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Articles 3271 - 3300 of 3529
Full-Text Articles in Physical Sciences and Mathematics
Pheasant Nesting And Vegetation Development In Dense Nesting Cover Established Under The South Dakota Pheasant Restoration Program, Emmett J. Keyser Iii
Pheasant Nesting And Vegetation Development In Dense Nesting Cover Established Under The South Dakota Pheasant Restoration Program, Emmett J. Keyser Iii
Electronic Theses and Dissertations
Pheasant (Phasianus colchicus) nest use of dense nesting cover (DNC) established under the Pheasant Restoration Program was evaluated in Beadle, Codington, Tripp, and Walworth Counties in South Dakota from 1978 to 1981. Nest densities and success in DNC plots were compared to those found in roadsides and privately owned alfalfa (Medicago sativa) fields, pastures, and small grain fields. Vegetation density and cover development were monitored on DNC plots. Nest densities were generally greatest in DNC plots followed by roadsides and alfalfa fields. Pastures and small grain fields contained the lowest nest densities. No relationship was detected between nest success and …
Seal Development And Infiltration As Affected By Rainfall Kinetic Energy, Deah Abed Mahamad
Seal Development And Infiltration As Affected By Rainfall Kinetic Energy, Deah Abed Mahamad
Electronic Theses and Dissertations
The infiltration of water into soil has been studied for more than 50 years. Much of the effort has concentrated on obtaining infiltration rate measurements for different soils and on developing equations which describe the resulting data. A portion of the infiltration literature has dealt with the large affect that the development of a surface seal has had on the resulting infiltration measurement of a soil. This surface seal may be more significant in determining the infiltration characteristics of a soil than any other single or perhaps combination of factors. Surface seal development has been linked to both rainfall energy …
Characteristics And Use Of Wild Turkey Roost Sites In Southcentral South Dakota, Randall Allen Craft
Characteristics And Use Of Wild Turkey Roost Sites In Southcentral South Dakota, Randall Allen Craft
Electronic Theses and Dissertations
Ten radio-tagged wild turkeys (Meleagris gallopavo)were monitored to document roost site use and bird movements in the Missouri River breaks complex of southcentral South Dakota during the summer of 1984. Distances between roost sites used by wild turkeys ranged from 0.55 km to 3.09 km. Primary and secondary roost sites were identified. Turkeys used one primary roost site consistently every night during periods ranging from a few days to 2 months, then moved to other primary roost sites. Secondary roost sites were used inconsistently by only a few birds that occupied the roost one night, and did not return on …
Growth, Survival, And Reproductive Success Of Largemouth Bass Stocked With Selected Forage Fishes In South Dakota Ponds, R. Dean Beck
Growth, Survival, And Reproductive Success Of Largemouth Bass Stocked With Selected Forage Fishes In South Dakota Ponds, R. Dean Beck
Electronic Theses and Dissertations
Five fish stocking combinations were evaluated to determine effects of forage availability and geographic location on largemouth bass (Micropterus salmoides) growth, survival, and reproductive success two and three years following stocking. Four forage species stocked with largemouth bass included bluegills (Lepomis macrochirus), black bullheads (Ictalurus melas), golden shiners (Notemigonus crysoleucas), and fathead minnows (Pimephales promelas). A largemouth bass only stocking strategy was also evaluated. Largemouth bass survival two years after stocking in eastern South Dakota ponds averaged 26.5%. Largemouth bass only and largemouth bass-bluegill combinations exhibited the greatest survival rates (31.6% and 28.8%, respectively), while the largemouth bass-black bullhead combination …
Dynamics And Distribution Of Fishes Occupying A South Dakota Power Plant Cooling Reservoir, Timothy R. Walters
