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Full-Text Articles in Physical Sciences and Mathematics

Development Of Techniques For Distribution Of Baits To Raccoon For Chemosterilant Studies, Richard L. Nelson Jan 1972

Development Of Techniques For Distribution Of Baits To Raccoon For Chemosterilant Studies, Richard L. Nelson

Electronic Theses and Dissertations

Sudan Red IV, Sudan Black B, and demethylchlortetracycline (DMCT) were tested as physiological markers in baits for raccoon (Procyon lotor). DMCT was readily detected in the jawbone of raccoons given 50 mg when examined under an ultraviolet light at period of 7, 30, 75, and 450 days following treatment. Seven days after administering 75 mg of Sudan Red IV, it could not be detected in fat deposits. Sudan Black B, administered in similar dosage, could not be detected at 30 days. A total of 1826 chicken eggs containing 50 mg DMCT was distributed on a 25 square-mile study area between …

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Effects Of Diethylstilbestrol On Reproduction In The Black-Tailed Prairie Dog, Donald G. Pfeiffer Jan 1972

Effects Of Diethylstilbestrol On Reproduction In The Black-Tailed Prairie Dog, Donald G. Pfeiffer

Electronic Theses and Dissertations

Research was conducted in southwestern South Dakota in 1970 and 1971 to obtain information on the reproductive cycle of the black-tailed prairie dog (Cynomys ludovicianus) and to test effectiveness of diethylstilbestrol as a reproductive inhibitor. Embryo body lengths from 10 pregnant females were compared to body lengths of 14 known day-old young to learn the peak breeding period when an estrogenic chemosterilant would be most effective. Conception dates were obtained for three females by backdating the gestation period. The breeding peak was found to occur in late February and early March in South Dakota. Nine of 11 Prairie dogs were …

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Food Selectivity Of The Black Bullhead (Ictalurus Melas, Rafinesque) In Lake Poinsett, South Dakota, Andrew J. Repsys Jan 1972

Food Selectivity Of The Black Bullhead (Ictalurus Melas, Rafinesque) In Lake Poinsett, South Dakota, Andrew J. Repsys

Electronic Theses and Dissertations

The food habits of young-of-the-year, subadult and adult black bullheads were studied in Lake Poinsett, South Dakota, from March, 1970, to April, 1971. Two hundred twenty young-of-the-year (37-87 mm total length) fed primarily on limnetic cladocerans and copepods. Leptodora and Diaphanosoma comprised 86.5% of the total food volume. Chironomid larvae and pupae made up 5.6% of the total. Other benthic organisms and littoral cladocerans together contributed less than 1%. Stomach contents of 608 subadult and adult black bullhead (143-304 mm total length) indicated significant seasonal vairaiton in diet. Daphnia pulex and chronomid larvae were important food items in winter. Bullheads …

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Food Habits Of Fish In A Multispecies Farm Pond, Thomas W. Gengerke Jan 1972

Food Habits Of Fish In A Multispecies Farm Pond, Thomas W. Gengerke

Electronic Theses and Dissertations

Food habits of yellow perch, bluegill, and black crappie were studied during 1970 and 1971 in Abbey Pond, South Dakota. Aquatic insects, zooplankton, mollusks, and fish were the most frequently consumed food items by the three species. Yellow perch led primarily on aquatic insects, zooplankton, and mollusks. Aquatic insects were dominant (by volume) in 40.0 and 61.5 percent of the samples respectively for the two years. Zooplankton, mollusks, aquatic insects, and bryozoans were the dominant food items by volume of adult bluegills. On an annual basis aquatic insects were the most important food item in the diet. Adult black crappies …

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Waterfowl Production In The James River Valley Of South Dakota, William E. Wheeler Jan 1972

Waterfowl Production In The James River Valley Of South Dakota, William E. Wheeler

Electronic Theses and Dissertations

A study of waterfowl production was conducted on two study areas in the James River Valley of South Dakota in 1971 and 1972. Its objectives were to measure rates of reproductive success and to determine the effect of land use and other influences on duck production. The five most abundant species of nesting ducks were blue-winged teal (Anas discors), mallard (platyrhvnchos), gadwall (A. strepera), shoveler (clypeata), and pintail (acuta). Seventy-two percent of the wetland habitat on the study areas consisted of temporary (Type l and Type 3) water areas. Only 3.9 percent of the wetlands represented semi-permanent (Type 4) and …

