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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

Eastern Wildlife Damage Control Conference: 3rd (1987)

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.


Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen Aug 1987

Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen

Publications (WR)

In February, 1982 I began a year-long study to determine if growth and reproduction in Daphnia Pulex were limited by the amount of food available in Boulder Basin, Lake Mead. To determine this, I made monthly collections of Daphnia Pulex and natural lake seston from an already established station in Boulder Basin. I cultured the Daphnia Pulex under simulated field conditions in a flow-through feeding apparatus using four different food regimes; 1-natural lake seston filtered through 80 um mesh to remove other zooplankton, 2-lake seston (as above) with an enrichment of 103 cells-ml-1 of Chlamydomonas reinhardti, 3-lake …


Analysis Of The Water-Quality Standards Proposed By The Nevada Division Of Environmental Protection, City Of Las Vegas, Nevada Aug 1987

Analysis Of The Water-Quality Standards Proposed By The Nevada Division Of Environmental Protection, City Of Las Vegas, Nevada

Publications (WR)

The Nevada Division of Environmental Protection (DEP) has proposed water-quality standards, applicable to Las Vegas Bay and Lake Mead, for (1) chlorophyll, (2) un-ionized ammonia, and (3) pH.

We have concluded that the proposed standards are unlikely to protect or improve water quality in Lake Mead. The proposed chlorophyll standard:

May harm the fishery. Lakes with more chlorophyll have greater fish production.

Will not improve clarity. Chlorophyll concentrations above 30 ug/1 have little effect on clarity.

Will not protect against scums or dominance by blue-green algae. Lake Mead shows no consistent relationship between chlorophyll and scums or blue-green dominance.

Will …


Comparison Of Littoral And Limnetic Zooplankton Communities Of Lake Mead, Patrick Joseph Sollberger May 1987

Comparison Of Littoral And Limnetic Zooplankton Communities Of Lake Mead, Patrick Joseph Sollberger

Publications (WR)

Microfaunal communities were studied in littoral (inshore) and limnetic (offshore) areas of the lower basin in Lake Mead to compare species composition and abundance between the two zones. Planktonic forms (zooplankton) dominated inshore and offshore habitats and the occurrence of littoral species was low. Therefore, high similarity in zooplankton species composition was found among all sampling stations. This was perhaps due to two main factors: (i) the physical and chemical environment among the stations were very similar and (ii) the lack of aquatic vegetation in the littoral zone reduced the occurrence of littoral species.

Although species composition did not vary …


Control Of Ecosystem Processes By Prairie Dogs And Other Grassland Herbivores, James K. Detling, April D. Whicker Apr 1987

Control Of Ecosystem Processes By Prairie Dogs And Other Grassland Herbivores, James K. Detling, April D. Whicker

Great Plains Wildlife Damage Control Workshop Proceedings

Black-tailed prairie dogs in the mixed-grass prairie at Wind Cave National Park, South Dakota, create habitat patches characterized by altered species composition, lower standing crops of plants, but higher forage quality. Native wildlife species such as bison, pronghorn, and elk preferentially feed on these prairie dog colonies and likely derive nutritional benefits from doing so.


Efficacy Of Deferred Grazing In Reducing Prairie Dog Reinfestation Rates, Kelly A. Cable, Robert M. Timm Apr 1987

Efficacy Of Deferred Grazing In Reducing Prairie Dog Reinfestation Rates, Kelly A. Cable, Robert M. Timm

Great Plains Wildlife Damage Control Workshop Proceedings

Population growth of black-tailed prairie dogs (Cynomys ludovicianus) was studied in 1985 and 1986 at 20 prairie dog towns on short- and mixed-grass rangeland in western Nebraska, to determine the efficacy of 2 years deferred (May 1 - Sept. 1) grazing in reducing population growth rates following population reduction. In 1985, population growth measures on deferred sites were not significantly different from grazed sites, perhaps due to drought conditions. In 1986, natality and population growth (% increase in animals) were significantly lower on deferred sites than on sites grazed by livestock. Deferred sites studied both years showed significant …


Management Of Prairie Dog Populations In Wind Cave National Park, Richard W. Klukas Apr 1987

Management Of Prairie Dog Populations In Wind Cave National Park, Richard W. Klukas

