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Articles 1171 - 1200 of 1588
Full-Text Articles in Ecology and Evolutionary Biology
Comparison Of Methods For Detecting Voles Under Apple Trees, Mark E. Tobin, Milo E. Richmond, Richard M. Engeman
Comparison Of Methods For Detecting Voles Under Apple Trees, Mark E. Tobin, Milo E. Richmond, Richard M. Engeman
Wildlife Damage Management Conference
We conducted a study in 2 heavily infested orchards in the mid-Hudson Valley of New York to evaluate methods for detecting the presence of meadow voles (MV, Microtus pennsylvanicus) and pine voles (PV, M. pinetorum) under apple trees. We quantified several possible signs indicating the presence of voles in each of the 4 quadrants under the canopy of each tree, and then set and monitored traps until capture success in the orchard declined to zero. There was no evidence that the 4 quadrants differed with respect to any of the variables examined. The apple slice index (ASI) was …
Effectiveness Of A Vertical 3-Wire Electric Fence Modified With Attractants Or Repellents As A Deer Exclosure, Don M. Jordan Jr., Milo E. Richmond
Effectiveness Of A Vertical 3-Wire Electric Fence Modified With Attractants Or Repellents As A Deer Exclosure, Don M. Jordan Jr., Milo E. Richmond
Wildlife Damage Management Conference
We conducted experiments with behavioral conditioning of white-tailed deer (Odocoileus virginianus) using vertical 3-wire, electrified fencing modified with either an attractant or a repellent in order to test the idea that an attractant or repellent, coupled with an electric shock, would be a more effective deterrent than a random shock or no shock at all. Exclosures measuring 6 x 6 m with 3 wires at heights of 50, 100, and 150 cm were established at 2 study sites in Tompkins County, New York. Each site contained 4 exclosures which were either nonelectrified (control), electrified, electrified with an attractant, …
Perceptions And Realities: When Does 2 + 2 = 5?, Robert M. Timm
Perceptions And Realities: When Does 2 + 2 = 5?, Robert M. Timm
Wildlife Damage Management Conference
Perception and reality. One and the same, or are they different? There are certainly a diversity of perceptions. Are there also multiple realities?
The Quabbin Reservation White-Tailed Deer Impact Management Plan: A Case History, James A. Parkhurst, Robert W. O'Connor
The Quabbin Reservation White-Tailed Deer Impact Management Plan: A Case History, James A. Parkhurst, Robert W. O'Connor
Wildlife Damage Management Conference
Quabbin Reservation, a 22,662-ha watershed management area located in west-central Massachusetts, is experiencing moderate to severe browsing pressure by white-tailed deer (Odocoileus virginianus) on much of the reservation's forested land. In many areas, park-like habitat exists where natural regeneration of the dominant mixed oak (Quercus spp.) forest has been severely repressed, or outright eliminated, due to repetitive browsing by deer. Understory composition is now dominated by patches of blueberry (Vaccinium angustifolium), huckleberry (Gaylussacia baccata), thick carpets of hay-scented fern (Dennstaedtia punctilobula), and grasses. Managers are concerned that as the forest ages …
Interactions Between People And Wildlife In Urbanizing Landscapes, John Hadidian
Interactions Between People And Wildlife In Urbanizing Landscapes, John Hadidian
Wildlife Damage Management Conference
In little more than 100 years, America has been transformed from a rural to an urban society in which 8 out of every 10 people live in cities or associated metropolitan areas. This change has affected the way that people interact with wildlife and has introduced new and unique situations in which human-wildlife conflicts arise and must be dealt with. Most urban wildlife problems occur in and around primary residences or nodes (e.g., airports, golf courses, lake fronts) and involve only a few species. This relationship may change as urban landscapes mature or expand through restoration efforts, or as more …
Public Involvement In Coyote Management Decisions, Robert A. Inslerman
Public Involvement In Coyote Management Decisions, Robert A. Inslerman
Wildlife Damage Management Conference
In 1990, the Legislature passed a bill that would have allowed year-round hunting of coyotes (Canis latrans) in New York's Northern Zone, as opposed to the current system of open and closed hunting seasons established annually by Department of Environmental Conservation (DEC) regulation. The bill generated such controversy that it was withdrawn pending a study by DEC. The objectives of the study were to: (1) assess the role of the coyote in northern New York in relation to people, wildlife, and livestock; (2) provide adequate opportunity for citizens to express their opinions concerning coyotes; and (3) prepare a …