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Effects Of Polychlorinated Biphhenyls In The Ring-Necked Pheasant, Robert Bernard Dahlgren Jan 1972

Effects Of Polychlorinated Biphhenyls In The Ring-Necked Pheasant, Robert Bernard Dahlgren

Electronic Theses and Dissertations

In 1970 and 1971, cock pheasants (Phasianus colchicus) were given single capsules weekly containing 0 and 25 mg polychlorinated biphenyls (PCB), Aroclor 1254, and hens were given O, 12.5, and 50 mg. Egg production was reduced (P<0.01) in the hens given 50 mg PCB both years. Fertility, determined by visual inspection of incubated eggs, was unaffected by PCB. Hatchability was lowest in the group of hens given 50 mg in both years but significantly lower (P<0.01) only in 1971. PCB adversely affected the viability of the embryo both years, as the number of eggs pipped but not hatched in PCB groups was higher (P<0.05). PCB did not affect eggshell thickness. Behavior on the visual cliff shortly after hatching was affected among offspring of hens given 50 mg PCB in 1970 (P,0.01). Offspring of hens given 50 mg chose the visually-deep side of the cliff. No differences in behavior on the visual cliff were evident in 1971. Response to hand catching of offspring was affected in 1970 (P <0.01). The ability of penned pheasants to avoid hand capture was least where both parents received PCB, followed by those where hens only, cocks only and neither parent received PCB. No differences in response to hand capture among groups were found in 1971. Weights of chicks from hens on 50 mg were lower (P<0.01) at 6 weeks of age in 1970. This effect was not seen in 1971. Survival of chicks in brooders to 6 weeks of age was lower (P<0.01) in offspring of hens given 50 mg PCB weekly in 1970. No differences were found among offspring of treatment groups in 1971. Survival from 6 weeks of age to fall was similar in all groups. Overall survival from hatching to fall was less (P<.0.05) in offspring of hens given 50 mg weekly in both years combined. No differential effect was found between sexes for survival. PCB in doses varying front 10 mg to 210 mg daily caused hyper-excitability, weakness, tremoring, lack of appetite, lack of feathers, and a comatose death. Birds 11-weeks old given 10 or 20 mg PCB daily, birds 6 to 9 months old given 50 or 100 mg each 3.5 days, and adult hens given up to 50 mg once a week continued to eat. Eleven-week old birds given 210 mg daily stopped eating or those given 210 mg daily, the heaviest birds lost the greatest percentage of their weight (15 to 31 percent) before death occurred (1.3 to 4.3 days). Birds intentionally starved at the same time lost a greater percentage of weight (27 to 51 percent) before death (2.3 to 8.6 days). Some adult hens were given a single 50-mg capsule and samples of whole body, brain, liver, muscle, eggs, and feces were analyzed to determine patterns of storage and excretion. Levels of PCB were highest at 12 hours after capsule administration. Residues were highest in liver, followed by brain and muscle over 28 days following the single 50-mg capsule. From 94 to 98 percent of the administered dose was absorbed and 40.5 mg of the 50mg were in the body after 28 days. Hens were in a state of low egg production and excreted 4.2 mg in the eggs and 4.0 mg in the feces over 28 days. Excretion in the egg could be an important means of ridding the body of PCB. Four hens from the 1970 breeding experiment, given 17 capsules weekly containing 12.5 mg PCB and killed 1 week following the last capsule, had from 37 to 56 percent of the administered dose in their bodies. Four hens on the 50-mg level in 1970 had from 60 to 82 percent of the dose given. Five hens given 12.5 mg weekly for 16 weeks in 1971 had an average of 23.8 ppm PCB in their bodies 1 week after the last capsule, three hens had an average of 13.6 ppm after 3months on a clean diet, and three others had an average of 20.9 ppm after 6 months. Excretion was variable and slow. An analysis of brain, liver, and muscle tissues from dead and surviving birds fed PCB at various levels showed that brain residue levels from 300 to 400 ppm wet weight were indicative of death from FCB toxicosis. Liver and muscle levels were too variable to be useful in assessing cause of death. Administration of PCB decreased weights of heart and spleen (P <0. 01) at all levels given and increased weights of kidneys and livers in birds given 10- and 20-rng doses daily (P <0. 01) but not in birds given 210 mg daily. Splenic atrophy, where spleens were small, pale-tan color, and had wrinkled capsules resulting from depletion of lymphatic nodules, was characteristic of birds given PCB. PCB and dieldrin were given singly and jointly, and only additive, not synergistic, effects were noted. Livers of wild pheasants from Pennsylvania, Indiana, and South Dakota had no more than 2 ppm PCB. This indicates low-level contamination.

