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13.4.4. Habitat Management For Molting Waterfowl, James K. Ringelman Jan 1990

13.4.4. Habitat Management For Molting Waterfowl, James K. Ringelman

Waterfowl Management Handbook

The ecology, behavior, and life history strategies of waterfowl are inseparably linked to that unique avian attribute, feathers. Waterfowl rely on flight capabilities to migrate, to fully exploit the resources of wetland and upland communities, and to escape life-threatening events. The insulation provided by contour and down feathers allows waterfowl to use a wide range of habitats and protects them from temperature extremes. Plumage is important not only for species recognition during courtship, but also for cryptic coloration of females during incubation. However, feathers become worn and must be periodically replaced. The process of feather renewal, or molt, is a …


13.1.2 Life History Traits And Management Of The Gadwall, James K. Ringelman Jan 1990

13.1.2 Life History Traits And Management Of The Gadwall, James K. Ringelman

Waterfowl Management Handbook

The gadwall is widely distributed throughout the western two-thirds of North America. Although its primary breeding habitat is in the drought-prone and degraded waterfowl habitats of the northern Great Plains, its continental population has remained relatively stable while those of most other dabbling ducks have declined. Some unique life history traits may in part be responsible for the resilience of gadwall populations. These unique attributes, which are important for gadwall management, are the subject of this leaflet. Readers interested in general references on gadwall biology and natural history are referred to Bellrose (1980) or Palmer (1976).


An Introduction To The Soils Of The Jerramungup Advisory District, T C. Stoneman, National Soil Conservation Program (Australia) Jan 1990

An Introduction To The Soils Of The Jerramungup Advisory District, T C. Stoneman, National Soil Conservation Program (Australia)

Bulletins 4000 -

With descriptions, illustrations and notes on eight common soils.


A Recycling Proposal For The Vashon Island School District, John Turner Green Jan 1990

A Recycling Proposal For The Vashon Island School District, John Turner Green

All Graduate Projects

The purpose of this study was to identify a process by which the Vashon Island School District could reduce its waste stream and involve and educate students in an environmental ethic that actively seeks to reduce and recycle wastes. A search of the general and educational literature was made. An extensive research of state and local agencies helped to identify appropriate goals and actions for the Vashon School District. The proposal calls for seven specific actions to be taken.


Plantscan, Ted Lefroy, Fritz Droge Jan 1990

Plantscan, Ted Lefroy, Fritz Droge

Natural resources published reports

PLANTSCAN is a network of schools and landholders throughout the wheatbelt of Western Australia. It aims to speed up the process of testing plants for their suitability to this environment.

This kit contains seed of various trees and shrubs and notes on how to grow them, plant them out into a small plot and record their progress.

Schools and landholders throughout the wheatbelt who have purchased this kit become part of a research network aimed at selecting plants that will:

* overcome soil erosion;

* overcome soil salinity;

* and provide a source of income for farmers.

The following sheets …


The Probe, Issue 98 - December 1989 Dec 1989

The Probe, Issue 98 - December 1989

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE National Animal Damage Control Association
DECEMBER 1989
Vote
NADCA Elections
NADCA Annual Meeting
Letters to Ye Ed
APHIS Activity Report
Animal Rights


Frequency-Dependent Seed Dispersal By Ants Of Two Deciduous Forest Herbs, Brent H. Smith, Catherine E. De Rivera, Cara Lin Bridgman, John J. Woid Dec 1989

Frequency-Dependent Seed Dispersal By Ants Of Two Deciduous Forest Herbs, Brent H. Smith, Catherine E. De Rivera, Cara Lin Bridgman, John J. Woid

Environmental Science and Management Faculty Publications and Presentations

Two co—occurring deciduous forest myrmecochores, Asarum canadense and Jeffersonia diphylla, release their seeds at approximately the same time, and therefore potentially compete for ants as dispersers. Within a single woodlot, we placed seeds of both species inside a dense Jeffersonia population away from Asarum plants, inside a dense Asarum population away from Jeffersonia plants, and in a site where plants of neither species occurred. No preference was exhibited by ants where natural populations were absent. Preference at the other two sites was frequency dependent: ants preferred seeds of the introduced species. Species preferred by ants have higher seed and …


