|Vol. VI, No. 1, Summer 1992 / No. 2, Fall 1992|
by James F. Keefe
|James Keefe lives in Jefferson City and was
with the Missouri Department of
Conservation for 36 years before his
retirement. He wrote
The First 50 Years, the history of the Department of Conservation, and is co-editor with Lynn Morrow of A Connecticut Yankee in the Frontier Ozarks: Selected Writing of Theodore Pease Russell. He has contributed to OzarksWatch before.
The Ozarks is one of North America's oldest land masses. Over the past 20,000 years it has under gone some remarkable changes.
During the last Ice Age it was covered by spruce-fir forest. With warming and retreat of the glaciers the deciduous hardwood forest was the dominant Ozark ecosystem. From 8,000 to 4,000 years ago the climate was much warmer and drier than now, and prairie and open grassy woodlands became the norm. Desert-adapted species of plants and animals now found in Arizona and New Mexico lived in the Ozarks. During the last 3,000 years or so the climate has been much like it is today and the plants and animals now living here became established.
These species--the survivors of European man's activities of the last 200 years---face an uncertain future. In that 200 years the forests have been massively over-cut and then re-established. Roads and farms and shopping malls have taken chunks of the forests and the threat of further alterations in the environment looms.
Essentially, wildlife exists on man's sufferance. The wildlife we have today in the Ozarks is here despite man' s activities and wouldn't exist at all if we did not act to perpetuate it. Thus, deer and wild turkey have made dramatic come-backs because we wanted them and took steps to favor their survival.
Many species have survived while others have been extirpated. We didn't consciously try to wipe out any species (except, perhaps, certain large predators and some agricultural pests), but, with settlement, and through our reckless over-cutting of the forests in the late 1800s and early 1900s, we drastically altered the habitat. Some species simply vanished, but most, somehow, managed to adjust and survive.
In the past, management of species was the role: we consciously favored certain species because they were wanted. In more recent times such management also has involved genetics, i.e., certain strains of favored species have been protected so as to assure survival under varying conditions. In the future, management will broaden its outlook and attempt to preserve bio-diversity.
Bio-diversity is the new buzz word among natural resource managers. Bio-diversity (biological diversity, of course) means the variety of living things. It exists at three fundamental levels: species diversity, genetic diversity, and community or ecosystem diversity.
Species diversity is the variety of species in an area--all the plants and animals, great and small, from soil microbes to cave crayfish to red-tailed hawks. Genetic diversity is the variability in genetic composition among individuals of the same species. It is important because it allows a species to adapt to changing environments. For example, one strain of smallmouth bass may be just slightly more tolerant of warmer water and thus able to survive when the watershed of a stream is altered. Another strain might perish. We need that genetic diversity.
An assemblage of species or populations living together makes up a community, and a group of communities, with their physical environment is called an ecosystem. Community or ecosystem diversity is the variety of communities or ecosystems within an area. The natural resource managers hope to be able to manage the Ozarks in the future to assure the perpetuation of a healthy bio-diversity. It's not going to be an easy task.
Man's activities are going to go on and resource managers must somehow attempt to care for bio-diversity in the face of this. For example, certain song bird species prefer continuous forest for nesting. The cowbird, which lays its eggs in the nests of other birds, prefers more open habitat. When we clear portions of the forest for farms and homes, we fragment the forest and make it easier for cowbirds to reach the nests of the forest dwelling species. The result is a reduction in the population of the song birds. To further complicate the problem, many of those song birds depend on tropical forests to the south during the winter, and those forests are themselves threatened.
Lake Taneycomo (in Taney County, Missouri) was drastically altered when Table Rock dam was built, because water entering Taneycomo from the bottom of Table Rock Lake was too cold to support the fish species that had lived in Lake Taneycomo. The Missouri Department of Conservation created a trout fishery where a warm-water fishery once existed to offset the lost species, but there was a considerable loss in bio-diversity in the lake. The Department of Conservation introduced a freshwater "shrimp" called gammarus into the lake to provide food for the trout, a tiny addition to the lake's bio-diversity. But populations of gammarus have declined as the area has developed and the result has been smaller trout for the angler. It is not yet known why the gammarus have declined, but there is little doubt that some changes in the lake have affected their population and those changes must have resulted from man's activities in the watershed.
Now, because of the tremendous growth in human use of, the Branson area, Lake Taneycomo is again threatened by man's activities. Construction for businesses, shopping malls, homes and roads has contributed to run-off and siltation that are having an effect on the trout population that earlier "saved" the lake for sportsmen.
Fisheries biologists have discovered that spotted, or Kentucky, bass are replacing smallmouth populations in some Ozarks streams. It isn't known for certain whether something man has done in the watershed is responsible or not. It is an example of the problems facing wildlife managers in the Ozarks, as they seek to perpetuate the smallmouth bass, and foster bio-diversity.
The wildlife that remains in the Ozarks varies in its abilities to adapt and survive future changes. Some species probably are doomed to extirpation no matter what we may do to protect them. Their demands simply cannot be met in the face of man's economic and cultural drives. What we do about all this depends on human activities but these can be altered by individual decisions and public policy. It's up to us.
The Ozarks is old and it is tough. It has endured as an ecosystem, though that ecosystem has changed many times. At least in the immediate future, with the resource managers that we have, the wildlife will endure, too.
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