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Use Of Waterfowl Production Areas By Ducks And Coots In Eastern South Dakota, Spencer Vaa Jan 1972

Use Of Waterfowl Production Areas By Ducks And Coots In Eastern South Dakota, Spencer Vaa

Electronic Theses and Dissertations

The use of Waterfowl Production Areas (WPA) by American coots (Fulica americana) and ducks was studied during 1970 and 1971 in east-central South Dakota The Eriksrud WPA, a type IV wetland with 55 acres of water area and 35 acres of upland, contained 188 coot nests during the 2-year study. Of the 188 coot nests, 178 hatched for a success rate of 95 percent. Average clutch size of 130 completed clutches was 8.4. Average size of 21 coot broods from 4 to 6 weeks of age was 6.1. Coot production on the Eriksrud area was estimated at 543 young per …

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Use Of Eelctrophoresis To Determine Populations Of Pheasants In South Dakota, David George Montag Jan 1972

Use Of Eelctrophoresis To Determine Populations Of Pheasants In South Dakota, David George Montag

Electronic Theses and Dissertations

The ring-necked pheasant (Phasianus colchicus) is an important game bird, and various management techniques have been implemented in its behalf. One of the most common practices has been transplanting or stocking wherein pheasants are introduced into an area with a depleted population in hopes of increasing pheasant production. The effects of such programs are difficult to evaluate since there is no way of knowing if the introduced birds are in any way responsible for production changes which subsequently occur. If the taxonomic characteristics of the native and the introduced populations could be determined, the effect that introduced birds have on …

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Movements And Habitat Use By Hen Pheasants During Brood Rearing, Lynn E. Hanson Jan 1971

Movements And Habitat Use By Hen Pheasants During Brood Rearing, Lynn E. Hanson

Electronic Theses and Dissertations

Land-use patterns characteristic of prime pheasant range in the Great Plains and prairie region have 50-75 percent of the land under cultivation according to Kimball et. al. (1956). Farmland is pheasant habitat, and the production of pheasants is therefore greatly influenced by farming practices. Considerable research has been done on rates of pheasant production, nest success, and cover preferences for nesting. However, little information has been obtained on movements and cover preferences for brood rearing. Most studies of the type of cover utilized by pheasant broods have been based on roadside and random field observations. Kozicky and Hendrickson (1951) carried …

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Interpretive Potential Of South Dakota Wetlands, Douglas C. Harr Jan 1971

Interpretive Potential Of South Dakota Wetlands, Douglas C. Harr

Electronic Theses and Dissertations

A study was initiated to devise a method for selecting prairie wetlands on which nature interpretation areas could be established. An evaluation form was designed to systematically identify areas of good potential and 64 prairie wetlands were evaluated. Twenty-two percent of the evaluated marshes were found to rank “excellent”: the method of evaluation was determined successful. A survey was initiated to determine visitor preferences for interpretive methods and facilities at an existing wildlife-interpretive trail. Seventy-nine percent of the visitors indicated preference for a self-guiding interpretive trail. Maps and pictures used in conjunction with self-guiding signs were deemed important. Ninety-one percent …

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Effects Of Chick Stimuli And Dieldrin On Adoptive Behavior Of Penned Hen Pheasants, K. L. Cool Jan 1971

Effects Of Chick Stimuli And Dieldrin On Adoptive Behavior Of Penned Hen Pheasants, K. L. Cool

