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Litter Production And Nutrient Content Of Litter In The Seasonally Flooded Dismal Swamp, Marta M. Gomez Oct 1980

Litter Production And Nutrient Content Of Litter In The Seasonally Flooded Dismal Swamp, Marta M. Gomez

Biological Sciences Theses & Dissertations

Litter production was studied in four plant communities in the Great Dismal Swamp, Virginia, that differ primarily in species composition and flooding regime. Greatest leaf deposition occurred in the more flooded communities, maple-gum (Acer-Nyssa) with 536 g m-2 yr-1 and cypress (Taxodium distichum (L.) Richard) with 528 g m-2 yr-1, followed by the cedar (Chamaecyparis thyoides (L.) BSP) and mixed hardwood (Quercus-Acer-Nyssa-Liquidambar) communities with 506 g m-2 yr-1 and 455 g m-2 yr-1, respectively. Litter nutrient concentrations were generally higher in the cypress and maple-gum stands, indicating greater nutrient availability …


The Flora And Sandhills Prairie Communities Of Arapaho Prairie, Arthur County, Nebraska, Kathleen H. Keeler, A. T. Harrison, L.S. Vescio Sep 1980

The Flora And Sandhills Prairie Communities Of Arapaho Prairie, Arthur County, Nebraska, Kathleen H. Keeler, A. T. Harrison, L.S. Vescio

School of Biological Sciences: Faculty Publications

The Arapaho Prairie is a 526-hectare (two-section) tract of upland Sandhills prairie located approximately nine miles southwest of the town of Arthur in Arthur Co., Nebraska (Sec. 31, 32 T18N R39W). The Prairie is at the extreme southwest edge of the 52,000-km2 Nebraska Sandhills (see Kaul 1975) and is floristically and ecologically typical of the slightly drier, western part of this vegetation type. Sandhills prairie which stretches across much of north central Nebraska is a unique type of "mixed" grassland (Pool 1914, Rydberg 1931, Tolstead 1942, Weaver 1965) created by impact of the dry, continental climate on the extensive …


Muskrat Population Dynamics And Vegetation Utilization: A Management Plan, Thomas R. Mccabe, Michael L. Wolfe Aug 1980

Muskrat Population Dynamics And Vegetation Utilization: A Management Plan, Thomas R. Mccabe, Michael L. Wolfe

Aspen Bibliography

Muskrat (Ondatra zibethicus) populations are located in extensive marshes that are managed either privately or by state or federal refuge personnel. Maintenance of a balanced muskrat population is important to marsh management, therefore necessitating accurate density estimates. Feasibility of a vegetational utilization index as a reliable population indicator is being tested at Fish Springs NWR, Utah.


Roadside Zoos Are Not Zoos Aug 1980

Roadside Zoos Are Not Zoos

Close Up Reports

The HSUS was one of the first national animal welfare organizations to take a long, hard look at all zoos, including roadside menageries. During the last nine years, we have worked intensively, conducting zoo inspections, public education and awareness programs, and developing a working relationship with the professional zoological community as well as U.S. Government agencies charged with the welfare of animals.


The Possible Influence Of Nestbox Size On Nesting Behavior And Reproductive Success In The House Wren (Troglodytes Aedon), Mary Anne Sydlik Aug 1980

The Possible Influence Of Nestbox Size On Nesting Behavior And Reproductive Success In The House Wren (Troglodytes Aedon), Mary Anne Sydlik

Masters Theses

Recent studies (Lohrl 1973i Karlsson and Nilsson 1977) have shown that there may be a relationship between nestbox size and clutch size in several passerine species. The present study was designed to determine whether nestbox size influences the clutch size and reproductive success of House Wrens (Troglodytes aedon) and to test possible cues a female might utilize to assess the size of a given nestbox. Four types of nestboxes were used in the study; they varied in floor surface from 3 inches by 3 inches to 8 inches by 8 inches. No statistically significant differences in clutch size or reproductive …


A Limnological Investigation Of A Tropical Fresh-Water Ecosystem: The Belize River, Belize, Central America, Victor J. Gonzalez Aug 1980

A Limnological Investigation Of A Tropical Fresh-Water Ecosystem: The Belize River, Belize, Central America, Victor J. Gonzalez

Dissertations

The limnology of the Belize River, from the region of Spanish Lookout to the region of Belize City, was investigated from 1977 through 1979. The investigation was done primarily during the months of May through August, covering the two seasonal changes--wet and dry--that occur in this tropical region. The investigation sought to describe various parameters of the Belize River so as to gain an understanding of this tropical fresh-water ecosystem and to provide basic information needed for the development of management programs.