Water Conservation Through Irrigation Technology, Donald H. Negri, John J. Hanchar, United States Department Of Agriculture, Economic Research Service Nov 1989

Water Conservation Through Irrigation Technology, Donald H. Negri, John J. Hanchar, United States Department Of Agriculture, Economic Research Service

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

Improved irrigation technology and advanced farm management practices offer an opportunity for agriculture to use water more efficiently. Farmers may install new equipment, such as drip irrigation systems, or adopt advanced water management practices to conserve water without sacrificing crop yields. While farmers' decision to adopt water-saving irrigation technology responds to the cost of water, physical properties of the land such as topography or soil properties of the land such as topography or soil texture dominate the choice of irrigation technology.


Population Dynamics And Management Of Deer In Wisconsin, Keith R. Mccaffery Sep 1989

Population Dynamics And Management Of Deer In Wisconsin, Keith R. Mccaffery

Wildlife Damage Management Conference

Management of deer in Wisconsin is affected by a combination of biological and environmental factors. In the Northern Forest, winter severity dramatically affects annual survival and recruitment. However, deer density goals here are above "I" carrying capacity. Thus, minor errors in harvest management are in part compensated by herd responses. Deer in the farmland areas of the state are maintained at goals that for the most part are below "I" carrying capacity. Errors in harvest management are magnified in farmland because herd responses are not compensatory. Therefore, the harvest quotas for antlerless deer must be more precise in our farmland …


Fertility Control As A Tool For Regulation Of Wildlife Populations, U. S. Seal Sep 1989

Fertility Control As A Tool For Regulation Of Wildlife Populations, U. S. Seal

Wildlife Damage Management Conference

Biological control of reproduction and fertility is a normal part of the life history of all organisms. Control mechanisms allow timing of reproduction with respect to age, time of day, season, and other periodic environmental events. Further modulation can occur with variations in temperature, rainfall, nutrition, and health status. Interactions with other members of the species, ranging from pherohormonal stimulation of estrus to social delay of puberty and breeding to infanticide, provide further constraints upon fertility and recruitment. All of these processes ultimately act through molecular neuroendocrine mechanisms that are under genetic control and are subject to natural selection and …


Population Dynamics And Management Of Deer In Wisconsin, Keith R. Mccaffery Sep 1989

Population Dynamics And Management Of Deer In Wisconsin, Keith R. Mccaffery

Eastern Wildlife Damage Control Conference: 4th (1989)

Management of deer in Wisconsin is affected by a combination of biological and environmental factors. In the Northern Forest, winter severity dramatically affects annual survival and recruitment. However, deer density goals here are above "I" carrying capacity. Thus, minor errors in harvest management are in part compensated by herd responses. Deer in the farmland areas of the state are maintained at goals that for the most part are below "I" carrying capacity. Errors in harvest management are magnified in farmland because herd responses are not compensatory. Therefore, the harvest quotas for antlerless deer must be more precise in our farmland …


Fertility Control As A Tool For Regulation Of Wildlife Populations, U.S. Seal Sep 1989

Fertility Control As A Tool For Regulation Of Wildlife Populations, U.S. Seal

Eastern Wildlife Damage Control Conference: 4th (1989)

Biological control of reproduction and fertility is a normal part of the life history of all organisms. Control mechanisms allow timing of reproduction with respect to age, time of day, season, and other periodic environmental events. Further modulation can occur with variations in temperature, rainfall, nutrition, and health status. Interactions with other members of the species, ranging from pherohormonal stimulation of estrus to social delay of puberty and breeding to infanticide, provide further constraints upon fertility and recruitment. All of these processes ultimately act through molecular neuroendocrine mechanisms that are under genetic control and are subject to natural selection and …


An Analysis Of The Water Situation In The United States: 1989-2040, Richard W. Guldin, Usda Forest Service Sep 1989

An Analysis Of The Water Situation In The United States: 1989-2040, Richard W. Guldin, Usda Forest Service

