Treesearch

Biodiversity loss is one of the most severe global environmental problems. Among other factors, it is fostered by the destruction and fragmentation of natural ecosystems. The Chihuahuan prairies merit no exception; a great number of its associated species are endangered by habitat fragmentation or deterioration. The prairie dog (Cynomys spp) illustrates this situation. Prairie dogs are rodents that form extensive colonies in northwest Mexico. Historically this species occupied extensive grassland areas. However, its current geographic distribution is only 2 percent of its original range....

Today, rural communities need to take a new approach to decision-making and administration with regards to the causes and solutions to the processes of land deterioration. If the damages caused by drought, flood, and erosion were valued in monetary terms, opportunity costs, and value of human life, we would readily realize the benefits of investment in rural production methods.

We would have liked to hear more talks about production issues and alternative modes of production, such as the one given about ecotourism activities. However, the examples and experiences from Sonora and the United States were very useful and interesting. In a subsequent meeting, we would like to hear more about legal and organizational issues and not so much about research.

The Sonoran Institute (SI) is a non-profit organization working with people toward common conservation goals. Two objectives guide the work of the Sonoran Institute in the Santa Cruz River Region in Sonora, Mexico: to establish projects with community participation that can result in tangible and long-lasting benefits to the environment, and to ensure success by developing projects that engage communities in activities beneficial to the community and the environment. The Institute understands that landowners participate more actively in conservation when projects address critical needs.

Domestic farm and ranch properties use a variety of water retention structures and water supply infrastructures that benefit wildlife. Some water supply systems, however, are harmful to wild birds, small mammals, and reptiles. Water supply systems include metal water tanks, cemented reservoirs, or excavated earthen retention ponds (or tanques as they are known in northern Mexico and the southwestern United States). Wildlife may drown in water tanks, when drinking, bathing or catching previously trapped animals. This problem is more common in arid and semiarid areas, where natural water...

The main goal of grassland rehabilitation is to reestablish vegetation, with the objectives of reducing soil erosion, incorporating more rainwater into the soil and aquifer, maintaining biodiversity, restoring scenic beauty, and attaining a site's forage potential, as well as maintaining and reproducing the native fauna. Pastures can be rehabilitated naturally by balancing animal numbers with appropriate grassland area and distributing animals appropriately, by resting and rotating pastures, and by controlling invasive shrubs and toxic plants. Areas can be rehabilitated artificially by...

A result of rapid growth in human population and energy use, is proliferating power lines that electrocute birds, killing eagles and causing power outages. The United States was one of the first countries to recognize the significance of this problem. Suggested Practices for the Protection of Raptors on Power Lines, first published in the 1970s, has now been translated into Spanish; it discusses biological aspects of raptor electrocution, and explains which electric structures are dangerous and how they can be modified to prevent electrocutions. In the United States, however, the plethora...

The objectives of this presentation are to: (1) describe how ecotourism differs from traditional tourism; (2) provide examples of ecotourism from the U.S.-Mexico region; and (3) suggest potential ecotourism development in the Casas Grandes area; and (4) describe potential problems related to such development. My background in ecotourism is related to two projects: (a) a $200,000 countywide ecotourism development project I helped initiate and manage in Oregon (Forbes 1998); and (b) my dissertation on conservationist Aldo Leopold’s 1930s visits to Municipio Casas Grandes and how ecotourism...

Many ecologists have indicated that fire is as important as wind or precipitation in shaping North American ecosystems. There is little question that fire is prevalent in grasslands and that it contributes to the structure and function of such systems in the Southwest. In this paper I outline pre-settlement fire regimes, then describe post-settlement regimes and vegetation response to fire. I conclude by describing the potential for applying fire to these systems, many of which have not experienced fire for many years. This overview draws heavily from Wright and Bailey (1982) and McPherson...

I'd like to talk a little bit about another important disturbance regime in much of the western United States and Mexico. We've talked some about the importance of fire. Another one is the importance of natural hydrological cycles. But an often-overlooked important ecological disturbance regime is predation. Research around the world and in many habitats has found the importance of large carnivores in top-down regulation of ecosystems.