Dynamics And Distribution Of Fishes Occupying A South Dakota Power Plant Cooling Reservoir, Timothy R. Walters
Electronic Theses and Dissertations
Distribution, population number, growth rate, and reproductive activities of walleyes (Stizostedion vitreum vitreum) were studied to evaluate the potential of the Big Stone Power Plant cooling reservoir as a source of walleye brood stock. In addition, dynamics and distribution of bluegill (Lepomis macrochirus) and orangespotted sunfish (L. humilis) were examined. Walleye grew well, reaching a weighted mean total length of 271 mm at formation of annulus I. Survival of walleye was poor, with population estimates of 41 and 43 fish in 1984 and 1985, respectively. Low sample size precluded analysis of distribution, but no consistent preference for an area of …
Influence Of Geomorphological Origin Upon Macroinvertebrate Community Structure In Black Hills Streams, Matthew Lechner
Influence Of Geomorphological Origin Upon Macroinvertebrate Community Structure In Black Hills Streams, Matthew Lechner
Electronic Theses and Dissertations
The purpose of this study was to test a stream classification system proposed for the Black Hills National Forest. Stream physiochemical characteristics and macroinvertebrate community structure were compared among three geomorphically distinct landtype associations in the Black Hills. Stepwise disciminant analysis identified five physiochemical variables, which explained 90% of the variability among landtype associations. The classificatory discriminant procedure correctly reclassified 47 of 52 stations based on the five discriminating invertebrate taxa. Each landtype association was sufficiently different in stream physiochemical characteristics to permit classification. Macroinvertebrates exhibited distributional patterns related to changes in geomorphic structure and stream order, among landtype associations. …
Wildlife Response To Stand Structure Of Green Ash Woodlands, Robert A. Hodorff
Wildlife Response To Stand Structure Of Green Ash Woodlands, Robert A. Hodorff
Electronic Theses and Dissertations
Vegetation, birds and mammals were sampled over two years in two types of green ash woodlands in extreme northwestern South Dakota. Woodlands referred to as closed canopy stands consisted of dense stands of various species of trees and shrubs in different size and age classes. Woodlands referred to as open canopy stands had sparse stands of older trees, with intermediate seedling, sapling and tall shrub layers nearly absent. Closed stands had significantly greater (P = .002) coverage of shrubs in the understory than open stands while open stands had significantly greater (P = .004) total coverage of grasses than closed …
Evaluation Of Seasonal Habitat Use By White-Tailed Deer In Eastern South Dakota, Thomas James Kramlich
Evaluation Of Seasonal Habitat Use By White-Tailed Deer In Eastern South Dakota, Thomas James Kramlich
Electronic Theses and Dissertations
Seasonal use of selected habitat types by white-tailed deer (Odocoileus virginianus) was investigated using radio telemetry locations during 1983 and 1984, on a predominantly agricultural area in east-central South Dakota. In the summer of 1983, radio-collared deer used corn, shelterbelts, and wetlands in proportion to their availability. Soybeans, grainfields, and grasslands were avoided. Deer selected shelterbelts in the fall and wetlands during the winter months, for protective cover. Habitat use shifted in the spring and shelterbelts received heavy use, once they became free of drifted snow. Shelterbelts continued to be selected by deer during the summer of 1984. IN the …
Evaluation Of Structure And Growth Of Bluegills And Black Bullheads Stocked With Largemouth Bass In South Dakota Farm Ponds, Charles E. Morris
Evaluation Of Structure And Growth Of Bluegills And Black Bullheads Stocked With Largemouth Bass In South Dakota Farm Ponds, Charles E. Morris
Electronic Theses and Dissertations