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

Several Federal agencies have historically had responsibilities for conducting assessments of the Nation's water resources. The U.S. Geological Survey (USGS), U.S. Army Corps of Engineers, U.S. Department of Agriculture's Soil Conservation Service (SCS), and U.S. Environmental Protection Agency (EPA) and its predecessor agencies, among others, have conducted studies assessing the current situation and future prospects for water in particular regions of the country. Responsibility for national water assessments was assigned to the U.S. Water Resources Council (WRC) by the Water Resources Planning Act of 1965. With the demise of the WRC in 1981, several member agencies have attempted to take …


Biological Reductive Dechlorination Of Tetrachloroethylene And Trichloroethylene To Ethylene Under Methanogenic Conditions, David L. Freedman, James M. Gossett Sep 1989

Biological Reductive Dechlorination Of Tetrachloroethylene And Trichloroethylene To Ethylene Under Methanogenic Conditions, David L. Freedman, James M. Gossett

Publications

A biological process for remediation of groundwater contaminated with tetrachloroethylene (PCE) and trichloroethylene (TCE) can only be applied if the transformation products are environmentally acceptable. Studies with enrichment cultures of PCE- and TCE-degrading microorganisms provide evidence that, under methanogenic conditions, mixed cultures are able to completely dechlorinate PCE and TCE to ethylene, a product which is environmentally acceptable. Radiotracer studies with [14C]PCE indicated that [14C]ethylene was the terminal product; significant conversion to 14CO2 or 14CH4 was not observed. The rate-limiting step in the pathway appeared to be conversion of vinyl chloride to ethylene. To sustain reductive dechlorination of PCE and …


Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle Jun 1989

Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle

Publications (WR)

Temporal and spatial patterns of age 0 threadfin shad (Dorosoma petenense) abundance and growth, in the Overton Arm of Lake Mead, were examined to evaluate the effects of resource availability on the young fish. This was part of a larger, game fishery enhancement study (Lake Mead Fertilization Project), designed to assess feasability of increasing survivorship of larval/juvenile shad by boosting phosphate levels, thereby increasing algal and zooplankton biomass, during the shad spawning period. Shad are the primary forage base for the striped bass (Morone saxatilis) and black bass (Macropterus salmoides) fisheries. Weekly samples were …


Determination Of Trace Amounts Of Lead, Cadium And Zinc In Vegetables Using Differential Pulse Polarography, Elizabeth Franca-Romitti May 1989

Determination Of Trace Amounts Of Lead, Cadium And Zinc In Vegetables Using Differential Pulse Polarography, Elizabeth Franca-Romitti

Theses

Toxic metals are present in foods to greater or lesser extention as contaminants, as a result of increasing industrialization, and associated pollution of the biosphere. Lead and cadmium are well known toxic metals which accumulate into the body causing harmful effects at low concentration levels especially in children. Zinc, on the other hand, is an essential micronutrient, but larger levels in foods can be considered toxic.

Twenty eight brands of vegetables including canned, glass packed, frozen and fresh vegetables were analyzed for Pb, Cd, and Zn, in tomatoes, carrots, mushrooms and asparagus. The technique used was Differential Pulse Polarography (DPP) …


Characterization Of Activated Sludge Immobilized In Calcium Alginate Gel With Respect To Biodegradation Of 2-Chlorophenol And Benzene, Manjari Singh May 1989

Characterization Of Activated Sludge Immobilized In Calcium Alginate Gel With Respect To Biodegradation Of 2-Chlorophenol And Benzene, Manjari Singh

Theses

Activated sludges acclimated with phenol and 2-chlorophenol in one case, and a mixture of benzene, toluene, and o, in and p-xylene in another case, were characterized for biodegradation of 2-chlorophenol and benzene, respectively. Activated sludge was obtained from the Parsippany-Troy Hills Water Pollution Control Plant (NJ).

For both cases colonies were isolated before acclimation, after acclimation, and at the end of biodegradation studies. Since the unacclimated group was the same in both cases, there were a total of five different groups for which characterization was carried out.