Great Plains Wildlife Damage Control Workshop Proceedings

Since the late 1920's there have been periodic control programs on black-tailed prairie dogs in Wind Cave National Park. The most recent control effort, which began in 1982, resulted in the reduction of total dogtown acreage from 2,000 to 750 acres. Recent studies carried out within the park have provided managers with more soundly based justification for carrying out control programs. The same information also points to the importance of maintaining prairie dog populations at or above certain minimum levels and the need for integrating this control program with several of the other resource management programs being carried out in …


The Prairie Naturalist Volume 19, No. 1 March 1987 Mar 1987

The Prairie Naturalist Volume 19, No. 1 March 1987

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

TABLE OF CONTENTS

ECOLOGY OF WHITE-TAILED DEER IN UPLAND PONDEROSA PINE HABITAT IN SOUTHEASTERN MONTANA ▪ G. L. Dusek

PRECISION AND BIAS OF A SUMMER AERIAL TRANSECT CENSUS OF PRONGHORN ANTELOPE ▪ S. H. Allen and J. M. Samuelson

ACTIVITY PATTERNS, MOVEMENTS, AND HOME RANGES OF PRAIRIE MINK ▪ T. W. Arnold and E. K. Fritzell

BRYOPHYTES OF THE SOUTH UNIT OF THEODORE ROOSEVELT NATIONAL PARK, NORTH DAKOTA ▪ C. L. Blaney and D. H. Norris

FALL FOOD HABITS OF WILD TURKEYS IN SOUTH CENTRAL …


The Exclusive Economic Zone-Considerations For Management With Special Reference To Developing Nations, John G. Catena Jan 1987

The Exclusive Economic Zone-Considerations For Management With Special Reference To Developing Nations, John G. Catena

Marine Affairs Theses and Major Papers

Having successfully initiated and developed the legal aspects of the Exclusive Economic Zone (EEZ) the challenge which now arises for the developing coastal nations is to implement an ocean management system to more fully realize the potential benefits of extended jurisdiction. This study discusses the needs and problems developing nations may encounter in developing such a management system and also considers the ways and means to meet these needs and overcome these problems. The study suggests that coastal nations should adopt an integrated three phased ocean policy process consisting of a (1) priority establishment phase (policy formulation) (2) strategic phase …


Pesticide Use And Toxicology In Relation To Wildlife: Organophosphorus And Carbamate , Compounds, Gregory J. Smith, U.S. Department Of The Interior, Fish And Wildlife Service Jan 1987

Pesticide Use And Toxicology In Relation To Wildlife: Organophosphorus And Carbamate , Compounds, Gregory J. Smith, U.S. Department Of The Interior, Fish And Wildlife Service

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

The use of organophosphorus and carbamate pesticides has increased markedly during the past two decades. Currently, more than 100 different organophosphorus and carbamate chemicals are registered as the active ingredients in thousands of different pesticide products in the United States. More than 160 million acre-treatments of these pesticides are estimated to be applied to agricultural crops and forests each year. Clearly, these two groups of chemicals constitute a major portion of all pesticides used today. Organophosphorus and carbamate compounds have histories dating back long before their use as pesticides. Carbamates were developed during investigation of "ordeal" poisons used in Africa …


Consumption Of Water By Livestock, G J. Luke Jan 1987

Consumption Of Water By Livestock, G J. Luke

Resource management technical reports

No abstract provided.


Broadacre Pest Control After Ddt, P J. Michael Jan 1987

Broadacre Pest Control After Ddt, P J. Michael

Journal of the Department of Agriculture, Western Australia, Series 4

DDT may no longer be applied to broadacre crops grown in Western Australia. It is being replaced by other more effective chemicals and with new methods of pest control. DDT was the most effective chemical for the control of several major broadacre pests in this State and farmers may well wonder why this change was necessary and how they will manage without DDT.


Effect Of Agronomic Practices On Wheat Protein Levels, M G. Mason Jan 1987

Effect Of Agronomic Practices On Wheat Protein Levels, M G. Mason

Journal of the Department of Agriculture, Western Australia, Series 4

High grain protein levels are preferred for many end-uses of wheat. However, there has been little or no incentive for farmers to use practices which would increase protein levels, because wheat payments are made without a price differential for proteinlevel, except where wheat could qualify for the Australian Hard grade.


