in this fashion. On the other mitt if more such programs fail, the support for intensive wildlife management will probably decrease.
And because of the failure of many of the animal resettlement efforts such equally the Australian opossum project, scientists expect that in the futurity, as recommended by both Dr. Peterson and Mr. Brower, more time and study volition be given to the possible effects of such deportment earlier they are taken.
Source: https://www.nytimes.com/1984/07/03/science/issue-and-debate-should-man-manipulate-animals.html
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