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Diets Of The Red-Billed Quelea (Quelea Quelea) In The Awash River Basin Of Ethiopia, W. A. Erickson Nov 1979

Diets Of The Red-Billed Quelea (Quelea Quelea) In The Awash River Basin Of Ethiopia, W. A. Erickson

Bird Control Seminars Proceedings

An understanding of the feeding ecology of the red-billed quelea (Quelea quelea) is necessary for a comprehensive assessment of the potential impact of this species on cereals development. Queleas are reported to subsist primarily on wild Gramineae (Ward 1965a; Gaston 1976), but their mobility and tendency to feed in large aggregations readily adapts them to becoming a major cereal crop pest (Dyer & Ward 1977). Currently, conflicting evidence exists as to the factors involved in attacks on cereals and the relationship of depredation to the availability of wild foods. In Nigeria, Ward’s (1965a) findings indicated queleas prefer small wild grass …


State Of The Fisheries Report 1978, Department Of Fisheries And Wildlife, Western Australia Sep 1979

State Of The Fisheries Report 1978, Department Of Fisheries And Wildlife, Western Australia

Status Reports of the Fisheries and Aquatic Resources

Western Australia has maintained its position as the top fishing State. The catch in Western Australia of fish, crustaceans, and molluscs in 1977-78 was worth $76 million to the fishermen, which is 36 per cent of the total value for Australia.


Ecotypic Differentiation Of Andropogon Virginicus L. In Relation To Strip Mine Spoil Banks, Valina Kay Hurt May 1979

Ecotypic Differentiation Of Andropogon Virginicus L. In Relation To Strip Mine Spoil Banks, Valina Kay Hurt

Masters Theses & Specialist Projects

Reciprocal plantings of populations of broomsedge, taken from an abandoned strip mine and from an abandoned farm plot in south central Kentucky, on strip mine spoil and abandoned field soil resulted in patterns of populations differentiation. Clonal plantings of populations from strip mine habitats and old field development appeared equal in height and biomass when grown on old field soils in both field trials and growth chamber studies. Populations when planted in strip mine soils in field trials and controlled growth experiments. Later flowering in strip mine populations may be a key to survival strategy in the harsh microclimates of …


Development And Validation Test Of A Mule Deer Habitat Rule, Glenn Gephart May 1979

Development And Validation Test Of A Mule Deer Habitat Rule, Glenn Gephart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mathematical description of Rocky Mountain mule deer (Odocoileus hemionus hemionus) habitat was developed and subjected to validation testing using correlation and multiple regression statistical techniques. Data were collected on a central Utah study area, which was divided into mountain and desert regions.

Data on deer utilization and several habitat components from 86 study plots visited in 1976 were used to develop a habitat rule. Data from 46 study plots visited in 1977 were used to test the accuracy of the rule. Deer utilization was determined from pellet group counts on 20 0.001 ha pellet plots at each …


Some Effects Of A Grazer, Hyalella Azteca On Ecosystem Level Properties In Aquatic Microcosms, Martin D. Werner May 1979

Some Effects Of A Grazer, Hyalella Azteca On Ecosystem Level Properties In Aquatic Microcosms, Martin D. Werner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study to determine some ecosystem level effects of an aquatic invertebrate grazer, Hyalella azteca, was performed in aquatic ix microcosms. Impact of the grazer was assessed in three general areas: 1) inorganic nutrient levels of the microcosm water column, 2) productivity and respiration of the biotic community, and 3) plant community composition in the microcosms.

