Biologists have a term called ecosystem services; it refers to tangibles such as pure air, clean water, intact soils, and healthy plant communities that are derived from healthy complex ecosystems. Species, including humans, benefit from free ecosystem services. Until now, ecosystem services were not given a monetary value; instead, we humans took these services for granted—putting short-term economic gain over the value of plants, animals, and water.
That value system has now changed. According to today’s New York Times in a piece called “Maybe only God can make a tree, but only people can put a price on it,” New York City has assessed the monetary value of trees, not for their lumber, but for their ecosystem services.
Native carnivores too should be given a monetary value. We know that top carnivores such as coyotes, wolves, and mountain lions provide unique ecosystem services. Carnivores contribute to ecosystem health and functionality—their effects cascade through all the trophic layers as these three examples provide:
- Since 1995, wolves have indirectly brought free-flowing above-ground water in Yellowstone and thus created habitat for more species. After the wolf reintroduction into the Park more than a decade ago, elk, which had decimated willow and aspen stands, were forced to be more mobile to avoid predation. With less elk herbivory, willow communities returned, beavers followed and used trees and shrubs to build their dams and lodges. Those structures not only brought water from underground to the surface, but made water flow more dependable. As a result, neotropical and water-wading birds and moose populations increased (Smith et al. 2003).
- A new study indicates that the presence of pumas in desert ecosystems can have the same top-down effects resulting in increased biological diversity and functionality of rare riparian systems (Ripple and Beschta 2006).
- Coyotes regulate mesopredators (that is, medium-sized carnivores such as skunks and raccoons) and thus more ground-nesting birds survive (Crooks and Soule 1999) and rodent species diversity is more robust (Henke and Bryant 1999).
In short, carnivores increase both the richness and complexity of animal life and indirectly contribute to better ecosystem function. Despite this important free work, the federal government and others spend literally hundreds of millions of dollars annually in attempts to eradicate or scale back predator populations. Not only can this imperil native species and destabilize ecosystems, it has resulted in unintended consequences with generalists such as coyotes, which have increased their range several fold.
Now, if we can only get federal governmental agencies such as the Forest Service, the Bureau of Land Management, Wildlife Services, and the Geological Survey to assess ecosystem services, we might be living in a world that is more balanced and healthier for all.
By Wendy Keefover-Ring, Director, Carnivore Protection Program, Sinapu