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Articles 1261 - 1290 of 1588

Full-Text Articles in Ecology and Evolutionary Biology

Preliminary Testing Of A Selenium-Based Systemic Deer Browse Repellent, T. R. Angradi, W. M. Tzilkowski Oct 1987

Preliminary Testing Of A Selenium-Based Systemic Deer Browse Repellent, T. R. Angradi, W. M. Tzilkowski

Wildlife Damage Management Conference

Silviculturists use a variety of techniques, including repellents, to reduce browse damage by white-tailed deer (Odocoileus virginianus) to valuable eastern hardwood seedlings. Systemic selenium, sodium selenite, was evaluated with captive white-tailed deer for its repellency in white ash (Fraxinus americana) and black cherry (Prunus serotina) seedlings. Selenium had no effect in reducing browsing of black cherry. However, there was a reduction (p < 0.05) in the white ash browsing level.


Effects Of Differential Pine Vole Populations On Growth And Yield Of "Mcintosh" Apple Trees, M. E. Richmond, C. G. Forshey, L. A. Mahaffy, P. N. Miller Oct 1987

Effects Of Differential Pine Vole Populations On Growth And Yield Of "Mcintosh" Apple Trees, M. E. Richmond, C. G. Forshey, L. A. Mahaffy, P. N. Miller

Wildlife Damage Management Conference

Pine voles (Microtus pinetorum LeConte) were maintained as known populations (0, 269, 538 and 1075/ha) in wire mesh-enclosed blocks of 'McIntosh'/M26 apple trees (Malus domestica Borkh.) for 2 years. There was little measurable effect of the voles on growth and production the 1st year, but during the 2nd year the highest population was associated with the death of one tree; severe reductions in growth, yield, and fruit size; a 78% reduction in crown bark weight, 56% loss of fibrous roots, and a dramatic reduction in the value of the crop. Although the low and the medium populations showed …


Nonpredatory Mammal Damage Research Needs, John L. Seubert Oct 1987

Nonpredatory Mammal Damage Research Needs, John L. Seubert

Wildlife Damage Management Conference

Nonpredatory mammal damage probably exceeds one-half billion dollars each year in the U.S., in spite of many techniques and programs for controlling such losses. Improved and new control methods are obviously needed. The task of ADC researchers has become increasingly demanding and complex, however. They must not only obtain information to satisfy recurring Environmental Protection Agency (EPA) data call-ins required to maintain and improve existing State and Federal rodenticide registrations, but must develop and register new damage control techniques and strategies. New methods must be highly efficacious, safe, cost effective, and present the lowest possible hazard to nontarget species and …


Avoiding Controversies That Impede Wildlife Damage Control, B. W. O'Gara Oct 1987

Avoiding Controversies That Impede Wildlife Damage Control, B. W. O'Gara

Wildlife Damage Management Conference

Controversies regarding wildlife damage control often result from incorrect perceptions by the general public or conservation groups. Such controversies can usually be settled to most people's satisfaction by indisputable data. In the past, however, data were often lacking. The ban, by Executive order in 1972, of chemical toxicants for predator control on federal lands and by federal agencies is a good case in point. Indisputable data were not available concerning the level of predation. The only data were derived from questionnaires filled out by livestock producers; Government officials and the public simply would not accept such data as unbiased.


Research Needs In Wildlife Damage Control: Research Needs As Perceived By State Directors In The Eastern Adc Region, Dennis Slate Oct 1987

Research Needs In Wildlife Damage Control: Research Needs As Perceived By State Directors In The Eastern Adc Region, Dennis Slate

Wildlife Damage Management Conference

This presentation provides a brief overview of wildlife damage-related research needs as they are perceived by Animal and Plant Health Inspection Service (APHIS), Animal Damage Control (ADC) State Directors in the Eastern ADC Region. There are 23 State Directors in the Eastern ADC Region who are responsible for managing operational and technical assistance animal damage programs in 31 states. Because of their collective experience with a variety of species and control techniques under various environmental circumstances, their imput and insight should be valuable in helping those in the research community more clearly define wildlife damage-related research needs.