For all the five groups together, a total of 54 isolates were obtained …


Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson May 1989

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 …


Management, Foraging Behavior, Diet Composition And Forage Quality Of Free-Ranging But Herded Camels In Ceeldheer District, Central Somalia, Ahmed A. Elmi May 1989

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, …


Jim Bindon's Review Of Tsuguyoshi Suzuki And Ryutaro Ohtsuka's Human Ecology Of Health And Survival In Asia And The South Pacific, Jim Bindon Mar 1989

Jim Bindon's Review Of Tsuguyoshi Suzuki And Ryutaro Ohtsuka's Human Ecology Of Health And Survival In Asia And The South Pacific, Jim Bindon

Pacific Studies

No abstract provided.


Black-Footed Ferret Recovery, Dean E. Biggins, Ronald A. Crew Feb 1989

Black-Footed Ferret Recovery, Dean E. Biggins, Ronald A. Crew

Great Plains Wildlife Damage Control Workshop Proceedings

The captive population of black-footed ferrets increased from 24 to 58 animals in 1988, and was split to provide the species added protection against extinction. Experimental reintroductions may begin in 1991. In some areas, "experimental population" designations as authorized under Section 10 (j) of the Endangered Species Act may be used to provide wider management latitude. The Black-footed Ferret Interstate Coordinating Committee oversees much of the work related to reintroduction. Expanded effort to locate wild ferrets now includes a $10,000 reward offer. Research focuses on captive breeding, reintroduction techniques, disease, and habitat. A new Recovery Plan was approved in 1988.


Urban Nuisance Wildlife Problems In Arizona, Rebecca L. Wright, Leonard L. Ordway Feb 1989

Urban Nuisance Wildlife Problems In Arizona, Rebecca L. Wright, Leonard L. Ordway

Great Plains Wildlife Damage Control Workshop Proceedings

Arizona has experienced an increase in urbanization of wildlife habitat, which has led to an urban nuisance wildlife problem. The Arizona Game and Fish Department is working to lessen the problem through public education, information packets and use of private pest control companies to remove wildlife for a fee.


Management Problems Encountered With Livestock Guarding Dogs On The University Of California, Hopland Field Station, Robert M. Timm, Robert H. Schmidtz Feb 1989

Management Problems Encountered With Livestock Guarding Dogs On The University Of California, Hopland Field Station, Robert M. Timm, Robert H. Schmidtz

Great Plains Wildlife Damage Control Workshop Proceedings

Guard dogs are being promoted and utilized as effective predator damage control tools under a variety of livestock management conditions. We report our experience over 1 1/2 years with 5 dogs, primarily Anatolian shepherd and Akbash dog breeds. We discuss a number of behavioral and management problems we have encountered, some of which have not previously been reported in the literature. These include chasing vehicles and wildlife, predation on deer (Odocoileus hemionus columbianus), and incompatibility of dogs with other predator damage control methods.


Biochemical And Morphological Characteristics In Maturing Achenes From Purple-Hulled And Oilseed Sunflower Cultivars, Roger W. Bullard, Paul P. Woronecki, Richard A. Dolbeer, J. Russell Mason Jan 1989

Biochemical And Morphological Characteristics In Maturing Achenes From Purple-Hulled And Oilseed Sunflower Cultivars, Roger W. Bullard, Paul P. Woronecki, Richard A. Dolbeer, J. Russell Mason

United States Department of Agriculture Wildlife Services: Staff Publications

The blackbird feeding preference for sunflower oilseed variety Jacques Discovery (JD) over purple-hulled Neagra de Cluj (NdC) has been attributed to anthocyanin. To test this hypothesis, we compared biochemical and morphological properties in the achene over the maturation period. Comparisons included total phenols, anthocyanin, tannin, fat/oil, protein, nonstructural sugars, and phytomelanin contents, as well as mass properties and moisture content. Only three differences were observed: (1) Hull mass was significantly higher for NdC than JD. (2) Anthocyanins were synthesized by NdC only. (3) JD was higher in oil content. Each of these factors may play a role in reduced preferences …


Formulation Of A Management Scheme For The Swordfish Fishery Of The Eastern Caribbean, Harold F. Upton Jan 1989

Formulation Of A Management Scheme For The Swordfish Fishery Of The Eastern Caribbean, Harold F. Upton