The grazing amphipod caused inorganic phosphorus and nitrogen (except ammonia) levels to be elevated in the microcosms. The increase was due, at least partially, to excretion of nutrients into the water by the amphipod. The presence of H. azteca did not significantly …


Effects Of Forage Availability On Voluntary Intake And Feeding Behavior Of Grazing Heifers, Anastasios S. Nastis May 1979

Effects Of Forage Availability On Voluntary Intake And Feeding Behavior Of Grazing Heifers, Anastasios S. Nastis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forage intake by animals is an important factor in determining production of livestock products from rangelands. However, relatively little is known of effects of such forage variables as availability and distribution in space upon intake. Even less is known about how the grazing animal modifies its feeding tactics when confronted with diminishing or limited supplies of available forage and how such altered behavior may affect the animal's energetic cost for existence. Forage intake, body weight gain, grazing time and biting rate of Angus heifers was related to forage availability and plant height on semiarid crested wheatgrass rangeland during the late …


Management Of Antarctic Krill, Paul Setliff Jan 1979

Management Of Antarctic Krill, Paul Setliff

Marine Affairs Theses and Major Papers

This study pertains to the problem of international activity in an area of political and ecological sensitivity, the Southern Ocean. Of specific concern is the question of which group of states should have a voice in management of Antarctic krill. The niche filled by krill within the ecosystem and its potential as a fishery is discussed. Past international practice has been affected for the most part by the Antarctic Treaty of 1959 which has maintained a somewhat exclusive "club" of nations as the overseers of Antarctic activity. However, states not party to the 1959 Treaty are becoming interested in the …


Impact Of Water And Soils Having High Source-Sink Potentials On Water And Salinity Management Under Irrigation In The Upper Colorado River Basin, Lyman S. Willardson, R. J. Hanks, J. J. Jurinak Jan 1979

Impact Of Water And Soils Having High Source-Sink Potentials On Water And Salinity Management Under Irrigation In The Upper Colorado River Basin, Lyman S. Willardson, R. J. Hanks, J. J. Jurinak

Reports

Water management in irrigation projects is one potential method for reducing downstream salinity in the Colorado River. An important contribution can be made to developing more effective irrigation water management practices for water conservation and salinity control through identification and better understanding of the soil and water interactions that result in soils behaving as salt sources or as salt sinks. The interactions identified in this study were examined to determine the effects of various management alternatives on the quality and quantity of salt in subsurface return flow from irrigation projects. A soil solution chemistry model was developed to describe the …


Nitrogen Cycling In Great Basin Desert Soils, J. Skujins, B. Klubek Jan 1979

Nitrogen Cycling In Great Basin Desert Soils, J. Skujins, B. Klubek

Memorandum

No abstract provided.


Demography Of Termite Colonies As Related To Various Environmental Factors: Nutritional Biochemistry And Physiology Of Termites, W. L. Nutting, J. P. Lafage Jan 1979

Demography Of Termite Colonies As Related To Various Environmental Factors: Nutritional Biochemistry And Physiology Of Termites, W. L. Nutting, J. P. Lafage

Memorandum

No abstract provided.


Demography Of Termite Colonies As Related To Various Environmental Factors: Nutritional Biochemistry And Physiology Of Termites, W. L. Nutting, J. P. Lafage Jan 1979

Demography Of Termite Colonies As Related To Various Environmental Factors: Nutritional Biochemistry And Physiology Of Termites, W. L. Nutting, J. P. Lafage

Memorandum

No abstract provided.


Managing Water-Repellent Soils, D A. Mcghie Jan 1979

Managing Water-Repellent Soils, D A. Mcghie

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

A study of water-repellent soils has led to some management recommendations.


The Distribution Of Cadmium, Chromium And Lead In Crabs, Clams And Oysters From Calcasieu Estuary, Louisiana, Fritz Jaenike Jan 1979

The Distribution Of Cadmium, Chromium And Lead In Crabs, Clams And Oysters From Calcasieu Estuary, Louisiana, Fritz Jaenike

Masters Theses

In November 1978, specimens of oysters (Crassostrea virginica), clams (Rangia cuneata), crabs (Callinectes sapidus) and water and sediment samples were collected from Calcasieu Estuary, Louisiana. The concentrations of cadmium, chromium and lead were determined in the samples with an inductively coupled argon plasma direct reading emission spectrophotometer. Crab claw muscle, gill and carapace tissues were analyzed separately. Oysters and clams were separated into shell and whole soft tissue samples which were analyzed separately. The concentration order of the metals in crab carapace and in oyster shells was similar to that of the sediments, (Pb …