Decontamination Of A Histoplasma Capsulatum-Infested Blackbird Roost: Use Of A Sprinkler System To Apply Formalin, A. R. Stickley Jr., J. R. Pruitt, C. E. Hume, T. Pass Ii, C. H. Gayle Oct 1987

Decontamination Of A Histoplasma Capsulatum-Infested Blackbird Roost: Use Of A Sprinkler System To Apply Formalin, A. R. Stickley Jr., J. R. Pruitt, C. E. Hume, T. Pass Ii, C. H. Gayle

Wildlife Damage Management Conference

When disturbed, blackbird/starling roost sites can be sources of locally severe outbreaks of histoplasmosis; therefore decontamination with formalin is sometimes prudent. We describe the use of a $5000 sprinkler system for spraying formalin on a Histoplasma capsulatum-infested roost site. This system precludes direct worker involvement in the application of this hazardous chemical to the area. Analysis of soil samples collected and cultured both before and after formalin treatment confirmed the eradication of H. capsulatum from the 1.3 ha site. Cost was approximately $17,000 with sprinkler system provided at no charge.


Clonal Foraging In Perennial Wheatgrasses: A Strategy For Exploiting Patchy Soil Nutrients, L. D. Humphrey, D. A. Pyke Oct 1987

Clonal Foraging In Perennial Wheatgrasses: A Strategy For Exploiting Patchy Soil Nutrients, L. D. Humphrey, D. A. Pyke

Aspen Bibliography

1 Foraging by means of plasticity in placement of tillers in response to low- and high- nutrient patches was examined in the rhizomatous wheatgrass Elymus lanceolatus ssp. lanceolatus. Its ability to exploit soil nutrient patches was compared to that of the closely related but caespitose E. lanceolatus ssp. wawawaiensis. 2 Clones of 14 genets of each taxon were planted in boxes consisting of two 30 x 30 cm cells: the 'origin cell' where clones were planted, and the adjacent 'destination cell', with each cell containing soil with either low or high levels of nutrients. 3 The rhizomatous taxon, which can …


Extension's Perspective Of Federal, State And Private Animal Damage Control Programs, Gary J. San Julian Sep 1987

Extension's Perspective Of Federal, State And Private Animal Damage Control Programs, Gary J. San Julian

Wildlife Damage Management Conference

Extension personnel are in a unique position to observe and to be involved in animal damage control (ADC) programs at the federal, state and private levels. In order to offer educational programs, we must interpret regulations and policies to provide a workable interface between ourselves, other agencies and the public. This is not an easy task in such a sensitive and emotional area.


Disturbed Alpine Ecosystems: Seedling Establishment Of Early And Late Seral Dominant Species, Jeanne C. Chambers May 1987

Disturbed Alpine Ecosystems: Seedling Establishment Of Early And Late Seral Dominant Species, Jeanne C. Chambers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the effects of seedbed and seedling environment on establishment of early and late seral dominant alpine species. Species studied included late seral dominant forbs (Geum rossii, Artemisia scopulorum, and Polemonium viscosum), early seral dominant forbs (Potentilla diversifolia and Sibbaldia procumbens), a late seral dominant grass (Festuca idahoensis), and early seral dominant grasses (Calamagrostis purpurascens and Deschampsia cespitosa). Germination responses of each species to wet vs. dry cold stratification and light vs. dark conditions were investigated. No statistical differences were observed in the seed germination of early and late …


Autecological And Grazing Control Studies Of Dyers Woad (Isatis Tinctoria L.) On Northern Utah Rangelands, Kassim O. Farah May 1987

Autecological And Grazing Control Studies Of Dyers Woad (Isatis Tinctoria L.) On Northern Utah Rangelands, Kassim O. Farah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dyers woad (Isatis tinctoria L.) is a noxious weed on northern Utah rangelands. Chemical and mechanical means of control are unsuitable for rangelands. A potential alternative, biological control, is difficult due to a lack of basic ecological information. To remedy this, some aspects of the population biology and autecolgy of dyers woad were studied. The feasibility of controlling dyers woad by early spring grazing was also investigated via clipping experiments.