Tapping The Potential Of The Wildlife Rehabilitation Community For Public Education About Wildlife Damage Management, William F. Siemer, Tommy L. Brown, Patrick P. Martin, Randall D. Stumvoll
Tapping The Potential Of The Wildlife Rehabilitation Community For Public Education About Wildlife Damage Management, William F. Siemer, Tommy L. Brown, Patrick P. Martin, Randall D. Stumvoll
Wildlife Damage Management Conference
Wildlife rehabilitators frequently interact with the public, but the extent and impact of their activities as public educators had never been well documented in New York State. In 1991 the New York State Department of Environmental Conservation (DEC) sponsored a mail survey of all 430 rehabilitators in New York to address this information need. Rehabilitators showed high interest and involvement in public education, and they reached a large audience, suggesting that they may hold potential as contributors to public education concerning wildlife damage control. Realizing that potential offers an incentive for DEC to work more closely with rehabilitators to provide …
Control Of Ring-Billed Gulls And Herring Gulls Nesting At Urban And Industrial Sites In Ontario, 1987-1990, Hans Blokpoel, Gaston D. Tessier
Control Of Ring-Billed Gulls And Herring Gulls Nesting At Urban And Industrial Sites In Ontario, 1987-1990, Hans Blokpoel, Gaston D. Tessier
Wildlife Damage Management Conference
Large numbers of ring-billed gulls (Larus delawarensis) and much smaller numbers of herring gulls (L. argentatus) have begun to nest at several industrial and urban sites in the Canadian Great Lakes causing a flight safety problem (nesting at end of a runway), disrupting commercial operations (nesting on roads and storage yards), and creating nuisances (noise and smell of the colony and defecations on equipment). Gulls were prevented from nesting by scaring (using tethered birds of prey, moving vehicles, and foot patrols equipped with cracker shells) or by physically excluding them (by installing monofilament lines). At some …
Strategies To Control Rodent Damage In Sugar Bushes: An Update, Alan May, John Austin, Dennis Slate
Strategies To Control Rodent Damage In Sugar Bushes: An Update, Alan May, John Austin, Dennis Slate
Wildlife Damage Management Conference
Efficacy trials using zinc phosphide (ZP) steam-rolled oats (2% a.i., EPA Reg. No. 56228-5), and cholecalciferol mixed (CHOL) grain bait (.075% a.i., EPA Reg. No. 12455-57), were conducted during summer 1990 to compare their effectiveness in controlling rodent damage to plastic tubing systems used to collect sap from sugar maples (Acer saccharum) in Vennont A 24( c) Special Local Needs registration for ZP to control rodent damage has existed in Vennont since the 19(i()s. However, no fonnal efficacy trials have been conducted for this specific use of ZP, and the previous supplemental label did not include instructions for …
Use Of Drc-1339 To Eliminate Gulls And Re-Establish A Tern Nesting Colony In Buzzards Bay, Massachusetts, Bradford G. Blodget, Laura Henze
Use Of Drc-1339 To Eliminate Gulls And Re-Establish A Tern Nesting Colony In Buzzards Bay, Massachusetts, Bradford G. Blodget, Laura Henze
Wildlife Damage Management Conference
DRC-1339 was used in 1990 and 1991 to reverse gull (Laridae) domination at Ram Island in Mattapoisett, Massachusetts, a site historically important to the endangered roseate tern (Sterna dougallii). Reduction of the very dense gull population at Ram Island and reclamation of the island for nesting terns is seen as a challenge, especially considering the site's proximity to New Bedford, the largest commercial fishery on the Atlantic Seaboard. During 1990 and 1991, gull productivity at Ram Island was completely suppressed. Eight hundred twenty-three and 172 gulls were recovered dead following treatments in 1990 and 1991. Females predominated nearly …
Educational Opportunities At The University Of Nebraska-Lincoln, Scott E. Hygnstrom
Educational Opportunities At The University Of Nebraska-Lincoln, Scott E. Hygnstrom
Wildlife Damage Management Conference
University students, particularly those enrolled in natural resources programs, make up one of the smallest, yet potentially most important and influential audiences for wildlife damage professionals. Considering that these students will be tomorrow's natural resources technicians, biologists, and administrators, I feel that it is critical that we provide them factual information about wildlife damage to increase their awareness of potential problems and solutions, and increase their ability to make well-informed decisions.