Water samples were collected from eight stations and analyzed for acidity, alkalinity, carbon dioxide, chloride, sodium chromate, hexavalent …


Results Of The Alcoa Foundation-Suriname Expeditions. Iii. Chromosomal Data For Bats (Mammalia: Chiroptera) From Suriname, Rodney L. Honeycutt, Hugh H. Genoways, Robert J. Baker Jul 1980

Results Of The Alcoa Foundation-Suriname Expeditions. Iii. Chromosomal Data For Bats (Mammalia: Chiroptera) From Suriname, Rodney L. Honeycutt, Hugh H. Genoways, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

Standard karyotypic data are presented for 28 species involving 98 specimens. The karyotype of Micronycteris sylvestris, M. daviesi, Phyllostomus latifolius, and Tonatia schulzi are reported for the first time. Chromosomal variation is described for Rhinophylla pumilio and Rhogeessa tumida. Karyotypes for the other species examined were like those previously described in the literature.


Results Of The Alcoa Foundation-Suriname Expeditions. 1. A New Species Of Bat Of The Genus Tonatia (Mammalia: Phyllostomatidae), Hugh H. Genoways, Stephen L. Williams Jul 1980

Results Of The Alcoa Foundation-Suriname Expeditions. 1. A New Species Of Bat Of The Genus Tonatia (Mammalia: Phyllostomatidae), Hugh H. Genoways, Stephen L. Williams

University of Nebraska State Museum: Mammalogy Papers

new species of the phyllostomatine genus Tonatia is described from Suriname. The species is characterized by medium size, the presence of small wart-like granulations of the dorsal surfaces of the forearm, digits, and hind limbs and on the ears and noseleaf, and possessing a unique karyotype. Two specimens of the species were taken in the rainforests of central Suriname.


Results Of The Alcoa Foundation-Suriname Expeditions. Ii. Additional Records Of Bats (Mammalia: Chiroptera) From Suriname, Stephen L. Williams, Hugh H. Genoways Jul 1980

Results Of The Alcoa Foundation-Suriname Expeditions. Ii. Additional Records Of Bats (Mammalia: Chiroptera) From Suriname, Stephen L. Williams, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

The occurrence of 14 species of bats previously unknown in Suriname are documented, making a total of 85 species of bats known to occur in the country. The new records include Pteronotus personatus, Chrotopterus auritus, Micronycteris daviesi, M. sylvestris, Phyllostomus latifolius, Choeroniscus godmani, C. intermedius, Lionycteris spurrelli, Mesophylla macconnelli, Vampyressa brocki, Vampyrops brachycephalus, Rhogeessa tumida, Molossops abrasus, and M. greenhalli. Additional information is provided on several species of bats already known to occur in Suriname, including Micronycteris minuta, M. nicefori, Phylloderma stenops, Tonatia …


A Review Of The Behavioural Mechanism Of Milk Ejection Of The Domestic Pig, David Fraser Jul 1980

A Review Of The Behavioural Mechanism Of Milk Ejection Of The Domestic Pig, David Fraser

Feeding Behavior Collection

The domestic pig has complex nursing and suckling behaviour, consisting of several distinct phases of suckling by the piglets and a characteristic pattern of grunting by the sow. A review of observations and experimental findings suggests cause-and-effect relationships between the different elements of sow and piglet behaviour, and the relationship of the behaviour to milk ejection. Characteristic features of pig nursing and suckling behaviour are interpreted as an adaptation promoting even distribution of milk among a number of precocious litter-mates.