Catfish Cage Culture In A South Dakota Power Plant Cooling Reservoir, Gary P. Wheeler Jan 1979

Catfish Cage Culture In A South Dakota Power Plant Cooling Reservoir, Gary P. Wheeler

Electronic Theses and Dissertations

Studies were conducted to evaluate the Big Stone Power Plant cooling reservoir in northeastern South Dakota as a site for cage culturing channel catfish (Ictalurus punctatus) for market and sport fishery stocking. Temperatures suitable for catfish culture (21-32 C) were present in the reservoir from mid-March through mid-September 1978 and from mid-October through 4 November 1978, the end of the study period. Mean values of chemical parameters analyzed included dissolved oxygen - 8.8 mg/1, total available chlorine- 0.13 mg/1, pH - 8.6, specific conductance - 2228 micromhos/cm, total hardness - 1128 mg/1 as CaC03, calcium hardness - 570 mg/1 as …


Effects Of Oil Shale Leachate On Phytoplankton Productivity, Mary Louise Cleave, V. Dean Adams, Donald B. Porcella Jan 1979

Effects Of Oil Shale Leachate On Phytoplankton Productivity, Mary Louise Cleave, V. Dean Adams, Donald B. Porcella

Reports

The effects of oil shale leachate and salinity additions on the productivity of freshwater algae were studied in the laboratory using batch bioassays. These batch bioassays were used to screen variations of ten salts in single and multiple additions of all possible combinations of the ten salts; water extractions of different processed and unprocessed oil shales; and the concentration effects of both the salts from 0.3 N to 0.05 N as NaCl and the oil shale extractions on the growth of standard test algae and indigenous algae from Lake Powell. The batch bottle bioassays were conducted following the standard algal …


Economic Feasibility Of Ethanol, Methanol And Alcohol-Gasoline Blends As Alternatives To Gasoline As Motor Fuels, Marjorie Diane Pettypool Jan 1979

Economic Feasibility Of Ethanol, Methanol And Alcohol-Gasoline Blends As Alternatives To Gasoline As Motor Fuels, Marjorie Diane Pettypool

Masters Theses

The major emphasis of this study is the economic feasibility of the use of alcohol-gasoline blends (gasohol) and alcohol fuels; but all major issues concerning the use of gasohol and alcohol fuels are explored. The specific objectives of the investigation include the determination of the specific performance properties of the fuels, their pollutant emissions (compared to gasoline), and their costs compared to gasoline.

While opponents to the use of alcohol fuels are more vocal than proponents, citing high cost and the lack of raw materials as objections, proponents believe new processes that can use any cellulose containing material as a …


Analysis Of Lead In Freshwater Clams From The Embarrass River, Coles County, Illinois, Kwaku D. Nantwi Jan 1979

Analysis Of Lead In Freshwater Clams From The Embarrass River, Coles County, Illinois, Kwaku D. Nantwi

Masters Theses

Twenty-two freshwater clams of various genera were collected by hand from two sites on the Embarrass River located at 240 meters and 400 meters downstream from the dam at Lake Charleston and at depths of .4 and 2.5 meters. Ten grams of gill tissue from each clam was prepared by furnace ashing, dissolved in 30 ml. of acid mixture and analyzed for lead content using an atomic absorption spectrometer. The average lead concentration for the clams was 3.60 ppm, while that of the ambient water was 0.33 ppm indicating that these local bivalves show a lead biocentration of about ten …


The Effects Of Heavy Metals On Algae Populations In A South Central Reservoir, Richard L. Meyer Aug 1978

The Effects Of Heavy Metals On Algae Populations In A South Central Reservoir, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