Reproductive Ecology Of Wyoming Big Sagebrush (Artemisia Tridentata Ssp. Wyomingensis) : Effects Of Herbivory And Competition, Richard T. Decker
Reproductive Ecology Of Wyoming Big Sagebrush (Artemisia Tridentata Ssp. Wyomingensis) : Effects Of Herbivory And Competition, Richard T. Decker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Herbivory and plant competition affect sexual reproduction of plants in various ways. Exclusion of mule deer (Odocoileus hemionus) and cattle, removal of plant competition (both inter- and intraspecific), and all combinations of the above treatments were used to examine the individual and combined affects on Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush) reproduction. Reproduction of Artemisia tridentata ssp. wyomingensis was divided into hierarchical levels of the number of: (1) modules per current-year ' s growth (CYG), (2) nodes per module, (3) inflorescence heads per node, (4) achenes per inflorescence head and (5) percent viable achenes. Counts at hierarchical …
Forest Canopies: Form And Functional Relationships, Steven B. Jack
Forest Canopies: Form And Functional Relationships, Steven B. Jack
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Forest canopy structure is strongly influenced by stand density due to changing competitive interactions among the individual trees and in turn directly influences stemwood volume production. The structure and dynamics of forest canopies, particularly in relation to the production of stemwood, were examined in unmanaged, even-aged stands of two dissimilar tree species, Pinus contorta var. latifolia Engelm. and Abies lasiocarpa (Hook.) Nutt. The analysis of structure-production relationships was guided by a conceptual model which generated hypotheses and led to examination of assumptions incorporated in the model.
Mean crown dimensions were related to stand density through a negative exponential function for …
Comparative Foraging Ecology Of Sheep And Goats In Caatinga Woodland In Northeastern Brazil, Scott L. Kronberg
Comparative Foraging Ecology Of Sheep And Goats In Caatinga Woodland In Northeastern Brazil, Scott L. Kronberg
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Small-ruminant production is an important part of the agricultural economy of northeastern Brazil. However, mild-to-severe undernutrition of livestock is an annual occurrence. Goats can tolerate the marginal forage conditions better than sheep, but the mechanisms underlying their superior tolerance are not understood.
An analysis of animal liveweights at the end of the year-long study indicated that reproducing mixed-race goats gained nearly twice (P<.05) the weight of reproducing hair-sheep of the Santa Ynez breed, and non-reproducing goats gained about 1.2 times more (P<.05) weight than non-reproducing sheep. Daily weight gains of lambs were less (P<.10) than those of kids for their first 80 days of life.
In the wet season, reproducing sheep and goats gained similar (P>.05) weight, while non-reproducing sheep gained more (P≤.05) than non-reproducing goats. Non-reproducing goats had greater (P<.05) forage organic matter intake (OMI) than the corresponding sheep in the two wet periods. In the late-wet period, non-reproducing goats had greater (P<.05) digestible energy intake (DEI) than corresponding sheep did but had similar (P>.05) digestible protein intake (DPI) as sheep.