Electronic Theses and Dissertations

Studies to determine the effect of chick stimuli and dieldrin on adoptive behavior of penned hen pheasants were conducted in 1969 and 1970. Results indicated that whether caged hens saw or heard chicks had no effect on adoption or killing of chicks. Hens receiving sound stimuli and sight-and-sound stimuli from chicks responded similarly to hens receiving no stimuli. Sub-lethal doses of dieldrin also had no effect on chick adoption under the conditions of this study. Results demonstrated that non-incubating pheasant hens will adopt and brood orphan chicks. During the 2 years of the study, respectively, 37 and 49 percent of …

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Food Habits Of Black Crappies, White Crappies, Yellow Perch And White Suckers In A Small Impoundment In Northeastern South Dakota, Dennis Unkenholz Jan 1971

Food Habits Of Black Crappies, White Crappies, Yellow Perch And White Suckers In A Small Impoundment In Northeastern South Dakota, Dennis Unkenholz

Electronic Theses and Dissertations

Crustaceans, aquatic insects and fish were the most important food items found in stomach samples. Black crappies depended on zooplankton and aquatic insects as their major food source as they occurred in all samples and were major food items in 70 percent and 40 percent respectively. Insects, zooplankton and fish were the major food items of white crappies. Insects were the dominant forage present in 54 percent of the samples while zooplankton and fish were dominant in 36 percent and 21 percent of the samples respectively. Perch relied on crayfish, fish and aquatic insects as their major food source. Aquatic …

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Population Dynamics Of The Mourning Dove In South Dakota, Leslie A. Rice Jan 1971

Population Dynamics Of The Mourning Dove In South Dakota, Leslie A. Rice

Electronic Theses and Dissertations

Mourning dove bandings in South Dakota totaled 44,842 from 1917 through 1970. Adult bandings totaled 44.4 percent of all bandings while immatures, juveniles, locals, and unknown age were 41.3, 0.8, 12.8, and 0.7 percent, respectively. Recoveries totaled 2.8 percent of the banded population, 2.5 percent from hunting and 0.5 percent from non-hunting. Annual mortality estimates of local (nestling) bandings from 1956-61 were between 54.4 and 64.5 percent. Subsequent adult mortality from local bandings was between 51.0 and 52.4 percent. Mean annuals mortality estimates of flying doves banded from 1964-69 were calculated using composite dynamic, composite time-specific, relative recovery rate, a …

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Food Habits Of Deer In The Southern Black Hills As Determined By The Point Technique, Theron E. Schenck Jan 1971

Food Habits Of Deer In The Southern Black Hills As Determined By The Point Technique, Theron E. Schenck

Electronic Theses and Dissertations

White-tailed (Odocoileus virginianus) and mule deer (Odocoileus hemionius) were collected in 1968 and 1969 for a study of food habits. Rumen contents were analyzed by use of the point-analysis technique and weights. This is the first food habits study from the southern Black Hills and is necessary for proper deer management. To evaluate the suitability of the point technique for Black Hills vegetation, an artificial population was constructed from known weights of a forb, (Achillea lanulosa), grass (Oryzopsis asperfoliz), rose (Rosa sp.), kinnikinnick (Arctostaphylos uva-ursi), and ponderosa pine (Pinus ponderosa). Each population was tested with 100-point trails and 200-point trials. …

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A Clinico-Pathologic Study Of Botulism In Ring-Necked Pheasants, Hazel J. Shave Jan 1971

A Clinico-Pathologic Study Of Botulism In Ring-Necked Pheasants, Hazel J. Shave

Electronic Theses and Dissertations

Toxins were produced from 6 strains of Cl. Botulinum, 2 of which killed pheasants. Inoculated birds were observed and a description of the progression of signs of the disease is given. Juvenile pheasants were inoculated with Types A and C toxin intramuscularly and were given the toxin orally. These birds were observed and their clinical signs noted. Adult pheasants were inoculated with toxoid prepared from type C toxin and commercial toxoid; injections were repeated in 21 days. Fourteen days following the final injection, the birds were challenged with toxin. Those protected with toxoid survived, while those receiving saline succumbed. Gross …

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Macroscopic Benthos Populations And Taxonomy Of The Family Chironomidae In Lake Poinsett, South Dakota, Stephen B. Smith Jan 1971

Macroscopic Benthos Populations And Taxonomy Of The Family Chironomidae In Lake Poinsett, South Dakota, Stephen B. Smith