A population study followed the survivorship of experimentally established populations over two years. Fall germinating individuals (1984) overwintered as rosettes twice and all survivors reproduced successfully. Spring germinating individuals …


Factors Affecting The Sprouting Response Of Woody Caatinga Species And Their Implications For Improved Caatinga Management, Linda Howell Hardesty May 1987

Factors Affecting The Sprouting Response Of Woody Caatinga Species And Their Implications For Improved Caatinga Management, Linda Howell Hardesty

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In northeast Brazil grazing is a major use of much of the semiarid woodlands (caatinga). Animal production is limited by lack of dry season forage, primarily deciduous tree leaves. Management is constrained by the persistence of undesirable trees that sprout from the stump (coppice). This study evaluates the possibility of manipulating coppicing trees to improve caatinga management, particularly dry season forage production.

The season of cutting can influence coppicing. Trees were cut early and late in the wet and dry seasons. After two years, trees of all species cut in the late wet season produced less biomass than those cut …


Causes Of Seeding Failure Within The Tooele Fire Rehabilitation Project In Northwestern Utah, Jeffrey S. Murphy May 1987

Causes Of Seeding Failure Within The Tooele Fire Rehabilitation Project In Northwestern Utah, Jeffrey S. Murphy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The original purpose of this study was to examine the influences of ecological site, seeding method and planting season on rangeland seeding success within the Tooele Fire Rehabilitation Project (TFRP) in northwestern Utah. The major objective of the TFRP, designed by the USDI Bureau of Land Management, was to establish a permanent cover of 'Nordan' crested wheatgrass (Aqropyron desertorum (Fischer ex Link) Schultes), 'Luna' pubescent wheat grass (Thinopyrum intermedium ssp. barbulatum (Schur) Barkw. and D. R. Dewey) and 'Alkar' tall wheatqrass (Thinopyrum ponticum (Podp.) Barkw. and D. R. Dewey) on approximately 20,000 ha of rangeland burned by a wildfire in …


Utilization Of Crested Wheatgrass Plants By Cattle Under Several Grazing Regimes, Patricia Selann Johnson May 1987

Utilization Of Crested Wheatgrass Plants By Cattle Under Several Grazing Regimes, Patricia Selann Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Patterns of grazing on individual crested wheatgrass plants were studied using scale maps of plant basal outlines within randomly located plots. The occurrence and extent (part of plant grazed, stubble height) of grazing on each plant was recorded on the maps at two and three day intervals throughout a grazing treatment. Allometric equations for estimating phytomass from plant photosynthetic volume were generated using nonlinear regression analysis. Equations were specific to year. The percent weight remaining in the stubble of a grazed plant was estimated using a second-order polynomial equation relating cumulative percent plant height to cumulative percent plant weight. A …


Impact Of Development On Traditional Pastoralism In Somalia, Abdulkadir A. Handulle May 1987

Impact Of Development On Traditional Pastoralism In Somalia, Abdulkadir A. Handulle

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The Somali pastoral nomads live in an environmental condition of risk and uncertainty. The scarce and unreliable rainfall is the primary element ·which determines the existence of nomadic pastoralism. The lands devoted to pastoralism in Somalia are those arid and semi-arid areas that could not sustain cropping, so that pastoralism may be considered the only rational utilization of the land resource. Nomads live in an environment where the survival of both animals and plants are constrained by many factors such as droughts. Yet, both nomads and their animals have evolved by learning numerous adaptive strategies to cope with their harsh, …


Greater Yellowstone Ecosystem, U.S. House Committee On Insular Affairs Jan 1987

Greater Yellowstone Ecosystem, U.S. House Committee On Insular Affairs

All U.S. Government Documents (Utah Regional Depository)

No abstract provided.


Characteristics Of Successful Competitors: An Evaluation Of Potential Growth Rate In Two Cold Desert Tussock Grasses, Eissenstat D. M., Caldwell M. M. Jan 1987

Characteristics Of Successful Competitors: An Evaluation Of Potential Growth Rate In Two Cold Desert Tussock Grasses, Eissenstat D. M., Caldwell M. M.