A two-year study estimated standing stock, growth, condition, survival rates, and population structure of bluegills (Lepomis macrochirus) and black bullheads (Ictalurus melas) stocked in South Dakota farm ponds with largemouth bass (Micropterus salmoides). Bluegills and black bullheads reproduced during the second growing seasons and by the end of the study three year-classes of fishes were present in most ponds. Mean back-calculated bluegill total lengths at annuli 1-3 were 58, 125, and 153 mm, respectively. Mean back-calculated black bullhead total lengths at annuli 1-3 were 82, 182, and 240 mm, respectively. A significant north vs south difference (P≤0.05) in third-year bullhead …
Effectiveness Of Shelterbelts In Improving Microclimatic Conditions For Pheasants In Eastern South Dakota, Todd Matthew Schneider
Effectiveness Of Shelterbelts In Improving Microclimatic Conditions For Pheasants In Eastern South Dakota, Todd Matthew Schneider
Electronic Theses and Dissertations
To evaluate wintering habitat for ring-necked pheasants (Phasianus colchicus), this study compared microclimate regimes , as determined by wind and temperature, between shelterbelts containing 1 or 2 rows of coniferous tree species with shelterbelts comprised entirely of deciduous tree species and between wetland and shelterbelt habitats. Maximum temperatures within both shelterbelt types, particularly deciduous shelterbelts, were cooler than outside ambient air temperature during summer. Throughout November, December, and January, minimum temperatures in coniferous shelterbelts types were significantly (P≤0.04) warmer than deciduous shelterbelt types. Effectiveness of shelterbelts in reducing wind velocity decreased from an average of 71% during summer to 28% …
Lungworm Infections, Reproduction And Summer Habitat Use Of Bighorn Sheep In Custer State Park, South Dakota, Gary C. Brundige
Lungworm Infections, Reproduction And Summer Habitat Use Of Bighorn Sheep In Custer State Park, South Dakota, Gary C. Brundige
Electronic Theses and Dissertations
Bighorn sheep (Ovis canadensis) were once indigenous to the Black Hills and Badlands of South Dakota. When European settlers moved into this region during the late 1800' s, market hunting, loss of habitat, and introduction of animal diseases and parasites caused the subspecies of the region, the Audubon's bighorn sheep (O. c. auduboni), to become extinct by 1916 (Buechner 1960). To reestablish bighorn sheep in the Black Hills, 8 Rocky Mountain bighorn sheep (O. c. canadensis) were introduced into the former range of the Audubon's sheep in 1922. Finding the habitat to be very suitable, this small population increased to …
Efficiency Of Two Black-Tailed Prairie Dog Rodenticides And Their Impacts On Non-Target Bird Species, Anthony Dean Apa
Efficiency Of Two Black-Tailed Prairie Dog Rodenticides And Their Impacts On Non-Target Bird Species, Anthony Dean Apa
Electronic Theses and Dissertations
In 1983 zinc phosphide, strychnine with prebait, and strychnine without prebait were applied to black-tailed prairie dog (Cynomys ludovicianus) colonies in west-central South Dakota. Short-term (4 days later) and long-term (1 year later) poison efficiency and impact (short-term and long-term) on horned larks (Eromophila alpestrus) and other seed-eating birds of the prairie dog colonies were evaluated. Prairie dog burrow densities ranged from 54-187 burrows/ha with an average burrow density of 114 ±8 (± SE) burrows/ha. Rodenticide short-term control reduced active burrows by 95% with zinc phosphide, 42% with only strychnine, and 78% with prebaited strychnine. More zinc phosphide was consumed …
Distribution, Temperature Selection, And Gonadal Development Of Fishes In A Power Plant Cooling Reservoir, Henry R. Maddux
Distribution, Temperature Selection, And Gonadal Development Of Fishes In A Power Plant Cooling Reservoir, Henry R. Maddux
Electronic Theses and Dissertations