Electronic Theses and Dissertations

Benthos samples were collected in Lake Poinsett, a highly eutrophic eastern South Dakota lake, from March 1970 through February 1971. The lake bottom was divided into three substrate types (sand, sand-sapropel mixture and sapropel) and the percent of each substrate type was calculated. Nineteen macroscopic genera were taken from ten sampling stations located throughout the lake. Descriptions are presented for organisms in this group. Diversity of organisms was greatest in the sand substrates, in that all 19 genera were collected. Chironomus spp. (Chironomus plomosus, Chironomus attenuates and six unidentified species) was the most abundant group of organisms and occurred most …

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The Chemistry Of Some Unusual Carbodiimides, Donald Melvin Plautz Jan 1971

The Chemistry Of Some Unusual Carbodiimides, Donald Melvin Plautz

Electronic Theses and Dissertations

Several N1-alkyl-N2-(N,N-dialkylamino)carbodiimides, which were found to form dimeric species, were prepared, and the structure of the dimeric species determined. A study of the reaction chemistry of both the monomeric and dimeric carbodiimides led to the conclusion that dimerization occurred via a (π2s + π2a) ground-state, symmetry-allowed mechanism, and that thermal decomposition of the dimeric species occurred via a (π2s +-π2s) excited-state, symmetry-allowed mechanism. Although dialkylphosphoramidates have been shown to be useful intermediates in the preparation of unsaturated organic nitrogen compounds, N-acyl- and N-imino-dialkylphosphorohydrazidates were found to be too unstable, forming trialkylphosphates upon distillation, to be of …

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Nutrient Transport In The Lake Poinsett System, Jack M. Skille Jan 1971

Nutrient Transport In The Lake Poinsett System, Jack M. Skille

Electronic Theses and Dissertations

Concentrations and loads of nutrients transported through the Lake Poinsett system were monitored from April 1, 1970 to April 1, 1971. An annual 2.07x 10~ m3 surface discharge into Lake Poinsett transported 1.66 x 104 kg (PO4) phosphorus, 1.28 x 104 kg nitrate nitrogen, and 3.90 x 104 kg organic carbon. The Big Sioux River-Dry Lake system contributed 63% of the phosphorus, 45% of the nitrate nitrogen, and 43% of the organic carbon load. The remaining portion entered Lake Poinsett from the Lake Albert drainage. Of the annual load of nutrients transported into Lake Poinsett, 33% of the nitrate nitrogen …

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Seasonal Movements And Behavior Of Ring-Necked Pheasants In Eastern South Dakota, Arthur V. Carter Jan 1971

Seasonal Movements And Behavior Of Ring-Necked Pheasants In Eastern South Dakota, Arthur V. Carter

Electronic Theses and Dissertations

Information was gathered on mobility, behavior, and related activities of pheasants from July 1966 to July 1968 by banding and/or marking 160 birds with backtags and radio transmitters. Food was readily available since the winters were mild with little snow. Birds moved less than 1/4 mile from roosting areas to cornfields and weed patches to feed. Numbers of birds dispersing from the study area in spring varied each of the years, but 60 to 70 remained there during the two reproductive seasons. Adult cocks traveled less than 1/4 mile when dispersing-and adult hens moved less than 1/2 mile. Movements by …

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Effects Of Dieldrin On The Social Interactions Of Penned Pheasants And Chickens, Nancy Hayden Field Jan 1971

Effects Of Dieldrin On The Social Interactions Of Penned Pheasants And Chickens, Nancy Hayden Field

Electronic Theses and Dissertations

Studies to determine the effects of dieldrin on social hierarchy of pheasants and chickens were initiated in 1970. Social interactions were observed among groups of pheasant chicks, adult cock and hen pheasants and peck-order development among groups of young pheasants. To determine the effects of dieldrin on the pecking behavior of individual birds, pairs of pheasants and pairs of chickens were placed in a neutral cage. When patterns of dominance and subordination were consistent, dieldrin in capsules (4 mg to pheasants and 6 and 10 mg to chickens twice weekly) was given to one member of each pair and birds …

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Phytoplankton Dynamics Of Two Northern Prairie Lakes And Possible Relations To Dissolved Nutrients, Alan B. Hauber Jan 1971