Aspen Bibliography

Within the first few weeks after seedling emergence, Agropyron desertorum, a more competitive tussock grass, had a much higher mean relative growth rate (RGR) than Agropyron spicatum, a very similar, but less competitive species. However, beyond the early seedling stage, the two grasses had a remarkably similar whole-plant RGR in hydroponic culture and aboveground RGR in glasshouse soil, if root temperatures were above approximately 12° C. At soil temperatures between 5 and 12° C, A. desertorum exhibited a 66% greater aboveground RGR than A. spicatum (P < 0.05). Both species responded similarly to warming soil temperatures. In the field, however, tiller growth rates were generally similar. Neither species showed marked tiller elongation until a couple of weeks after snowmelt, by which time soil temperatures, at least to a depth of 10 cm, were above 12° C for a significant portion of the day. Above-ground biomass accumulation over a three-year period indicated that both grasses had similar potential growth rates whereas Artemisia tridentata ssp. vaseyana, a common neighbor planted in the same plots, had a much greater potential growth rate. The greater competitive ability of adult A. desertorum, as compared to A. spicatum, cannot be attributed to appreciable differences in potential growth rates.


Intercept Feeding As A Means Of Reducing Deer-Vehicle Collisions, Peggy Wood May 1986

Intercept Feeding As A Means Of Reducing Deer-Vehicle Collisions, Peggy Wood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Intercept feeding was tested for its efficacy in reducing deer-vehicle collision frequency by diverting deer movement patterns away from highways using alfalfa hay as an attractant. Ratios of roadkills in control vs. treatment zones of three highway segments indicated that feeding reduced collision frequency. Spotlighting counts of live deer were significantly higher (P < 0.001) in the control than in the treatment zone, supporting the effectiveness of feeding in keeping deer distant from the highway. In a benefit:cost analysis, the benefits accrued by reducing collision frequency exceeded the costs of feeding on each highway both years, with one exception: in 1986 one of the highways demonstrated that particular features of an area may not be conducive to effectively attracting deer away from a highway. I recommend intercept feeding be used with alternate techniques, so that the most appropriate technique is applied in each situation to reduce collision risk.


Belowground Resource Exploitation In Semiarid Plants: A Comparative Study Using Two Tussock Grasses That Differ In Competitive Ability, David M. Eissenstat May 1986

Belowground Resource Exploitation In Semiarid Plants: A Comparative Study Using Two Tussock Grasses That Differ In Competitive Ability, David M. Eissenstat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relative competitive abilities of Agropyron desertorum and Agropyron spicatum were compared using Artemisia tridentata transplants as indicator plants. Although these two tussock grasses have similar shoot growth forms and shoot physiological characteristics, they have substantial differences in their competitive abilities. Artemisia had lower survival, growth, reproduction, and water potential when transplanted into neighborhoods of A. desertorum than in neighborhoods of A. spicatum.

Plant attributes associated with the differences in competitive ability were explored. Agropyron desertorum and A. spicatum have remarkably similar potential growth rates at warm soil temperatures. In a prolonged cold soil temperature treatment in the greenhouse, …


Estimating Optimum Overstory Vegetation Reduction For Increasing Understory Production, John A. Tanaka May 1986

Estimating Optimum Overstory Vegetation Reduction For Increasing Understory Production, John A. Tanaka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to investigate analytical approaches for estimating the optimum (profit maximizing) rate of initial overstory kill for increasing seasonal forage availability on a specific ranch. The models were developed using the big sagebrush (Artemisia tridentata) - crested wheatgrass (Agropyron cristatum, A. desertorum) vegetation type on a Utah cow-calf-yearling operation as an example. The models should be applicable on any ranching situation where understory forage production is constrained by the establishment and growth of undesirable overstory vegetation.