Sampling Problems And Interpretation Of Chemical Analysis Of Mineral Springs Used By Wildlife, D. Fraser, E. Reardon, F. Dieken, B. Loescher Jul 1980

Sampling Problems And Interpretation Of Chemical Analysis Of Mineral Springs Used By Wildlife, D. Fraser, E. Reardon, F. Dieken, B. Loescher

Habitat Assessment and Management Collection

Mineral-rich springs used by wildlife were studied in order to develop an appropriate sampling technique. The mineral content of the water varied spatially within a lick, apparently because of contamination by nonlick water and animal urine. The spring source usually could be located with a conductivity meter. Samples contaminated by animal urine could be recognized by their high N content and usually by their color. The distinctive chemical composition of licks is best appreciated by comparing filtered samples of lick water with nonlick water collected nearby. Field filtration was necessary when samples were preserved with acid for trace-metal analysis. Soil …


The Prairie Naturalist Volume 12, Number 2. June 1980 Jun 1980

The Prairie Naturalist Volume 12, Number 2. June 1980

The Prairie Naturalist

COMPOSITION OF BEAVER CACHES ON THE TONGUE RIVER IN MONTANA ▪ J. E. Swenson and S. J. Knapp

GRAY PARTRIDGE WINTER MOVEMENTS AND HABITAT USE IN NORTH DAKOTA ▪ J. W. Schulz

ANNOTATED CHECKLIST OF MAMMALS OF NEBRASKA ▪ J. K. Jones, Jr. and J. R. Choate

OBSERVATIONS OF SEVERAL ARCTIC GULLS IN NORTH DAKOTA ▪ C. A. Faanes and T. A. Gatz

WINTER FOOD HABITS OF NEBRASKA BOBCATS (Felis rufus) C. J Mahan

NOTE

The Meadow Jumping Mouse in Southeastern Montana ▪ W. L. Matthews


The Section Of Mammals Of Carnegie Museum Of Natural History, Hugh H. Genoways, Duane A. Schlitter Jun 1980

The Section Of Mammals Of Carnegie Museum Of Natural History, Hugh H. Genoways, Duane A. Schlitter

University of Nebraska State Museum: Mammalogy Papers

The Section of Mammals at Carnegie Museum of Natural History is responsible for the care of the collections of Recent mammals, and research on these collections. "Recent mammals?!" The capitalized word "Recent" refers to the geological time period since the last ice age (about 10,000 years ago) until the present time. Mammals are that group of animals characterized by the presence of hair at least during some time of their lives, warm blood, and the production of milk. Therefore, our work really involves living mammals with which everyone is familiar; however, our work also does include study of such recently …


Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson Jun 1980

Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson

Publications (WR)

Density currents are commonly formed in reservoirs because of temperature or salinity induced density differences between inflowing and receiving waters. Anderson and Pritchard (1951) were among the first to demonstrate this in their investigations of density currents in Lake Mead. They found that the Colorado River formed an underflow in Lake Mead during the winter, an overflow in the spring and an interflow in the summer and fall. Wunderlich and Elder (1973) have since described the hydromechanics of these types of flow patterns, and density currents have been reported for several other large reservoirs (Carmack et al. 1979, Johnson and …


Nutrient Interactions Among Reservoirs On The Colorado River, Larry J. Paulson, John R. Baker Jun 1980

Nutrient Interactions Among Reservoirs On The Colorado River, Larry J. Paulson, John R. Baker

Publications (WR)

Interactions among physical, chemical and biological processes in reservoirs can significantly alter the characteristics of the discharge (Neel 1963, Wright 1967, Hannan 1979) that, in turn, can influence the ecology of the river downstream .(Ward and Stanford 1979). Investigations of the Colorado River, system reveal that reservoir-induced changes in the river can also affect downstream reservoirs. The formation of Lake Powell, in 1963 was accompanied by reductions in suspended sediment and nutrient loading and changes in the seasonal temperature and discharge cycles of the Colorado River. In this paper, we evaluate how these changes have influenced the nutrient and trophic …


Demographic And Reproductive Parameters Of The Yellow-Cheeked Pocket Gopher (Pappogeomys Castanops), Michael J. Smolen, Hugh H. Genoways, Robert J. Baker May 1980

Demographic And Reproductive Parameters Of The Yellow-Cheeked Pocket Gopher (Pappogeomys Castanops), Michael J. Smolen, Hugh H. Genoways, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