The distribution, temperature selection, and gonadal development of fishes in the Big Stone Power Plant cooling reservoir were examined from July 1982 through July 1983. A total of 46.8% of the fishes captured during this study were from the discharge area, while 31.8% and 21.4% of the fish occurred in the mixing and intake areas, respectively. The mean water temperature occupied by common carp (Cyprinus carpio) ranged from 7.5 C in February to 31.2 C in August. Black bullheads (Ictalurus melas) were generally benthic and captured in the cooler water. The mean water temperature occupied by black bullheads ranged from …
Abundance, Biomass, And Diversity Of Aquatic Invertebrates In Level Ditches And Adjacent Natural Emergent Marsh In An Eastern South Dakota Wetland, Michael R. Broschart
Abundance, Biomass, And Diversity Of Aquatic Invertebrates In Level Ditches And Adjacent Natural Emergent Marsh In An Eastern South Dakota Wetland, Michael R. Broschart
Electronic Theses and Dissertations
The aquatic invertebrate communities of level ditches and adjacent natural emergent marsh in a South Dakota prairie wetland were sampled during the summer of 1982. Collections were made in both the water column and the bottom substrates. Forty-five taxa were collected. Analysis of variance indicated that a significantly greater mean number of taxa and a larger mean number of all macroinvertebrates were present in level ditches than in the natural emergent marsh. No differences were detected for mean biomass of all macroinvertebrate taxa collectively. Several taxa had a greater mean number and biomass in the level ditches than in the …
Factors Affecting Water Quality And Microinvertebrate Distribution Within A Small Black Hills Stream, Henry G. Drewes
Factors Affecting Water Quality And Microinvertebrate Distribution Within A Small Black Hills Stream, Henry G. Drewes
Electronic Theses and Dissertations
A comparative evaluation of the benthic macroinvertebrate fauna was conducted concurrently with a physiochemical investigation on Slate Creek, Pennington County, South Dakota in the Black Hills. Water quality differences between years and among stations were detected in Slate Creek from both physiochemical and macroinvertebrate evaluations. The primary sources of disturbance to the Slate Creek study site during the sampling period were landscaping activities within the Deerfield Park Resort development and livestock activity. Increased runoff and elevated stream flows in 1982 were responsible for the variation in water quality between years. Water quality differences among stations indicated significantly (P < 0.05) higher turbidity and temperature immediately below the development site in 1981 and 1982. Significantly (P < 0.05) higher fecal coliform bacteria counts were observed at station 5 for both years, resulting from increased livestock activity. Phosphates and nitrates were highest at stations 4 and 5 but were not significantly (P > 0.05) different …
Rainbow Trout Cage Culture And Benthic Production In East-Central South Dakota Dugouts, Glenn David Schuler
Rainbow Trout Cage Culture And Benthic Production In East-Central South Dakota Dugouts, Glenn David Schuler
Electronic Theses and Dissertations
Forty-five cages, encompassing 1.0 m3 of water, distributed between three dugout ponds, were stocked with rainbow trout (Salmo gairdneri) fingerlings to determine the feasibility of raising annual fish crops. Growth rates were compared between feeding rate (0, 3, and 5% body weight/day [bwt/day]) and stocking rate (35, 52, and 70 fish/cage). Growth was significantly (P ≤0.05) greater at feeding rates of 3 and 5% bwt/day than 0% bwt/day. The fish fed 0% bwt/day decreased in mean weight by 0.7 g; the weight gain for the 3 and 5% bwt/day feeding rates were 47.2 and 45.2g, respectively. Significant differences (P ≤ …
Small Mammals In Prairie Wetlands: Habitat Use And The Effects Of Wetland Modifications, Grey W. Pendleton
Small Mammals In Prairie Wetlands: Habitat Use And The Effects Of Wetland Modifications, Grey W. Pendleton
Electronic Theses and Dissertations