Phytoplankton Dynamics Of Two Northern Prairie Lakes And Possible Relations To Dissolved Nutrients, Alan B. Hauber

Electronic Theses and Dissertations

Phytoplankton populations in Enemy Swim Lake were observed to be quite different. Although these lakes lie within the same geographic area (Coteau des Prairies), major differences in water quality were recorded. The differences in water quality were reflected in the phytoplankton populations and appeared to be influenced by the agricultural practices on the watersheds. Enemy Swim Lake was basically a diatom lake while Lake Herman contained mostly blue-green algae. Genera of algae found in Enemy Swim Lake were: Anabaena, Aphanizomenon, Lyngbya, Pediastrum, Staurastrum, Dinobyron, Asterionella, Fragilaria, Melosira, Stephanodiscus, and Ceratium. All of the above genera occurred in Lake Herman except …

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A Comparison Of Aspen And Pine Communities In The Northern Black Hills, Jeremiah J. Kranz Jan 1971

A Comparison Of Aspen And Pine Communities In The Northern Black Hills, Jeremiah J. Kranz

Electronic Theses and Dissertations

Three study areas, each containing an aspen (Populus tremuloides) community, a pine (Pinus ponderosa) community, and a mixed aspen-pine community, were studied during the summers of 1968, 1969, and 1970. Soil chemistry, plant chemistry, overstory density, understory production, and use by whitetail deer (Odocoileus virginianus) and cattle (Bos taurus) were determined for each community in each study. Pine and aspen communities of one study area were sampled for soil and plant chemistry. Soil phosphate and potassium levels were higher in the aspen community, while soil nitrates were higher in the pine community. Soil pH was similar to the two communities. …

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Effects Of Aldrin On Young Pen-Reared Pheasants, Joseph Edward Hall Jan 1970

Effects Of Aldrin On Young Pen-Reared Pheasants, Joseph Edward Hall

Electronic Theses and Dissertations

Three levels of encapsulated aldrin (.05, 1.0, and 1.5 mg) were administered weekly to young pen-reared pheasants from 5 to 11 weeks of age to determine effects on growth and residue levels in brain, feathers, and whole body during and after treatment. During treatment, birds were weighed weekly. After treatment ceased, birds were weighed every other week until 21 weeks of ---. Analysis of residues was by electron capture gas chromatography. Growth of pheasants --- 5 to 21 weeks of age was depressed (P 0.01) by administration of aldrin dosages of 1.0 to 1.5 mg. Aldrin values in the brain …

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Ecology Of The Black-Footed Ferret And The Black-Tailed Prairie Dog, Robert G. Sheets Jan 1970

Ecology Of The Black-Footed Ferret And The Black-Tailed Prairie Dog, Robert G. Sheets

Electronic Theses and Dissertations

Research involving the black-footed ferret (Mustela nigripes) and black-tailed prairie dog (Cynomys ludovicianus) was conducted during 1968 and 1969. Eighteen prairie dog burrows were excavated in 1968 and 1969. Burrow systems ranged from 13 to 109 feet long and 3 to 14 feet deep. Fifteen of the burrows exhibited dome-shaped entrances leading to a gradually descending passageway which made an abrupt vertical ascent to a crater-shaped entrance. Nest chambers were found in 6 burrows. Earthen plugs created by prairie dogs in burrows after ferret departure ranged from 9 to 33 feet long. Eighty-two ferret scats were recovered. Animal remains found …

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Pheasant Use And Waterfowl Production On State And Private Lands, Charles R. Elliott Jan 1970

Pheasant Use And Waterfowl Production On State And Private Lands, Charles R. Elliott

Electronic Theses and Dissertations

Ring-necked pheasant (Phasianus colchicus) use on state-owned game production areas was compared to that on privately-owned areas in east-central South Dakota. Four 80-acre and four 160-acre tracts of state lands were paired with private areas of the same size having the same amount of wetland and were selected from aerial photographs taken before the purchase of the state-owned areas. None of four nests were successful on private areas in 1968 and three of five nests were successful on game production areas. In 1969 three of 19 nests were successful on private areas and 10 of 21 nests were successful on …