Marine Affairs Theses and Major Papers

During the 1983 season, two U.S. longline vessels initiated the first attempts at the commercial exploitation of swordfish in the Eastern Caribbean. In 1986, the number of U.S. vessels participating in the fishery surpassed 40 with landings of nearly two million pounds per season. The sudden influx of participants and technology to the region has resulted in a variety of user conflicts and associated policy issues. Major areas of concern involve the conservation of a heavily exploited resource and the distribution of benefits which accrue from resource exploitation among the resource-adjacent island states and U.S. fishing operations. This study examines …


Erosion Potential Of Phomopsis-Resistant Lupins, D J. Carter, Paul Findlater Jan 1989

Erosion Potential Of Phomopsis-Resistant Lupins, D J. Carter, Paul Findlater

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

During lupin harvesting, up to 20 per cent of the grain remains on the ground. This non-harvested or pilt grain is a valuable feed for sheep during early summer because the pods, leaf and stem generally provide little nutrient in the stubnbles. In addition, the more efficient the weed control, the less valuable are the stubbles.

The disease lupinosis caused by Phomopsis leptostromiformis restricts the amount of grazing from the lupin stubbles, and hence the risk of wind-erosion of stubble paddocks.

However, the introduction of lupin varieties moderately resistant to Phomopsis and with reduced potential to cause lupinosis means that …


Estimates Of Macroinvertebrate Biomass In Lake Michigan, Thomas F. Nalepa Jan 1989

Estimates Of Macroinvertebrate Biomass In Lake Michigan, Thomas F. Nalepa

United States Department of Commerce: Staff Publications

To obtain updated, more accurate estimates of macroinvertebrate standing stocks in Lake Michigan, benthic biomass (ash-free dry weight) was determined at 40 stations in the southern end of the lake in 1980 and 1981. Biomass generally increased as sampling depth increased from 16 to 30 m, peaked at depths of 30-40 m, and then declined at depths greater than 40 m. Mean total biomass at the 16-30 m, 31-50 m, 51-90, and> 90 m depth intervals was 4.9, 7.8, 4.2, and 1.9 g m-2, respectively. Oligochaetes (46%) and Pontoporeia hoyi (44%) accounted for most of the biomass at …


13.2.5. Avian Cholera: A Major New Cause Of Waterfowl Mortality, Milton Friend Jan 1989

13.2.5. Avian Cholera: A Major New Cause Of Waterfowl Mortality, Milton Friend

Waterfowl Management Handbook

Avian cholera is a highly infectious disease caused by the bacterium, Pasteurella multocida. Acute infections are common and can result in death 6 to 12 hours after exposure. Under these circumstances “explosive” die-offs involving more than 1,000 birds per day have occurred in wild waterfowl. More chronic infections with longer incubation times and less dramatic losses also occur. Transmission can occur by bird-to-bird contact, ingestion of contaminated food or water, and perhaps in aerosol form.


13.2.6. Lead Poisoning: The Invisible Disease, Milton Friend Jan 1989

13.2.6. Lead Poisoning: The Invisible Disease, Milton Friend

Waterfowl Management Handbook

Lead poisoning is an intoxication resulting from absorption of hazardous levels of lead into body tissues. Lead pellets from shot shells, when ingested, are the most common source of lead poisoning in migratory birds. Other far less common sources include lead fishing sinkers, mine wastes, paint pigments, bullets, and other lead objects that are swallowed.


13.4.12. Control Of Phragmites Or Common Reed, Diana H. Cross, Karen L. Fleming Jan 1989

13.4.12. Control Of Phragmites Or Common Reed, Diana H. Cross, Karen L. Fleming

Waterfowl Management Handbook

Phragmites, or common reed, is a perennial grass often associated with wetlands. When phragmites is interspersed with open water or with other vegetation, waterbirds and small mammals find cover among the stems. Its dense root systems strengthen dikes and roads. On many sites, however, this robust emergent forms monotypic, impenetrable stands having little value for waterfowl. Ducks occasionally nest on the edges of large stands, but avoid the dense interior.

Phragmites is native to North America and is found worldwide, primarily in lowland temperate regions. Phragmites can occupy upland sites with seeps, or grow in brackish or fresh water several …