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Merriam’s Turkeys (Meleagris gallopavo merriami) are associated with ponderosa pine (Pinus ponderosa) forests in the western United States, but are not native to the ponderosa pine forest of the Black Hills, South Dakota. The Black Hills population was established by transplanting birds from New Mexico and Colorado between 1948 and 1951. Despite being outside its original range, this population provides a unique opportunity to assess mechanisms of habitat selection because the age of the population is known and literature indicates that it is more productive than other populations. We...

W e studied the feeding ecology of Merriam’s turkey (Meleagris gallopavo merriami) in the Black Hills, South Dakota, between 1986 and 1989. Adult birds consumed 78 kinds of food, of which four food categories constituted >79% of winter diets and six food categories constituted >75% of summer diets. Ponderosa pine (Pinus ponderosa) seeds were the preferred winter food and birds selected habitats where pine seed abundance was highest. During drought, ponderosa pine produced fewer seeds and winter turkey diets were predominantly kinnikinnick (Arctostaphylos uva-ursi) fruits and herbaceous...

Throughout the range of Quercus macrocarpa, fire historically played an important role in maintaining Quercus stands. However, little is known about the role of fire in maintaining stringer Quercus stands on the western edge of its distribution. This research suggests that prescribed burning could be used to rejuvenate woody plants in Quercus woodlands. Relative to unburned areas, there were more (p < 0.1) Quercus, Fraxinus pennsylvanica and Acer negundo sprouts following spring burning. However, Quercus seedling density did not increase (p = 0.22) relative to unburned sites, and changes...

This paper investigates optimization approaches to simultaneously modelling habitat fragmentation and spatial correlation between patch populations. The problem is formulated with habitat connectivity affecting population means and variances, with spatial correlations accounted for in covariance calculations. Population with a pre-specifled confidence level is then maximized in nonlinear programs that define habitat patches as circles (fixed shape) or rectangles (variable shape). The ideas and model formulations are demonstrated in a case example with a maximum of four habitat patches....

As one samples species from a particular assemblage, the initial rapid rate with which new species are encountered declines with increasing effort. Nine candidate models to characterize species-accumulation functions were compared in a search for a model that consistently fit geographically extensive avian survey data from a wide range of environmental conditions. Landscape-specific species-accumulation curves generated under a bootstrap resampling plan were best described by a generalized Weibull cumulative distribution function. Traditional species-area models of cumulative species...

Many populations exhibit pronounced spatial structure: dispersed areas of high population density embedded in areas of low density, with population centers connected through dispersal. This recognition has led many conservation biologists to embrace the metapopulation concept (Levins 1970) as the appropriate paradigm for reserve design structures (reviewed in Hanski 1991 and Harrison 1994). This concept seems appropriate for those species that have patchy distributions because the critical resources on which they depend are distributed in this fashion. This paradigm may be less applicable,...

To find out if a depleted riparian system in the sagebrush steppe of eastern Oregon would respond quickly to improved management, five management treatments were applied for 7 years, ranging from ungrazed to heavily grazed treatments, including in some cases, planting of woody species. While the results varied, all treatments were too limited to significantly restore the damaged areas within the 7-year span. Although some improvements were made in woody plant densities, little meaningful change occurred in the frequencies of herbaceous wetland plants, densities of small wildlife, or stream...

An important research area regarding the wild turkey (Meleagris gallopavo) is development of sound habitat models. Habitat models provide standardized methods to quantify wild turkey habitat and stimulate new research hypotheses. Habitat suitability index (HSI) models show species-habitat relationships on a scale of O-l, with 1 being optimum. A proposed HSI model for Merriam’s turkeys (M. g. merriami) was applied to data we collected at Merriam’s turkey locations and random sites in the Black Hills, South Dakota. We tested this model, assuming that if all available habitats were suitable...

This international symposium on theory and techniques for assessing the accuracy of spatial data and spatial analyses included more than ninety presentations by representatives from government, academic, and private institutions in over twenty countries throughout the world. To encourage interactions across disciplines, presentations in the general subject areas of spatial statistics, geographic information systems, remote sensing, and multidisciplinary approaches were intermixed throughout the three days of sessions.Individual papers from this publication

Growing concern over sustainability of central ldaho forests has created a need to assess the health of forest stands on a relative basis. A stand hazard rating was developed as a composite of 11 individual ratings to compare the health hazards of different stands. The composite rating includes Douglas-fir beetle, mountain pine beetle, western pine beetle, spruce beetle, Douglas-fir tussock moth, western spruce budworm, dwarf mistletoes, annosus root disease, Swhweinitzii root and butt rot, and wildfire. The interacting effects of these agents were also considered.