The present investigation examines seasonal variations of algal assemblages in a south-central reservoir, Lake Fayetteville, Arkansas, in an attempt to evaluate the role of various trace metals in relation to these seasonal variations. Iron, manganese, cobalt, copper, lead and zinc concentrations were evaluated for the period of one year from March, 1976 to March, 1977 with concomitant examination of alga] assemblages. In addition to collection of this material, correlations between specific taxa and metals in the water fraction have been evaluated. A detailed literature review dealing with the role of micronutrients in various algal groups has been discussed by Rice …


The Dietary Effects Of Rana Catesbeiana Larvae On Micropterus Salmoides, Eric Jon Evenson Aug 1978

The Dietary Effects Of Rana Catesbeiana Larvae On Micropterus Salmoides, Eric Jon Evenson

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

No abstract provided.


Present Trends In The Development Of Marine Fisheries By Coastal States Of The East Central Atlantic, Ethman T. A. Golley-Morgan May 1978

Present Trends In The Development Of Marine Fisheries By Coastal States Of The East Central Atlantic, Ethman T. A. Golley-Morgan

Marine Affairs Theses and Major Papers

In order to create an incentive for a rapid development of the rural-based artisanal fisheries of coastal states, that can actively compete with large scale industrial fisheries of non-coastal states as well as coastal states of the region, some states are now moving towards an integrated approach in their development efforts. Such integrated projects will take into consideration rural development, provision of infrastructural facilities for fish handling and processing, vessel servicing, repairs and boat building. Socio-economic factors such as organization of fishermen's cooperatives, financing and marketing institutions are also vital inputs.


Movements And Activity Patterns Of The Plains Pocket Gopher (Geomys Bursarius) In Nebraska, Dallas Virchow May 1978

Movements And Activity Patterns Of The Plains Pocket Gopher (Geomys Bursarius) In Nebraska, Dallas Virchow

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

No abstract provided.


Control Of Ground Squirrels In California Using Anticoagulant Treated Baits, Dell O. Clark Mar 1978

Control Of Ground Squirrels In California Using Anticoagulant Treated Baits, Dell O. Clark

Vertebrate Pest Conference Proceedings: 8th (1978)

Anticoagulant treated grain baits have been used to control vertebrate pest depredations in California for over 30 years. The use of anticoagulant treated baits has increased seven (7) times in the past seven (7) years; the majority for the use of ground squirrel, Spermophilus spp., control. Since 1968-69, an average of 1,747,828 net over 5,700,919 gross acres per year has been treated for ground squirrel control.

Current use patterns for ground squirrel control with anticoagulant treated baits include: (1) Repeated spot baitings, and (2) exposure of bait in bait boxes.

Experimental work and many years of operational field use have …


Vertebrate Pest Control, Where From Here?, Raymond M. Momboisse Mar 1978

Vertebrate Pest Control, Where From Here?, Raymond M. Momboisse

Vertebrate Pest Conference Proceedings: 8th (1978)

The legal and regulatory problems confronting the vertebrate pest control profession have mushroomed in recent years. The causes, the groups responsible and a suggested action plan for meeting the problem is outlined.


Vertebrate Control Chemicals: Current Status Of Registrations, Rebuttable Presumptions Against Registrations, And Effects On Users, Glenn A. Hood Mar 1978

Vertebrate Control Chemicals: Current Status Of Registrations, Rebuttable Presumptions Against Registrations, And Effects On Users, Glenn A. Hood

Vertebrate Pest Conference Proceedings: 8th (1978)

Man's use of chemical pesticides has received much attention in recent years, reflecting or generating public consciousness of our environmental welfare. The establishment of Water Quality Acts, the Toxic Substances Control Act, air pollution standards, and the Environmental Protection Agency (EPA) also exemplify this consciousness which has become a major political force. Although there is some unyielding antagonism against all chemicals used to control pests, there is general agreement that pesticides are necessary for the protection of our health, food, fiber, and habitats. Nevertheless, some pesticides have serious shortcomings, especially toxicity to nontarget organisms and long persistence in the environment. …