Although well documented for other habitat types, small mammal habitat use patterns in prairie wetlands are poorly understood. The distribution of the mammal fauna of South Dakota is also not well known. Because of the lack of information in these areas, evaluation of the impacts of wetland modifications on the resident mammal community is not possible. The objectives of this study were (1) to document the species composition and abundance of small mammal communities inhabiting prairie wetland basins, (2) to determine the effects of small scale habitat modification on small mammals, (3) and to explain local species distribution patterns using …
Brood-Rearing Period Cover Use By Wild Turkey Hens In Southcentral South Dakota, Kevin Francis Mccabe
Brood-Rearing Period Cover Use By Wild Turkey Hens In Southcentral South Dakota, Kevin Francis Mccabe
Electronic Theses and Dissertations
Brood-rearing period cover use by wild turkey (Meleagris gallopavo) hens with broods and those without, in Gregory County, South Dakota, was determined in order to formulate management suggestions for grassland/riparian woodland habitat. Two hens with broods and 12 hens without broods were studies through telemetry and direct observations form 5 July through 2 August and 3 August through 17 August of 1982 and 1982. Vegetational data were collected in 1983. Hens with broods selected for the grass/forb-dominated understory and 52% open canopy of south-facing savannah woodlands while their broods were less than 4 weeks of age. After 4 weeks, broods …
Intensive Culture Of Largemouth Bass And Walleye Fry In Experimental Systems, Gerald A. Wickstrom
Intensive Culture Of Largemouth Bass And Walleye Fry In Experimental Systems, Gerald A. Wickstrom
Electronic Theses and Dissertations
Six genera of invertebrates were made available to largemouth bass (Micropterus salmoides) fry for 25 days. Brachionus spp. was selected for during both day and night (1100 and 2300 h) for the first seven days. Cyclops vemalis was selected on days 1 - 14; it was selected for more during the day for days 1 - 7. Daphnia pulex and D. magna were selected for during days 15 - 25. As the fry grew during the study they ate significantly (P < 0.05) larger D. pulex and D. magna. Moina brachiata was not selected for; it was eaten throughout the study in approximately the same proportion as available. Diaptomus spp. And Ceanestheriella setosa were not eaten. The fry increased in mean length from 6.5 mm on day 1 to 29.8 mm on day 25 of the study. Mean daily length increase was 0.93 mm. Newly hatched walleye (Stizostedion vitreum vitreum) fry were intensively cultured on a diet of live zooplankton under three conditions for 48 days. The fry were reared in tanks under constant illumination (375 lux), in tanks under reduced illumination (105 lux), and in tanks which contained visual interceptors (400 lux). Mean survival of walleyes was 14.0% in tanks under constant illumination, 11.6% in tanks under reduced illumination, and 4.7% in tanks which contained visual interceptors. Mean unaccountable mortality of walleyes was 21.8% in constant illumination tanks, 35.7% in reduced illumination tanks, and 27.4% in tanks with visual interceptors. The fry increased in mean length from 8.6 mm at the start of the study to 36.3 mm (0.76 mm/day) in constant illumination tanks, 36.6 mm (0.76 mm/day) in reduced illumination tanks, and 33.7 mm (0.70 mm/day) in tanks with visual interceptors after 48 days of intensive culture.
Food Selectivity Of Bluegill And Green Sunfish Fry, Aaron Barkoh
Food Selectivity Of Bluegill And Green Sunfish Fry, Aaron Barkoh
Electronic Theses and Dissertations
Four genera of zooplankton and cladoceran egg cases, collected from a municipal sewage lagoon, were made available as food to green sunfish (Lepomis cyanellus) and bluegill (Lepomis macrochirus) fry, to examine their food selectivity. Green sunfish and bluegill fry ranged in size from 8.5-11.0 mm and 8.0-10.5 mm at stocking and were reared for 31 and 30 days, respectively. The gut contents of 1488 green sunfish and 1440 bluegill fry, representing day and night samples were examined. Diet composition was evaluated using the linear food selection index. Both green sunfish and bluegill fry selected for Cvclops vernalis and consistently selected …