The State Of Tampa Bay 1986, Agency On Bay Management Jan 1987

The State Of Tampa Bay 1986, Agency On Bay Management

Reports

When the Tampa Bay Regional Planning Council created the Agency on Bay Management, it charged the group with preparing an annual status of the condition of Tampa Bay, the state's largest open water estuary. Therefore, pursuant to the adopted rules of the Council's Agency on Bay Management, this document is the first State of Tampa Bay report. This report includes a discussion of the history of the Agency, an evaluation of how well the bay is doing environmentally and recommendations about what needs to be done in the work program aimed at improving Tampa Bay.


Rainbow Trout Cage Culture Utilizing Different Strains, Stocking Densities, And Feeding Methods In Eastern South Dakota Dugout Ponds, Jay Patrick Maher Jan 1987

Rainbow Trout Cage Culture Utilizing Different Strains, Stocking Densities, And Feeding Methods In Eastern South Dakota Dugout Ponds, Jay Patrick Maher

Electronic Theses and Dissertations

Rainbow trout (Salmo gairdneri) cage culture techniques were investigated in dugouts as part of a continuing program to evaluate the potential of small-scale, landowner-based aquaculture operations. Trout raised in the study did not reach a marketable size (200 g) due to the short growing season and small size at stocking. No significant (P >0.05) differences in growth were detected between stocking densities of 60, 80, 100, and 120 fish/m³. Demand feeding resulted in significantly greater length (P≤0.01), weight (P≤0.01), and relative weight (P≤0.05) than hand feeding in both years tested. Rainbow trout of the Hildebrand strain reached a significantly greater …


Habitat Selection And Sexual Suggestion Of Rocky Mountain Bighorn Sheep In Custer State Park, South Dakota, Larry J. Layne Jan 1987

Habitat Selection And Sexual Suggestion Of Rocky Mountain Bighorn Sheep In Custer State Park, South Dakota, Larry J. Layne

Electronic Theses and Dissertations

Spatial segregation between Rocky Mountain bighorn sheep (Ovis canadensis canadensis) ram and ewe herds has been documented by Geist (1971), Geist and Petocz (1977), Shank (1979), Morgantini and Hudson (1981), and Hogg (1983), where ram herds consist of mature males approximately 4 years old and older and ewe herds are comprised of all other individuals. Geist (1971), Shank (1979), and Hogg (1983) have shown that segregation occurs year-round except during the breeding season (November and December) when the sexes congregate on a traditional breeding range (cf. Geist 1971, p 209). These studies also have shown that the sexes remain separated …


Production From Heifers And First Calvers, G J. Sawyer Jan 1987

Production From Heifers And First Calvers, G J. Sawyer

Journal of the Department of Agriculture, Western Australia, Series 4

Heifers and first calvers present the major problems of the beef breeding herd. Reproduction rates, calf growth and survival of first calvers are generally much poorer than those of adult breeders.

Early successful reproductive performance is important in beef herds because of the high overhead cost of keeping breeding beef heifers or cows, Where possible, beef producers should aim to join heifers at 14 to 15 months of age. To achieve this goal, producers should set production targets for those animals. These targets will differ from farm to farm depending on when calves are turned off and the seasonal feed …


Effects Of Fire In The Northern Great Plains, Kenneth F. Higgins, Arnold D. Kruse, James L. Piehl Jan 1987

Effects Of Fire In The Northern Great Plains, Kenneth F. Higgins, Arnold D. Kruse, James L. Piehl

SDSU Extension Circulars

Fire has been used inconsistently to manage native and tame grasslands in the Northern Great Plains (NGP) of the north-central U.S. and south-central Canada, particularly the grasslands found in prairies, plains, agricultural land retirement programs, and moist soil sites. This has happened for three primary reasons: (1) the reduction of American Indian use of fire after 1875, (2) fire suppression and land use changes that put increasingly more acres under annual tillage since about the same time, and (3) a growing resistance to the use of fire since about 1940, largely due to media overemphasis of its harmful effects (e.g., …


Blackbird And Starling Feeding Behavior On Ripening Corn Ears, Glen E. Bernhardt, Lynda Van Allsbur, Richard A. Dolbeer Jan 1987

Blackbird And Starling Feeding Behavior On Ripening Corn Ears, Glen E. Bernhardt, Lynda Van Allsbur, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