Three model forms were developed and compared for their applicability to on-the-ground investment decision …


Carnivore Competition And Resource Use In The Serengeti Ecosystem Of Tanzania, George Walter Frame May 1986

Carnivore Competition And Resource Use In The Serengeti Ecosystem Of Tanzania, George Walter Frame

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coexisting ungulate-eating carnivores--lion, spotted hyena, cheetah, leopard, African wild dog, black-backed jackal, common jackal, and six species of vulture--are examined in East Africa's Serengeti ecosystem. Niche similarities year-round, by season, and by location are described using food, habitat, time of hunting, and other variables. Intraspecific niches of cheetah sex, age, and social groups show that male coalitions differ most from the others in hunting behavior and habitat use. Tests using the carnivore data failed to support hypotheses about niche breadth variation, niche overlap variation, range of food items, and niche inclusion. Densities of the five largest Carnivora in the 35,500 …


The Redevelopment Of Plant Community Diversity On A Surface Coal Mine In Southwestern Wyoming, Thomas Joseph Hatton May 1986

The Redevelopment Of Plant Community Diversity On A Surface Coal Mine In Southwestern Wyoming, Thomas Joseph Hatton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study was initiated in 1981 to investigate the redevelopment of plant communities on a recontoured, surface-mined site in southwestern Wyoming. The landscape pattern of vegetation was compared with topographic position, the initial topsoil pattern, and cultural practices including shrub planting density, shrub planting pattern and topsoil treatments for the years 1982-1985. In addition, differences in vascular plant species diversity within these various factors and treatments were determined, along with the trend in intracommunity (alpha), intercommunity (beta) and landscape (gamma) diversity for the entire study area.

The influence of site factors and tested cultural practices on the differentiation of the …


A Market Analysis For Adult Outdoor Education In Five Western States, Karla Joy Vanderzanden May 1986

A Market Analysis For Adult Outdoor Education In Five Western States, Karla Joy Vanderzanden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Organizations that offer Outdoor Education programs for adults are concerned with how to best attract people to their programs. Effective program design begins with a clear understanding of the people to be served. A marketing orientation--meeting the needs of participants--has begun to pervade non-profit management; specific information on the adult market for Outdoor Education remains limited. The purpose of this study was to identify and characterize segments based upon the benefits people seek from such an experience. Secondly, this analysis describes current programs 1n a five state region and identifies discrepancies between available and needed services.

A mail survey of …


Effect Of Short Duration Grazing On Soil Moisture Depletion And Plant Water Status In A Crested Wheatgrass Pasture, Jon M. Wraith May 1986

Effect Of Short Duration Grazing On Soil Moisture Depletion And Plant Water Status In A Crested Wheatgrass Pasture, Jon M. Wraith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A short duration grazing system was utilized to determine the effects of intensive periodic defoliation during spring on soil moisture depletion patterns and plant water status in a crested wheatgrass (Agropyron cristatum and A. desertorum) pasture in central Utah. Exclosures were constructed to compare grazed and ungrazed responses. Soil moisture was monitored to a depth of 193 cm at one to two week intervals from mid-April to late-September using a neutron moisture gauge. Predawn and midday leaf water potentials were estimated using a pressure chamber technique. The two paddocks included in the study were grazed three times between …


Animal Nutritional Response To Sward Structure Under Short Duration Grazing Management, Kenneth C. Olson May 1986

Animal Nutritional Response To Sward Structure Under Short Duration Grazing Management, Kenneth C. Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A ten-paddock short duration grazing cell was stocked with yearling heifers at a stocking rate of 0.7 ha per animal unit month and a stocking density of 0.14 ha per animal unit. A continuously-season- long-grazed (CSLG) pasture was used as a control. It was stocked at the same stocking rate, but at a stocking density of 1.4 ha per animal unit. Grazing periods in SDG paddocks were two or three days. Dietary quality was assessed by crude protein · content and in vitro digestibility of esophageal fistula estrusa samples. Three variables of ingestive behavior were measured, including ingestion rate, biting …


Revegetation Of Denuded High Elevation Watersheds In Mustang, Nepal, Madhukar Upadhya May 1986

Revegetation Of Denuded High Elevation Watersheds In Mustang, Nepal, Madhukar Upadhya

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Lack of vegetative cover largely caused by such human activities as firewood collection, intensive grazing, and deforestation have accelerated the process of desertification at high elevation watersheds in Nepal. Mountain environment at high elevation is delicate and regeneration of vegetation is slow. Livestock grazing and firewood collection are the basic needs of the people. However, constant human pressure on natural vegetation upsets the hydrologic processes and results in disastrous soil erosion. Desertification caused by long-term soil erosion in semi-arid regions of Mustang district (a severely desertified, high elevation area) in Nepal probably indicates the future of other high elevation watersheds, …