An Economic Valuation Of South Dakota Wetlands As A Recreation Resource For Resident Hunters, Craig W. Johnson
An Economic Valuation Of South Dakota Wetlands As A Recreation Resource For Resident Hunters, Craig W. Johnson
Electronic Theses and Dissertations
In spite of efforts to conserve wetlands, intensified agriculture, water projects, and urban development annually diminish the quantity and quality of wetland resources (Weller 1981). Leitch and Danielson (1979) noted that when the discounted value of the returns to drainage exceed drainage costs there is an economic incentive to drain. If present drainage rates continue, Weller (1981) estimated that most wetlands will disappear by the year 2140. Research has only recently focused attention on the need to estimate the public value of wetland benefits and the social costs of drainage (Leitch and Danielson 1979). The disparity between private and social …
Angler Harvest Survey Of Lake Francis Case, South Dakota, Lawrence M. Miller
Angler Harvest Survey Of Lake Francis Case, South Dakota, Lawrence M. Miller
Electronic Theses and Dissertations
An angler harvest survey, consisting of two independent surveys, was conducted on Lake Francis Case, South Dakota, from May through October 1981, and April through October 1982. An aerial angler count was used to estimate angle pressure, and an angler interview survey was used to estimate catch rate. In 1981, a section of Lake Francis Case in the vicinity of the Gregory County Pump Storage Project (Zone 2) was surveyed. IN 1982, the survey was expanded to include the entire reservoir (additional Zones 1 and 3). Estimated fishing pressure for Zone 2 in 1981 was 188,631 angler-hours and in 1982 …
Use Of Eastern South Dakota Shelterbelts By Nesting Birds Of Prey, Scott E. Norelius
Use Of Eastern South Dakota Shelterbelts By Nesting Birds Of Prey, Scott E. Norelius
Electronic Theses and Dissertations
This study was conducted in 1979 and 1980 to determine abundance, productivity, food habits, and ranges of raptors utilizing shelterbelts were in a 78 km² Brookings County study area. The shelterbelts were heterogeneous stands of trees and shrubsplanted in linear rows. Major tree species included elm (Ulmus spp.), green ash (Fraxinus pennsylvanica), cottonwood (Populus deltoids), Russian olive (Elaeagnus angustifolia), and eastern red cedar (Juniperus scopulorum). Major shrub species included honeysuckle (Lonicera tatarica) and lilac (Syringa vulgaris). Ninety-eight raptors were observed on the study area over the 2 breeding seasons investigated (1979-1980). Species observed were the American kestrel (Falco sparverius), Swainson’s …
Birds On Modified Wetlands In Eastern South Dakota, E. Nell Brady
Birds On Modified Wetlands In Eastern South Dakota, E. Nell Brady
Electronic Theses and Dissertations
To examine the role of bird species (other than Anatidae) in the prairie wetlands ecosystem. Seven wetlands on Waterfowl Production Areas in eastern South Dakota were utilized to measure differences between bird communities in plots with dug brood complexes and non-modified plots. Thirty-eight species of wetland birds were recorded on wetlands during June 1981 and June 1982. The most abundant species included the red-winged blackbird (Agelaius phoeniceus), marsh wren (Cistothorus palustris), and song sparrow (Melospiza melodia). Analysis of variance was used to test between treatment (modified and natural plots on the wetlands) differences for the dependent variables: density, bird species …
Dispersal And Harvest Of Sage Grouse Utilizing The Test Reactor Area Of The Idaho National Engineering Laboratory, Howard W. Browers, Jr.
Dispersal And Harvest Of Sage Grouse Utilizing The Test Reactor Area Of The Idaho National Engineering Laboratory, Howard W. Browers, Jr.