Comparison Of Pine Vole Populations In A Maintained And An Abandoned Orchard, S. K. Kukila, A. R. Tipton, R. L. Kirkpatrick Feb 1978

Comparison Of Pine Vole Populations In A Maintained And An Abandoned Orchard, S. K. Kukila, A. R. Tipton, R. L. Kirkpatrick

Eastern Pine and Meadow Vole Symposia

Before more effective and reliable control methods for pine vole populations can be developed, it is essential to increase our knowledge of the pine vole's basic biology and ecology. Former research conducted by Estep et al (1978) and Noffsinger (1976) has demonstrated distinct differences in food habits, physiological condition and reproductive activity of pine voles in active and abandoned orchards. A summary of their findings is presented in Kirkpatrick and Noffsinger (1977). Results from these studies has promoted an interest to more completely define population characteristics of pine voles in these two orchard types. In this manner, it will be …


Producing 20-Month Old Beef Steers Off Annual Pasture, K D. Greathead, D. J. Barker, W. J. Ryan Jan 1978

Producing 20-Month Old Beef Steers Off Annual Pasture, K D. Greathead, D. J. Barker, W. J. Ryan

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

A recent Mt Barker experiment compared two systems of fodder conservation with continuous grazing, using two types of steers, at three stocking rates. Year-round performance, carcass composition, and resulting costs and returns per hectare were assessed.

Production per hectare was greatest from crossbred steers at the intermediate stocking rate with either type of fodder conservation.


Fisheries Report No 35 - Fish And Exploited Crustaceans Of The Swan-Canning Estuary, R C.J. Lenanton Jan 1978

Fisheries Report No 35 - Fish And Exploited Crustaceans Of The Swan-Canning Estuary, R C.J. Lenanton

Fisheries Research Reports

Fishes of the Swan-Canning estuarine system are typical of those found in other lower west coast estuarine systems of Western Australia. Species representing three families of elasmobranchs, several of which are commercially important, twenty families of teleosts, and two families of crustaceans (Table 1) commonly occur in this estuarine system. The many other species which occur less commonly in the Swan- Canning estuary are mostly members of the additional families listed in Table l.

The information contained in this document was made available for use by the authors of the following two publications : -

Forbes and Fitzkardinge (1977) Swan …


A Field Trip Manual Grades Four To Six, Desert Sands Unified School District, Robyn Franklin Jan 1978

A Field Trip Manual Grades Four To Six, Desert Sands Unified School District, Robyn Franklin

Theses Digitization Project

No abstract provided.


Desert Biome Aquatic Program: A Literature Search For Biological And Physical Parameters For Use In Estimation Of Zooplankton Production, J. Anne Holman Jan 1978

Desert Biome Aquatic Program: A Literature Search For Biological And Physical Parameters For Use In Estimation Of Zooplankton Production, J. Anne Holman

Memorandum

No abstract provided.


Diet And Nutrition Of The Pronghorn Antelope, Norman C. Messenger Jan 1978

Diet And Nutrition Of The Pronghorn Antelope, Norman C. Messenger

Electronic Theses and Dissertations

Pronghorn antelope (Antilocapra americana) in northwestern South Dakota consumed at least 32 different plants species. Major forage plants were big sagebrush (Artemisia tridentate), silver sage (A. cana), yellow sweet clover (Meliotus officinalis), gold aster (Chrysopsis villosa), and blue grama (Bouteloua gracilis). Cultivated small grain crops were not a major food source of pronghorn. Differences in diet composition, plant groups, plant groups and time of use and plant group, area, month interaction were significant. Average in vitro digestion of 31 food plants was 51 percent. Mean digestion of grasses was 57 percent, forbs 42 percent, and shrubs 55 percent. Yearling male …