Wild Again. David S. Jachowski
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Around the same time, Michael Soulé and Brian Wilcox convened the First International Congress on Conservation Biology in 1978 in San Diego. Although the concept of conserving species had been around for decades in the United States, and for centuries in Germany and India, never before had ecologists taken such a proactive stance toward the protection of the natural world. They took a step away from hard lines of experimental science and reasoning toward a field that blurred the lines between advocacy and the more traditional scientific objectivism. As Soulé and Wilcox would later define the field, “Conservation biology is a mission-oriented discipline comprising both pure and applied science.” It blended traditional biological and ecological sciences with economics, sociology, and education, all in an effort to preserve species in the face of human persecution that was happening at local and global scales.
The urgency of the field was unique, controversially setting a framework within which scientists could enter into the realm of management for the sake of protecting what they study. As tropical ecologist Daniel Janzen would later advocate, “If biologists want a tropics in which to biologize, they are going to have to buy it with care, energy, effort, strategy, tactics, time and cash. . . . If our generation does not do it, it won’t be there for the next. Feel uneasy? You had better. There are no bad guys in the next village. They is us.” Scientists could no longer take the high road and claim that extinction is a natural process, part of Darwinian evolution, and move on to studying the next biological phenomenon.
For a discipline that emphasizes the conservation of biological diversity (the term biodiversity would not be adopted until 1988), extinction was the dirtiest of words. Many of those attending the San Diego meeting had worked on island systems or were still focusing their thoughts on the theory of island biogeography that had been developed by Robert MacArthur and E.O. Wilson a decade earlier. The influential theory was that the risk of extinction for a species on an island is a function of the size of the island and its isolation from other suitable islands. There was a corresponding belief that on the mainland, habitat fragmentation (in which humans removed habitat and further divided the landscape) similarly affected species. If we isolate a species on one of these virtual islands, such as a patch of forest surrounded by corn fields, the probability of that species going extinct increases. The smaller the patch, the worse off a species would be.
To avoid losing these “island” populations and risking extinction, ecologists began trying to identify critical population sizes to avoid extirpation. Mathematical models were developed for an individual species or population that, in their simplest form, were projections of the population into the future based on historical rates of births and deaths. But there was a need to account for a number of obstacles that could make small populations prone to extinction. Small populations within an island of habitat are more vulnerable to unpredictable events like floods or catastrophic fires.
For his dissertation research in 1978, Mark Shaffer developed a formula for predicting the minimum population size of grizzly bears to withstand such unpredictable events, which he termed the “minimum viable population size” (MVP). Over time, others would add to the complexity of such MVP models by including long-term detrimental effects like decreased reproductive output as a result of inbreeding and other factors. The product was hard numbers that could be used by wildlife managers to outline how many animals they needed to maintain, similar to agricultural balance sheets used by cattle ranchers to balance predicted losses against predicted gains, trying to stay in the black. But more than that, by experimenting with the numbers in the model, scientists could begin to say what factors needed to improve to keep the species viable. How would the population respond to a year of good rain that would perhaps result in a sudden 30 percent increase in juvenile survival? What would happen if we stopped a hunting season and were able to decrease adult mortality by 10 percent? These were hard numbers rather than sentiments to bring to politicians and the public when trying to maintain or recover a species.
The risk of species loss and the value in conserving rare populations also were brought to the forefront of public policy. The Endangered Species Act of 1973 (built on the backs of previous acts of 1966 and 1969) was amended to require not only listing of threatened and endangered species, but also designation of critical habitats and development of population recovery plans for those listed species. The National Forest Management Act of 1976 required the U.S. Forest Service to “provide for diversity of plant and animal communities based on the suitability and capability of the specific land area.” In effect, this made national forest managers responsible for maintaining viable populations of native species in their planning areas. Given that endangered and threatened species were typically most at risk of loss, the emphasis was put largely on maintaining or increasing their small populations.
The theoretical and political pieces were coming into place for the conservation of black-footed ferrets, should they ever be rediscovered and brought back from extinction.
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On the morning of September 26, 1981, John and Lucille Hogg were having breakfast in their ranch home, an unassuming white-painted house in the center of a moderately sized ranch in the open, rolling hills and sagebrush flats west of Meeteetse, Wyoming. Up and down the valley the bustle of summer had ended. The rush of growing, irrigating, and cutting hay for the winter had given way to winter preparation. The cows and their calves were coming back into the corrals on homesteads and off the federally leased summer range. Daily chores switched from fences and farming to feeding livestock and preparing for the calving season, assessing the summer’s alfalfa hay crop, and calculating whether there was a need to buy hay to make it through the winter.
The ears of a sleeping rancher must be finely tuned to the sounds of the outdoors, keen to the sound of a bawling cow in early labor, even through the walls of a house in the middle of the night. Lucille Hogg hadn’t slept well because their Australian cattle dog, Shep, was barking and growling outside in the middle of the night. Lucille tossed in bed, settling on the thought that the dog was just learning another lesson on why to steer clear of porcupines. Knowing that there was little she could do in the middle of the night to pull out the hooklike barbs, she decided it could be dealt with in the morning, so she fell back asleep.
Over breakfast, Lucille told John to check Shep for porcupine quills and inspect the damage before the quills corkscrewed too deep into his muzzle and a trip to the vet was in order. Stepping out the front door, John noticed Shep was intact and uninjured, ready for the day. On the front stoop he’d left a carcass, the likely victim of his nighttime ruckus left for show to his owners. As John peered down at the thin carcass, his first reaction was that he had no clue what Shep had dispatched. It was a buff-brown animal with black markings on its paws, face, and tail. Perhaps it was an oddly marked pine marten that had come