Electronic Theses and Dissertations
A radio telemetry study of sage grouse (Centrocercus urophasianus) summering at the Test Reactor Area (TRA) on the Idaho National Engineering Laboratory (INEL) in southeastern Idaho was initiated in July 1980. Objectives included determination of habitat use, home range, brood breakup, fall movements, and harvest of sage grouse using the TRA. Supplemental habitat data and fall movement data were collected from sage grouse summering at the Central Facilities Area (CFA) on the INEL in 1982. Seasonal precipitation appeared to influence the period of use of the TRA by sage grouse. Grouse arrived later and left earlier in the wet year …
Recreational Use Of Six Prairie Wetlands In Eastern South Dakota, Timothy Allen Thompson
Recreational Use Of Six Prairie Wetlands In Eastern South Dakota, Timothy Allen Thompson
Electronic Theses and Dissertations
A recreational use survey was conducted at 6 public wetlands in eastern South Dakota from August 9, 1981 through August 8, 1982. Four hundred and fifty-eight postcard questionnaires were placed on vehicles encountered at these marshes during random time periods. Two hundred and thirty-five were voluntarily returned for a response rate of 51.3%. Approximately 10, 020 people made 4,778 trips to these wetlands and spent 63, 093 man-hours. Thirty-one different activities were observed or reported. Hunting accounted for 96.0% of all fall trips and 89.1% of yearly visits. Over 89% of all visits occurred during fall and over 50% of …
Feeding Behavior, Food Consumption, Growth, And Survival Of Hybrid Grass Carp (Hypophthalmichthys Nobilis X Ctenopharyngodon Idella) In South Dakota, Marc C. Harberg
Feeding Behavior, Food Consumption, Growth, And Survival Of Hybrid Grass Carp (Hypophthalmichthys Nobilis X Ctenopharyngodon Idella) In South Dakota, Marc C. Harberg
Electronic Theses and Dissertations
Plant preference of yearling hybrids (Hypophthlmichthys nobilis X Ctenopharyngodon idella) was examined under control conditions at the Gavins Point National Fish Hatchery, Yankton, South Dakota and under field conditions in two stockwater impoundments in south-central South Dakota. IN feeding trials, conducted in a 0.07 ha hatchery pond, hybrid grass carp selected Najas guadalupensis, Chara sp. and Potamogeton pectinuatus. Ceratophyllum demersum and Myriophyllum spicatum were not consumed. Under field conditions N. guadalupensis also appeared to be preferred while C. demersum was not. Feeding behavior, daily consumption, growth, and survival were also evaluated in the two stockwater impoundments. Hybrids averaging 51g were …
Rainbow Trout (Salmo Gairdneri) Cage Culture And Primary Production In Eastern South Dakota Dugout Ponds, Michael John Roell
Rainbow Trout (Salmo Gairdneri) Cage Culture And Primary Production In Eastern South Dakota Dugout Ponds, Michael John Roell
Electronic Theses and Dissertations
Rainbow trout (Salmo gairdneri) reared in 1 m³ cages in a South Dakota dugout pond grew and survived as well or better than most cage-cultured rainbow trout reported in the literature. Significant differences (P≤0.01) in mean length, weight, and food conversion, and similarity in relative weight between trout fed 2 and 4% of body weight daily, indicated that the optimum feeding rate was near 3% for this size range (35=100g). Daily rations based on fish size and water temperature need to be developed for trout reared in a lentic environment. The high cost of fingerlings was the limiting factor in …
Waterfowl Pair And Brood Use Of Dug Brood Complexes In East-Central South Dakota, Beth A. Giron Pendleton
Waterfowl Pair And Brood Use Of Dug Brood Complexes In East-Central South Dakota, Beth A. Giron Pendleton
Electronic Theses and Dissertations
Modification of wetlands has been a frequently employed management technique to enhance habitat for waterfowl and other wetland wildlife. One type of excavation in wetland basins is the dug brood complex; an interconnected system of pond units, channels, and islands, primarily created to provide waterfowl brood rearing habitat during drought. In 1981-82, a study was conducted to evaluate waterfowl pair and brood use of 8 pairs of Class IV wetlands in east-central South Dakota. Each pair consisted of a wetland with a dug brood complex (modified) and an unmodified basin of comparable basin size. Under drought conditions in 1981, both …
The Phosphacylium Ion: Evidence For Its Existence As An Intermediate In Reactions Of Organophosphates, Thomas D. Matus
The Phosphacylium Ion: Evidence For Its Existence As An Intermediate In Reactions Of Organophosphates, Thomas D. Matus
Electronic Theses and Dissertations
Prior to this work, no strong evidence existed which unequivocably proved the existence of phosphacylium ions as intermediates in reactions of this type. It is the object of this study to look into nucleophilic substitution at phosphorus, and the intermediates of these possible dissociative type reactions.