Treesearch

This chapter addresses the large native ungulates (American bison (Bos bison), elk (Cervus elaphus), white-tailed deer (Odocoileus virginianus), mule deer (Odocoileus hemionus), and pronghorn (Antilocapra americana) of the grasslands. The information presented includes historical background, description of the species’ biology and ecology, and management in relation to domestic animals.

We used fixed-wing aircraft to survey the entire shoreline and connecting channels of the five Great Lakes to determine potential nesting habitat for bald eagles (Haliaeetus leucocephalus) during 1992. Habitat was classified as either good, marginal, or unsuitable, based on six habitat attributes: (a) tree cover, (b) proximity and (c) type/amount of human disturbance, (d) potential foraging habitat/shoreline irregularity, and suitable trees for (e) perching and (f) nesting. Of the 10,596 km of shoreline surveyed, we classified 7,006 km (66%) as potentially suitable (i.e. either good or...

Efforts to regenerate oaks on California’s oak woodlands often must address how to establish seedlings in areas grazed by livestock. Research indicates that damage to young oak seedlings from cattle varies by season, with less damage during the winter when deciduous oaks do not have leaves. While exclusion of cattle from planted areas does result in reduced damage, the buildup of thatch or dead grass following livestock removal can promote an increase in damage to seedlings from voles (Microtus californicus) and grasshoppers (Melanoplus devastator). The most effective method we have found...

Range managers in the Southwestern States are increasingly being required to develop management strategies that take into consideration the conservation of wildlife populations. However, information on many aspects of the fundamental biology and impacts of grazing on individual species is still lacking in the scientific and government literature. This report documents a project designed to assemble this information for terrestrial wildlife in Arizona and New Mexico that have the potential to be negatively impacted by grazing or range management practices. To achieve this, a two-stage panel...

Grasslands in the Apache Highlands ecoregion have experienced dramatic changes. To assess and identify remaining native grasslands for conservation planning and management, we used a combination of expert consultation and field verification. Over two-thirds of native grasslands have experienced shrub encroachment. More than 30% of these may be restorable with prescribed fire. Private land accounts for more than half of open, non-shrub invaded native grasslands. Almost 95% of the private lands in this study have no legal protection. Over 25% of all native grasslands are contained in the...

A wildfire in the Chiricahua Mountains of southeastern Arizona apparently altered the long-term structure of the forest. The pre-fire canopy forest, which had not burned for 100 years, was an even mixture of Arizona pines and Rocky Mountain Douglas-firs. A decade later the new forest was numerically dominated by quaking aspen seedlings in clumps separated by persistent gaps. Douglas-firs were positively associated with aspens but Arizona pines were not. The new forest was more open, diverse, and patchy than the one it replaced. Extensive stand-replacing fires in the Mountain West may...

We summarized existing knowledge on winter movements and range and habitat use of radio-marked Mexican spotted owls. In light of that information, we evaluated the adequacy of current management guidelines. Seasonal movement or "migration" appears to be a regular feature of the winter ecology of Mexican spotted owls. Most radio-marked owls studied were resident in and around their breeding areas year-round, but some owls migrated in most populations studied. Owls that were year-round residents generally expanded their home range during the non-breeding season, and many exhibited spatial...

The demand for strategic planning tools that account for climate and human influences on wildfire hazard is growing. In response, the University of Arizona, through an EPA STAR Grant has undertaken interdisciplinary research to characterize the human and climate dimensions of wildfire. The resulting Fire-Climate-Society (FCS-1) prototype model developed for Sky Islands in southeastern Arizona (Catalina/Rincons, Huachucas, Chiricahuas) addresses both the biophysical elements of wildfire probability and the human elements of values-at-risk. An online, spatially explicit application will...

One of the most important issues facing resource managers today is that of information. In order to handle the numerous and diverse requirements for information, landscape-scale information management systems are needed that allow individual land management units to view their resource information in a regional context. The characteristics of such a system are: (1) the storage of basic data sets and GIS layers, (2) the development of Internet software tools and protocols to facilitate data sharing, (3) personnel to operate and maintain the system, and (4) system coordination and training...

FFE-FVS is a model linking stand development, fuel dynamics, fire behavior and fire effects. It allows comparison of mid- to long-term effects of management alternatives including harvest, mechanical fuel treatment, prescribed fire, salvage, and no action. This fact sheet identifies the intended users and uses, required inputs, what the model does, and tells the user how to obtain the model.Other publications in this series