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The Importance of Maintaining Carnivores in Wildlands (transcription) Dave Foreman The Wildlands Project I’d like to talk a little bit about another important dis- After the coyotes were trapped out, kangaroo rats were turbance regime in much of the western United States able to outcompete the other five species of burrowing and Mexico. We’ve talked some about the importance rodents. This displacement is called competitive exclu- of fire. Another one is the importance of natural hy- sion. Without the predation pressure of the coyotes on drological cycles. But an often-overlooked important the kangaroo rats, the other species could not compete ecological disturbance regime is predation. Research with the kangaroo rats. around the world and in many habitats has found the Those are just a few examples from around the world importance of large carnivores in top-down regulation of the importance of top-down regulation of ecosystems of ecosystems. by large carnivores, how these ecosystems begin to un- Jim Estes, studying sea otters off the coast of ravel when large carnivores are removed, and how these California some 20 years ago, found that when the sea ecosystems begin to regain integrity when the large otters had been trapped out over 100 years ago, their carnivores are reintroduced. habitat, the kelp forest, often called “the redwood forest Another importance of large carnivores for conser- of the Pacific Ocean,” disappeared. The reason for this vation is their umbrella effect. If you protect habitat was that, without the sea otter to control the sea urchin, adequate for a viable population of large carnivores, sea urchin populations exploded and grazed away the you are going to protect habitat for many other species kelp forest, losing not only the kelp forest but also the as well, certainly not for all species, but for many. And many other species dependent on it. Since California sea a final important reason for protecting large carnivores otters have been reintroduced in the Pacific Ocean, the is their effect on our behavior and on our attitudes. If kelp forest and other species have been coming back. there is anything human beings have too much of, it’s Yellowstone National Park lost all wolves and moun- arrogance. There is nothing quite like large carnivores tain lions in 1930. The park service trapped and shot to teach us humility. them out. Elk populations in Yellowstone National Park I’d like to show how the Wildlands Project and other grew very large. But even more importantly, elk behavior groups such as Sky Island Alliance and Naturalia are us- changed. The elk became lazy, lying in large herds in the ing these ideas of top-down regulation and conservation meadows near the rivers, chewing their cuds, overgrazing. in this area on the U.S.–Mexico borderlands that we call The area looked like one of the worst cow pastures around the Sky Islands, the area that is the overlap between the in some places. So bad was the elk overgrazing and over- Rocky Mountains and the Sierra Madre, between the browsing that beavers could not reestablish themselves in Sonoran Desert and the Chihuahuan Desert. Michael Yellowstone National Park—the elk had browsed away Soule and Reed Moss, two of the leading conservation the willows. But when wolves were reintroduced into biologists in the world, propose a scientific conservation Yellowstone less than ten years ago, suddenly the elk approach called “rewilding.” Based on the important role behavior changed radically. They were no longer big, of large carnivores in regulating ecosystems and on the fat, lazy “meadow potatoes.” They were elk again. They need of large carnivores for large, secure habitat areas were up running around, looking over their shoulders at and the fact that in much of the world today there are no the wolves. While the wolves have not caused the elk longer large-enough single protected areas, “rewilding” population to decrease, they have radically changed elk means we have to look at landscape linkages, or connec- behavior. Now the overgrazed meadows are coming back. tivity, between protected areas and other habitat. Willows are growing back up in streams and researchers Requirements for survival represent factors important believe that beavers are going to be able to recolonize to maintaining ecological health. Among these focal spe- streams in Yellowstone National Park. cies are keystone species. Keystone species, like large The last example I want to give occurred in west carnivores, have a disproportionate effect on the ecosys- Texas where coyotes had been experimentally trapped tem and other species relative to their actual numbers. out of an area that had six species of burrowing rodents. Here in the Sky Islands region (Figure 1), the Mexican USDA Forest Service Proceedings RMRS-P-40. 2006. 35 The Sky Islands Wildlands Network: A proposed system of conservation lands. A Network: The Sky Islands Wildlands Figure 1. 