The behavior of red-winged blackbirds {Agelaius phoemcei/s), common grackles (Quiscalus quiscula), brown-headed cowbirds (Molothrus ater), and juvenile European starlings (Sturnus vulgaris) feeding on ears of corn was studied in an aviary. The species differed significantly in their propensity to attack (penetrate the husk and feed on kernels) ears of corn. Redwings and starlings were more active attackers than grackles and cowbirds. Female redwings were generally more active attackers than males, but less efficient at opening husks and damaging ears. Redwings and starlings used primarily the gaping technique to penetrate husks and expose kernels. Redwings more commonly penetrated the side of …


Effect Of Pre-Burn Artificial Litter And Prescribed Burning On Smooth Brome (Bromus Inermis Leyss), Patricia R. Boehner Aug 1986

Effect Of Pre-Burn Artificial Litter And Prescribed Burning On Smooth Brome (Bromus Inermis Leyss), Patricia R. Boehner

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


As Assessment Of The Fisheries Research Program Of The National Marine Fisheries Service, Gary Page Bulmer May 1986

As Assessment Of The Fisheries Research Program Of The National Marine Fisheries Service, Gary Page Bulmer

Marine Affairs Theses and Major Papers

The nation's fishery management regime has three primary sets of players: the scientific advisors, the managers, and the fishermen. The advisors include federal agencies, state agencies, universities, regional and interstate bodies, and international bodies. The National Marie Fisheries Service (NMFS) has the lead role as scientific advisor. As used here "management" is defined broadly to include the instructions and funding that the researchers are given. "Fisheries research" is also defined broadly for the purposes of this paper. It means the collection of any biological, economic, or social information which is relevant to fisheries management.


Disease Incidence Of Demersal Finfishes From The Southern And Western Branches Of The Elizabeth River, Virginia, Randal D. Owen Apr 1986

Disease Incidence Of Demersal Finfishes From The Southern And Western Branches Of The Elizabeth River, Virginia, Randal D. Owen

Biological Sciences Theses & Dissertations

Fishes from the industrialized environs of the Elizabeth River, Virginia were surveyed for external evidence of disease during June through October 1984. A highly significant (p < 0.001) incidence of disease was found in demersal fishes collected by otter trawl from a site in the industrially contaminated Southern Branch compared to a less contaminated Western Branch site. Cataracts, fin erosion and dermal lesions were the most commonly occurring anomalies in the Southern Branch finfish.

Static, solid-phase toxicity tests employing sediment collected from the Southern Branch site resulted in an immediate toxic stress in the spot, Leiostomus xanthurus, which resulted in 100% mortality within 24 hours, compared with no mortalities in control systems. Spot exposed to control, i.e., pollution free, and diluted Southern Branch sediments innoculated with the pathogenic bacterial species, Vibrio anguillarium, developed significant (p ≤ 0.020) cases of fin erosion at a mean total bacterial community density …


Population Dynamics And Expansion Rates Of Black-Tailed Prairie Dogs, Lyle A. Crosby, Randy Graham Mar 1986

Population Dynamics And Expansion Rates Of Black-Tailed Prairie Dogs, Lyle A. Crosby, Randy Graham

Vertebrate Pest Conference Proceedings: 12th (1986)

The purpose of this review is to describe population dynamics and annual rates of increase of black-tailed prairie dogs (Cynomys ludovicianus) and to determine annual expansion rates of uncontrolled populations. Their reproductive characteristics, including social behavior are examined as they relate to these factors.

In this analysis, the first step is to determine the average number of male and female prairie dogs of breeding age that are present at each burrow system before and after the reproductive cycle. From this determination the total number of prairie dogs is determined, based on the average density of active burrows for …


Population, Migration, And Problems Of Atoll Development In The South Pacific, John Connell Mar 1986

Population, Migration, And Problems Of Atoll Development In The South Pacific, John Connell

Pacific Studies

No abstract provided.


Grazing And Management Of Saltland Shrubs, C V. Malcolm, J. E. Pol Jan 1986

Grazing And Management Of Saltland Shrubs, C V. Malcolm, J. E. Pol

Journal of the Department of Agriculture, Western Australia, Series 4

areas of bare saltland on farms need not be unproductive etesores. Many Western Australian farmers are now successfully growing salt-tolerant or halophytic shrubs such as bluebush (Maireana brevifolia), saltbushes (Atriplex spp.) and samphires (Halosarcia spp.) on these areas.

