By Glenda S. Booth
Photos by Spike Knuth/DWR
In the 1970s, the threatened extinction of a 3½-inch-long fish called a snail darter almost derailed Tennessee’s Tellico Dam. The furor, an epic battle that went to the U.S. Supreme Court, provoked heated debates about the value of the federal Endangered Species Act and questions like, “Why care about a snail darter?” Battles over little-known endangered species have periodically erupted since the federal Endangered Species Act (ESA) became law in 1973.
To some people, it may seem unimportant to lose an obscure bug or rodent. The goal of the ESA is to protect both imperiled species and the ecosystems they need to survive and recover. Some extinctions naturally occur, but today’s rate of extinction is higher than the natural rate, largely because of human activity, experts say.
Ecosystems are composed of many individual species. All species have a niche and a role in the environment, and as wildlife ecologist Aldo Leopold wrote, “If the land mechanism as a whole is good, then every part is good, whether we understand it or not . . . To keep every cog and wheel is the first precaution of intelligent tinkering.”
A balanced and healthy ecosystem depends on the interactions of species in the web of life. Because of this interdependence, the loss of one species can trigger the loss of another. The loss of one species can unravel an entire ecosystem, like pulling out the threads of a sweater. “When you try to pick out anything by itself, we find it hitched to everything else in the universe,” wrote conservationist John Muir.
The addition or loss of a top predator can lead to what scientists called a “tropic cascade.” The eradication of wolves in eastern North America contributed to larger white-tailed deer populations, many contend. The loss of pollinators could bring a decline in seed and fruit production.
“All these species, whether big or small, are essential elements of ecosystems,” Lauren McCain, senior federal lands policy analyst at the nonprofit Defenders of Wildlife, has written. “When they are lost or depleted, nature’s careful balance is disrupted. We cannot bring back the passenger pigeon or the Carolina parakeet and other extinct species, but we have the power to save the endangered species that remain and restore the biodiversity fundamental to our own well-being.” In short, we should be concerned about not only individual species, but also the loss of function and niches up and down the hierarchical scale, the overall biodiversity.
Some argue for saving species in terms of their importance to people. Many medicines come from plant sources, like penicillin from Penicillium mold. Some plants and animals feed the world. Some people offer an economic rationale, such as pointing out that leveling forests can increase stormwater pollution and flooding.
“Why should we need to point to some known exceptional value of a species to humans for it to be worth saving?” asked Jason Bulluck, Virginia’s Natural Heritage Program Director, Department of Conservation and Recreation. “All species fill some ecological niche, have a purpose, or provide services to other species and have a place in nature and in the natural heritage of the Commonwealth. So, why would we consider it ‘okay’ for any species to be removed, whether we think we fully understand its values or not?”
Every creature has intrinsic value. Our natural assets are our life support system. Their impairment or disappearance can ultimately threaten the human race. “Conservation of our resources is the fundamental question before this nation, and… our first and greatest task is to set our house in order and begin to live within our means,” President Theodore Roosevelt warned in a 1909 message to the U.S. Congress. That message is even more compelling today.