36 USDA Forest Service Proceedings RMRS-P-40. 2006. wolf was probably the most important keystone species. some of these dirt roads be closed to provide a larger The loss of the Mexican wolf has caused changes in the secure area. landscape. Recently Mexican wolves have been reintro- The Gila and the Aldo Leopold wilderness areas are duced in southeastern Arizona and southwestern New highly isolated. They are island protected areas and are Mexico. Carnivores like the Mexican wolf and the jaguar not connected to one another. We know that many species need large core areas and connectivity because they are need landscape linkage; they need to move across large vulnerable to persecution. The authors of Continental areas. This ecosystem connectivity maintains ecosystem Conservation, the state-of-the-art book on science-based flows. It is essential for the population viability of wide- conservation, say that protected areas should be roadless ranging species and it also enhances wilderness. Instead or have limited access. This was shown with the rein- of the old model of isolated national parks, wildlife troduction of Mexican wolves in the Apache-Sitgreaves refuges or other protected areas, Reed Noss and oth- National Forests. Large core areas can allow for more ers have proposed a new model where we look at the species, maintain natural disturbance regimes like fire, entire landscape, where we look at protected core areas, ensure population viability of sensitive species and en- wildlife movement linkages between them, and also at hance wilderness. compatible-use areas on private and public land around The Mexican wolves were originally released in an area these protected areas, to look at the landscape as a whole of the Apache National Forest in Arizona that had many dirt and not only for conservation purposes, but also for how roads through it. Almost immediately five were shot along- people can sustainably make a living on the landscape side dirt roads. Two others were run over. What needed to outside the core protected areas. be done was to have reintroduced the Mexican wolf in the We have been finding that to connect areas in Arizona Gila wilderness area and the Aldo Leopold wilderness area and New Mexico, looking at public lands is not enough. in New Mexico, almost a million acres of roadless country, We have to look at well-managed private lands such as much of it ungrazed by domestic livestock. The Mexican Guadalupe Canyon Ranch, owned by my friend Drum wolf and other large carnivores need these roadless pro- Hadley, and other large ranches owned by members of tected areas if they are going to survive. the Malpais Borderlands group, not to tell the landowners The jaguar once ranged throughout New Mexico, what to do with their land, but to acknowledge their ex- Arizona, Texas, Louisiana, and Arkansas in the United emplary management and to examine how their ranches States. It is one of the focal species in the Sky Islands and their grazing practices fit into larger conservation Wildlands Network, and conservationists in the United objectives. So instead of isolated protected areas, we have States and Mexico are studying how we can get jaguar proposed a system of public and private lands to be man- populations to disperse back into Arizona and New aged as a whole, to try to put linkages back into landscape Mexico. So we have developed a recommendation for the so that jaguars can disperse north into the United States jaguar as a focal species, conservation recommendations and that ultimately Mexican wolves can disperse south to help jaguars disperse from their northernmost breeding into Sonora and Chihuahua as well (Figure 1). I think that population in Sonora and begin to recolonize suitable all of us, landowners, ranchers, conservationists, hunt- areas in Arizona and New Mexico. Jaguar researchers ers and wildlife biologists are all interested and all need tell us, for example, that among the preferred areas for to work out an approach to the entire landscape so that jaguars in the United States are lower elevation river healthy communities, healthy families can coexist with regions, such as the Blue River in southeastern Arizona. healthy families and communities of jaguars, thick-billed This area has a jeep trail through it, a dirt road through parrots, Mexican wolves, prairie dogs and many other it. For jaguars’ security, conservationists, with some species, so that we truly can create conservation-oriented support from a few local ranchers, are proposing that and sustainable land use for the 21st century. USDA Forest Service Proceedings RMRS-P-40. 2006. 37 La Importancia de Mantener Carnívoros en Áreas Silvestres (resumen) Dave Foreman Proyecto Wildlands Según han demostrado estudios realizados alrededor y seguras, y en la conectividad entre áreas protegidas y del mundo, los carnívoros de gran tamaño regulan los otros hábitats.

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