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Feeding Of Black Bullheads Ictalurus Melas (Rafinesque) In Experimental Cages, Kay R. Hill Jan 1970

Feeding Of Black Bullheads Ictalurus Melas (Rafinesque) In Experimental Cages, Kay R. Hill

Electronic Theses and Dissertations

Black bullheads, Ictalurus melas (Rafinesque), were grown experimentally from July 25, 1969, through October 21, 1969. The fish, collected from Lake Poinsett, were grown in five cages each with a water volume of 2.6 m³ and five cages each with a volume of 3.86 m³. The larger cages contained nearly 60 percent of the total 323 m³ of water volume in the cages. No significant difference in fish growth between the two cage sizes were observed. Fish in large cages gained 204.4 Kg and were fed 1550.8 Kg of food, for a food conversion of 6.60. Fish in smaller cages …

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An Evaluation Of The Roadside Technique For Censusing Breeding Waterfowl, Darrel W. Sauder Jan 1969

An Evaluation Of The Roadside Technique For Censusing Breeding Waterfowl, Darrel W. Sauder

Electronic Theses and Dissertations

An evaluation of the roadside technique for censusing breeding waterfowl was conducted in east-central South Dakota. On the 54-mile transect used in 1968, number of coutns necessary to be within 20 percent of population mean with specified confidence of 0.90 for blue-winged teal (Anas discors) and gadwall (Anas strepera) was five and three using miles or wetlands. Within same limits counts needed for mallard (Anas platyrhynchos) were at least four for miles and three for wetlands. Shorter transects, used in 1967 required more counts. Transects 21 miles long required up to 10 counts based on miles and 11 based on …

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Food Selectivity Of Bigmouth Buffalo (Ictiobus Cyprinellus, Valenciennes) In Lake Poinsett, South Dakota, Victor J. Starostka Jan 1969

Food Selectivity Of Bigmouth Buffalo (Ictiobus Cyprinellus, Valenciennes) In Lake Poinsett, South Dakota, Victor J. Starostka

Electronic Theses and Dissertations

Food habits of bigmouth buffalo fry, subadults, and adults were studied in lake Poinsett, South Dakota, from January to November, 1968. Fifty-six fry fed primarily (75.0% by volume) on benthic organisms. Four hundred fifty-five subadults and adults fed entirely on plankton. Daphnia pulex adults comprised 83.7 to 96.7% of the food items during periods of ice cover (January to April). Daphnia pulex adults and juveniles comprised 68.5% by volume and cyclopoid copepods 29.7%^ of the diet from April to July. Summer (July to October) samples showed ingestion of D. pulex adults and juveniles (36.9%), Anacystis sp. (22.3%), and Daphnia galeata …

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Water Quality Changes Under Ice Cover In Northern Prairie Lakes, Steven P. Gloss Jan 1969

Water Quality Changes Under Ice Cover In Northern Prairie Lakes, Steven P. Gloss

Electronic Theses and Dissertations

Water quality changes under ice cover were studied in seven northern prairie lakes. The lakes are high in dissolved materials and exist essentially as closed systems during the winter months. Ice cover ranging from 53 to 86 cm developed on the lakes. Melted ice samples showed small amounts of dissolved impurities present in surface layers of the ice. No substantial concentrations of any ions were found in the ice of lower layers. Specific conductance increased over 40% under ice cover in two of the lakes studied. Increases in other lakes ranged from 19 to 38%. Major ions showed increases similar …

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Evaluation Of The Ovulated Follicle Technique As A Means Of Determining Pheasant Production, C. Denis Allen Jan 1969

Evaluation Of The Ovulated Follicle Technique As A Means Of Determining Pheasant Production, C. Denis Allen

Electronic Theses and Dissertations

A study of the ovulated follicle technique for determining egg production in pheasants was conducted during 1967 - 1969. Evidence indicated collection of wild hens for follicle counts should be between 5 and 14 weeks after cessation of laying. Questionable follicles encountered should be considered ovulated follicles and included in the counts. Most questionable follicles were believed to originate from ovulated atretic follicles that were harder to identify because of their particular stage of regression. The influence of freezing on atretic follicle counts was studied, and no adverse effects were found. A technique was developed for selectively staining atretic follicles. …

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