Mountain Pine Beetle Outbreaks In The Rocky Mountains: Effects On Fuels And Fire In Lodgepole Pine Forest (Abstract), W H. Romme, D H. Knight, J Fedders Jan 1986

Mountain Pine Beetle Outbreaks In The Rocky Mountains: Effects On Fuels And Fire In Lodgepole Pine Forest (Abstract), W H. Romme, D H. Knight, J Fedders

The Bark Beetles, Fuels, and Fire Bibliography

Changes in fuels were studied in northwestern Wyoming by sampling a sequence of ten stands that had been heavily damaged by beetles from 1 to 20 years earlier. Leaf litter increased only slightly (3-6%) for six years, and large woody fuels (which contribute much less to flammability) increased steadily and substantially (up to 16 x) for at least 20 years. Other fuel categories did not change significantly. While flammability may be increased during the first year or two after a beetle infestation because dead leaves are still on the trees, the risk of destructive fire during years 2-20 may be …


Relationships Among Aspen, Fungi, And Ungulate Browsing In Colorado And Wyoming, John H. Hart Jan 1986

Relationships Among Aspen, Fungi, And Ungulate Browsing In Colorado And Wyoming, John H. Hart

Aspen Bibliography

No abstract provided.


Seasonal Feeding Behavior And Forage Selection By Goats In Cleared And Thinned Deciduous Woodlands In Northeast Brazil, Roberto Cesar Magalhaes Mesquita May 1985

Seasonal Feeding Behavior And Forage Selection By Goats In Cleared And Thinned Deciduous Woodlands In Northeast Brazil, Roberto Cesar Magalhaes Mesquita

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The seasonal feeding behavior, forage preferences and body weight responses of goats were studied under three densities of woodland (called caatinga), and under three stocking rates. The experiment was located in the semi-arid tropics of northeastern Brazil at 3 42' South latitude, and 40 21' West longitude at an elevation of 75 meters. Mean annual precipitation of the area is 832 mm.

Removing the shrubs and trees increased yields of herbaceous only on partially-cleared sites. Goats gained body weight (kg BW/ha) during the wet season, with the cleared treatment showing the best body weight response per unit of land. However …


Growth And Water Relations Of Mountain Big Sagebrush On Reclaimed Mine Soils In Southwestern Wyoming, Alan T. Carpenter May 1985

Growth And Water Relations Of Mountain Big Sagebrush On Reclaimed Mine Soils In Southwestern Wyoming, Alan T. Carpenter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mined-land reclamation practices in shrub-steppe ecosystems can be augmented by planting seedlings of locally dominant shrubs, e.g., mountain big sagebrush. Dispersion pattern could affect sagebrush performance by influencing amounts of windborne snow, soil and litter which accumulate around shrubs and by influencing water withdrawal by roots. Mountain big sagebrush seedlings were planted in plots on a reclaimed coal strip mine in two dispersion patterns: singly and in clumps of four at the same overall density.

Performance of mountain big sagebrush was monitored during two growing seasons. Measures included plant survival, end-of-growing season aboveground biomass, leaf water potential components, soil water …


Behavioral Response Of Desert Bighorn Sheep To Human Harassment: A Comparison Of Disturbed And Undisturbed Populations, Michael M. King May 1985

Behavioral Response Of Desert Bighorn Sheep To Human Harassment: A Comparison Of Disturbed And Undisturbed Populations, Michael M. King

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Desert bighorn sheep (Ovis canadensis nelsoni) response to human disturbance was evaluated in southeastern Utah from 1981-1983. Bighorn response was compared between the Red Canyon area, an area with relatively high levels of human disturbance, and the White Canyon area, an area with relatively low levels of human disturbance. Bighorn were deliberately harassed by vehicles and hikers and immediate response and distance fled were recorded. When bighorn remained in the presence of the harassing stimuli, actual time spent in and proportion of animals engaged in various behaviors were recorded to determine group wariness and activity budgets under harassed …