In the dry …
The Effect Of Seasonal Cattle Grazing On California Bighorn Sheep Habitat Use, Melanie J. Steinkamp
The Effect Of Seasonal Cattle Grazing On California Bighorn Sheep Habitat Use, Melanie J. Steinkamp
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The effect of seasonal cattle grazing on a newly reintroduced population of California bighorn sheep (Ovis canadensis californiana) in Big Cottonwood Canyon, Idaho, was studied. The hypothesis that bighorn sheep avoid cattle was tested. The issue of avoidance between bighorn sheep and livestock is arguable. Some studies have found that bighorn sheep avoid cattle while others have found no response of bighorn sheep to cattle.
Evidence was found to document the avoidance of cattle by bighorn sheep. The size of the bighorn's home range and core area decreased with the movement of cattle into areas of high bighorn …
The Effects Of Disease, Prey Fluctuation, And Clear-Cutting On American Marten In Newfoundland, Canada, Richard J. Fredrickson
The Effects Of Disease, Prey Fluctuation, And Clear-Cutting On American Marten In Newfoundland, Canada, Richard J. Fredrickson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Individual variation in survival and behavior of American marten (Martes americana) was studied in relation to disease, prey fluctuation, and clear-cutting from 10 January 1986 through 20 August 1987 in Newfoundland, Canada. Thirty-seven of forty marten captured on the study area were telemetered and monitored for part or all of the study.
Marten mortality was concentrated in two intervals, fall 1986 and late winter 1987. Mortality during fall 1986 was attributable to encephalitis, while marten deaths during late winter 1987 resulted from predation and starvation attributable to the prey decline. Nonsuppurative encephalitis was first detected 7 October 1986; …
A Descriptive Study Of Range Livestock Operations In The Somali Central Rangelands, Abdinasir M. Abdulle
A Descriptive Study Of Range Livestock Operations In The Somali Central Rangelands, Abdinasir M. Abdulle
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Information on livestock operations, particularly what kind of livestock operations are practiced in the Somali central rangelands, and how these operations differ for different herders in different vegetation types and farming systems, could serve as a major tool in making management decisions. This study provides a detailed description of range livestock operations in the Somali Central Rangelands. It also answers some important management questions.
Range livestock operations were inventoried through personal interviews with the owners and herders. Data are supplemented by previous nation-wide and regional survey statistics. Herd productivity data which include herd structures, age, age-related sales, slaughters, gifts, and …
Yellowstone's Northern Elk Herd: Critical Evaluation Of The "Natural Regulation" Paradigm., Charles Edward Kay
Yellowstone's Northern Elk Herd: Critical Evaluation Of The "Natural Regulation" Paradigm., Charles Edward Kay
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Prior to 1968, the National Park Service contended that an unnaturally large population of elk had severely damaged Yellowstone Park's northern winter range, including aspen and willow communities. However, under "natural regulation" management adopted in the earl y 1970s the agency now believes that vegetation changes in the park are due to normal plant succession, climatic change, or fire suppression, not ungulates. The agency also believes that large numbers of elk (12, 000 - 15, 000) have wintered on the park's northern range for the last several thousand years. This study tested several of the major assumptions or predictions of …
An Analysis Of Institutional Approaches For Management Of Common Rangeland Resources In Sub-Saharan Africa, Mohale Gabriel Sekoto
An Analysis Of Institutional Approaches For Management Of Common Rangeland Resources In Sub-Saharan Africa, Mohale Gabriel Sekoto
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
The purpose of this report is to address the issues that are relevant to the management of common rangeland resources in Sub-Saharan Africa. I feel that the issues presented here are among some of those which are important and need to be considered in order to understand the kind of performance perceived about the efforts to develop the range and livestock in pastoral societies. In this report, three case studies have been reviewed, regarding institutional approaches tried to manage common rangelands. These case studies are about group ranches in Kajiado District, Kenya and in Upper Volta and the Sehlabathebe Grazing …
Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson
Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Root exploitation of enriched soil microsites was examined for the tussock grasses Agropyron desertorum and Agropyron spicatum and the shrub Artemisia tridentata. Two mechanisms of exploitation of the microsites were examined: root proliferation and changes in nutrient uptake capacity. One day after nutrient solution was applied to small soil patches, the mean relative growth rate of Agropyron desertorum roots in enriched patches was two to four times greater than for roots of the same plants in soil patches treated with distilled water. This rapid and striking root proliferation occurred in response to N-P-K enrichment as well as to P or …
Modeling Forest Dynamics Based On Stand Level Resource Allocation, Geoffrey Candler Poole
Modeling Forest Dynamics Based On Stand Level Resource Allocation, Geoffrey Candler Poole
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
An ecologically based model of forest succession is presented. In the model, trees compete for a share of limited growth resources available from their environment. Competition is reflected by each tree's effect on the resource pool and is not explicitly modeled. Model parameters were fit to field data from subalpine forests of the Rocky Mountains. A technique for estimating model parameters from understory-tolerance rankings and silvical characteristics of each species is also presented. The model's output was consistent with our current understanding of forest dynamics. Emergent properties of the model also mimicked natural processes such as self-thinning, release, and maximum …
Fee Hunting Opportunities On Private Land In Utah: An Economic And Policy Analysis, Lucy A. Jordan
Fee Hunting Opportunities On Private Land In Utah: An Economic And Policy Analysis, Lucy A. Jordan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Objectives of this research were (1) to describe fee hunting as it is currently practiced in Utah and (2) to assess the adequacy of fee hunting efforts in addressing the problems of wildlife habitat and hunter access on private land. To collect information, Utah landowners who charged for deer (Odocoileus hemionus) or elk (Cervus elaphus) hunting in 1986 were surveyed by telephone and mail.
Compared to the average Utah livestock rancher, those involved in fee hunting have larger livestock operations and have owned their property longer. They are Utah natives. Fee hunting is concentrated in northern …
Using Computer Imaging To Assess Visual Impacts Of Forest Insect And Disease Pests, Daniel Rabin
Using Computer Imaging To Assess Visual Impacts Of Forest Insect And Disease Pests, Daniel Rabin
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Forest insect and disease pests alter the appearance of trees, thereby impacting visual resources. Because of the complexity of most forest landscapes, the degree of visual impact of pest-infested forest stands is difficult to quantify.
This paper describes a method of measuring visual impacts of pest-infested forest stands. Photographs of healthy Ponderosa pine trees were entered into a computer video-image-processing system. Using this system, images of trees were altered to simulate different degrees of infestation by limb rust, a forest pathogen.
The altered and unaltered images were shown to groups of observers who rated the scenes in terms of "scenic …
Management, Foraging Behavior, Diet Composition And Forage Quality Of Free-Ranging But Herded Camels In Ceeldheer District, Central Somalia, Ahmed A. Elmi
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In Somalia, camel (Camelus dromedarius) survivability and milk production has been higher than for other domestic livestock and contributes substantially to the subsistence of Somali pastoralists. The objective of this research was to study management, foraging behavior and nutrition of camels in their natural habitat to determine how production continues under seasonal nutritional stress.
Management systems of Ceeldheer pastoralists are based on available natural pasture and water. The natural rotation grazing system maintained an ecological equilibrium in the District.
Pastoralists manipulate their herds to suit existing environmental conditions, family needs and labor availability for herding. In herd management, …
The Feasibility Of River Otter Reintroduction In Northern Utah, Joel P. Bich
The Feasibility Of River Otter Reintroduction In Northern Utah, Joel P. Bich
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this thesis is to document river otter (Lutra canadensis) distribution and reintroduction potential in northern Utah. Distribution was studied using data from 3 sources: 1) otter sighting records from Utah Division of Wildlife Resources; 2) surveys of Utah furbearer trappers and natural resources personnel; and 3) searches of streams for otter sign. Potential for river otter habitat/reintroduction was evaluated by assessing food, cover, and reintroduction attributes. Streams were ranked using an evaluation system based on data from the otter literature.