Department of agriculture trials and farmers' experience indicate that if saltland is planted with recommended shrubs, it can provide two months' valuable grazing for sheep during autumn and early winter, a time when paddock feed is scarce. Research by the Department has also identified a range of salt-tolerant shrubs suited to the various types of saltland.

Grazing trials to …


The Effect Of Dietary Protein And Feed Size On The Assimilation Efficiency Of Starlings And Blackbirds, Daniel J. Twedt Dec 1985

The Effect Of Dietary Protein And Feed Size On The Assimilation Efficiency Of Starlings And Blackbirds, Daniel J. Twedt

Great Plains Wildlife Damage Control Workshop Proceedings

Starlings (Sturnus vulgarisl were fed 3 feed sizes and 3 protein levels of swine feeds to determine metabolizable energy and assimilation efficiency. Metabolizable energy (12 kcal/g of diet consumed) and assimilation efficiency (3296 of gross energy intake) were independent of feed size. A 46% crude protein diet was 5196 assimilated and yielded more energy per gram of diet consumed than a 2196 crude protein diet which was only 35% assimilated. Starlings failed to maintain their body weight on a cracked corn diet containing 14% crude protein. Feeding behaviors of starlings due to their assimilation efficiencies are discussed and contrasted with …


The Effect Of Dietary Protein And Feed Size On The Assimilation Efficiency Of Starlings And Blackbirds, Daniel J. Twedt Dec 1985

The Effect Of Dietary Protein And Feed Size On The Assimilation Efficiency Of Starlings And Blackbirds, Daniel J. Twedt

Great Plains Wildlife Damage Control Workshop Proceedings

Starlings (Sturnus vulgaris) were fed 3 feed sizes and 3 protein levels of swine feeds to determine metabolizable energy and assimilation efficiency. Metabolizable energy (12 kcal/g of diet consumed) and assimilation efficiency (3296 of gross energy intake) were independent of feed size. A 46% crude protein diet was 5196 assimilated and yielded more energy per gram of diet consumed than a 2196 crude protein diet which was only 35% assimilated. Starlings failed to maintain their body weight on a cracked corn diet containing 14% crude protein. Feeding behaviors of starlings due to their assimilation efficiencies are discussed and contrasted with …


Mathematical Programming Model Of Western Australian Dairy Farms, G R. Olney, D A. Falconer Nov 1985

Mathematical Programming Model Of Western Australian Dairy Farms, G R. Olney, D A. Falconer

Animal production and livestock research reports

A profit maximising mathematical programming dairy farm model has been developed which determines the most profitable management strategies for the full year. This model was initially an extension of the one used in the Western Australian Dairy Feed Management Service (DFMS) which determines the most profitable ration to feed for a specific period, the milk yield per cow and the number of cows to milk. The DFMS is useful for formulating a ration for a specific period, particularly during summer on non-irrigated farms in Western Australia when complete hand feeding is required, but it cannot be used to determine optimum …


Multiple Trophic Levels In Soft-Bottom Communities, John A. Commito, William G. Ambrose Jr. Oct 1985

Multiple Trophic Levels In Soft-Bottom Communities, John A. Commito, William G. Ambrose Jr.

Environmental Studies Faculty Publications

In order to assess the general applicability of recent field experiments with predatory infauna, we searched the literature and found 48 well-documented cases of infaunal consumption by such predators. In 63 % of the cases detailed enough to make a determination, the predators ate other predators. Multiple trophic levels within the infauna are probably a common feature of many soft-bottom communities.


Somalia Fisheries Development: Past, Present And Future, Bruce Barbour Oct 1985

Somalia Fisheries Development: Past, Present And Future, Bruce Barbour

Marine Affairs Theses and Major Papers

This paper is being presented in three distinct parts. Each section deals with fisheries development in Somalia, East Africa, past, present and future. The first section focuses on a project proposal by a World Bank/U.N. FAO joint effort. This proposal exemplifies a traditional approach to development. This traditional approach will be defined and then evaluated. The second section is a report of the authors consultancy to the Somali government concerning the development of the fisheries within the Coastal Development Projects jurisdiction. The approach employed was one of first defining the problem and then working on solutions. This section is being …