Forty-six positive otter sightings were made in Utah by trappers, natural resources personnel, and the …
Deer And Forestry In Germany: Half A Century After Aldo Leopold, Michael L. Wolfe, Friedrich-Christian V. Berg
Deer And Forestry In Germany: Half A Century After Aldo Leopold, Michael L. Wolfe, Friedrich-Christian V. Berg
Aspen Bibliography
No abstract provided.
Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone
Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Diversionary feeding, artificial feeding designed to divert animals away from areas where they might cause property damage, was tested for efficacy in reducing fruit orchard browsing by big game animals during two consecutive winters in Utah. Strategically placed attractive feedstuffs lured deer to feed stations and reduced fruit-bud browsing (1st year, P < 0.07; 2nd year, P < 0.01). Blossom and apple numbers were greater (P < 0.05) on trees in the feed (treatment) orchard than in the no feed (control) orchard in each year. However, higher (P < 0.05) apple production on trees where browsing was excluded in the treatment orchards compared to the control orchards indicated that intercept feeding did not increase crop production. Tree periodicity and other factors affecting apple production masked the effect of diversionary feeding on crop yield.
Two independent browsing damage assessment methods, a paired-tree technique and a harvest-inflation technique, predicted that the ratio of apples lost per browsed bud was 0.158 and 0.082, respectively. However, the values of the ratio varied widely with each method of estimation. Browsing damage differed ( …
The Effects Of Forest Harvesting On Small Mammals In Western Newfoundland And Its Significance To Marten, Brian Tucker
The Effects Of Forest Harvesting On Small Mammals In Western Newfoundland And Its Significance To Marten, Brian Tucker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The depauperate fauna of Newfoundland provides a limited prey base for marten. Only two small mammal prey species, Microtus pennsylvanicus and Sorex cinereus, were found in any abundance in the old-growth forests of the study area. Of these two, Microtus displayed population fluctuations typical of most microtines. Analysis of marten scats indicated that Microtus is a very important prey item to the marten with other food. items being of lesser importance particularly when Microtus are abundant.
Trapping in various habitats indicated that Sorex densities were three to five times higher in logged areas compared to uncut areas. Unfortunately, the …
A New Approach To Forest Site Quality Modeling, David L. Verbyla
A New Approach To Forest Site Quality Modeling, David L. Verbyla
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Multiple regression and discriminant analysis procedures are commonly used to develop forest site quality models. 'When they contain many independent variables relative to sample size, these models may be subject to predicton bias. Fit statistics such as R2 in regression and classification tables in discriminant analysis show the apparent model accuracy but this may be a biased estimate of the model's actual accuracy. Sample splitting methods such as cross-validation and the bootstrap can be used to get an unbiased actual accuracy estimate.
A discriminant procedure called classification tree analysis uses cross-validation to build the classifier with the greatest estimated …
Nutrient And Water Interrelationships Between Crested Wheatgrass And Two Shrub Species, Paul B. Baker
Nutrient And Water Interrelationships Between Crested Wheatgrass And Two Shrub Species, Paul B. Baker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
When crested wheatgrass (Agropyron desertorum) grows in mixture with sagebrush (Artemisia tridentata), its production declines. Its production increases when grown in mixture with fourwing saltbush (Atriplex canescens), according to previous reports. This study investigated soil water extraction and potassium (K) nutrition of the two shrubs to identify possible causes of the differential responses of crested wheatgrass.
Crested wheatgrass had reduced, rather than increased, nitrogen (N) and K yield in mixture with fourwing saltbush. No differences in N and phosphorous (P) concentrations were observed between sagebrush and fourwing saltbush, but fourwing saltbush had a much …