A population of Pappogeomys castanops simulans was live-trapped on a 3.5-ha study area in Lubbock, Texas, from September 1971 to September 1973. Seasonal and annual differences in population size were observed, with the population fluctuating between 20 and 25 gophers. Female reproductive activity began in January and continued until October, with an obvious period of recruitment lacking; however, a peak was observed in March and April. Females produced as many as three litters per reproductive season. Females born early in the year were sexually mature within the reproductive season of their birth. Females had an average survival rate of 56 …


An Agro-Sylvo-Pastoral Approach To Desertification Control And Increased Productivity Of The Sahel, Rober D. Kirmse May 1980

An Agro-Sylvo-Pastoral Approach To Desertification Control And Increased Productivity Of The Sahel, Rober D. Kirmse

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The southern arid fringe of the Sahara Desert, called the Sahel, is progressively becoming less productive through a systematic deterioration of the environment. Population increases and technological advances have encouraged ecological degradation through man's normal activities for survival. The degradation process has been referred to as desertification, desertization, desert encroachment, and desert creep.


Evolutionary Origin Of Eptesicus Lynni, Michael L. Arnold, Robert J. Baker, Hugh H. Genoways May 1980

Evolutionary Origin Of Eptesicus Lynni, Michael L. Arnold, Robert J. Baker, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Currently, three species of bats of the genus Eptesicus (fuscus, guadeloupensis, and lynni) are recognized as occurring on islands in the Antilles. Of these, E. fuscus and E. guadeloupensis are believed to belong to the fuscus-group of the genus (Davis, 1966; Genoways and Baker, 1975). However, the status and relationships of E. lynni are unclear. Shamel (1945) described lynni as a member of the brasiliensis-group. On the other hand, Sanbom (1941) considered three earlier specimens of lynni as members of the subspecies E. fuscus hispaniolae (we have examined the Sanbom specimens and they are referable to …


Resource Partitioning In Breeding Populations Of Marsh Hawks And Short-Eared Owls, Susan C. Linner May 1980

Resource Partitioning In Breeding Populations Of Marsh Hawks And Short-Eared Owls, Susan C. Linner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the 1979 breeding season four pairs of northern harriers, or marsh hawks (Circus cyaneus) and four pairs of short-eared owls (Asio flammeus) were studied in Cache Valley, Utah. The study was concerned solely with diurnal resource utilization, and did not examine the owls' nocturnal activities. The home range of each harrier pair overlapped substantially with that of an owl pair. Percent habitat overlap for hawk-owl pairs varied from 39 percent to 72 percent. Observations were made to determine if differences existed in their utilization of habitat and food resources, or in their daily and seasonal …


An Analysis Of A Measure Of Productivity In Mule Deer Populations, Ronald J. Ryel May 1980

An Analysis Of A Measure Of Productivity In Mule Deer Populations, Ronald J. Ryel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to investigate the relationship between the fall proportion of fawns among fawns and does in a mule deer population and two measures of productivity, the spring recruitment rate and the reproductive performance as measured in the fall. The spring recruitment rate was defined to be the number of fawns per doe which were recruited into the population at 1 year of age. The reproductive performance was defined to be the number of fawns produced per doe 2 years or older which survive to a specified time. The relationships between these quantities were measured by …


The Effect Of Exploitation On Some Parameters Of Coyote Populations, Robert P. Davison May 1980

The Effect Of Exploitation On Some Parameters Of Coyote Populations, Robert P. Davison

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study was conducted to examine the effect of exploitation on population parameters of coyotes (Canis latrans). Hypotheses tested were: (1) Substantial levels of exploitation do not change spring and fall coyote densities significantly; (2) Coyote recruitment (reproduction and immigration) rates are unaffected by substantial levels of exploitation; (3) Annual coyote survival rates are not related to intensity of harvest rates; (4) Coyote emigration rates remain unchanged by substantial levels of exploitation. Coyote demographic parameters were measured from 1975 to 1978 for a treatment population subject to substantial exploitation (Curlew Valley, Utah and Idaho), and for an unexploited …


Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire May 1980

Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the present study was to investigate how plant spatial patterns and insect behavior interact to influence the population dynamics of insects using the plants. The study included three phases: l) field experiments using collards (Brassica oleracea) and the crucifer insect fauna; 2) simulation models representing the population dynamics of an insect herbivore as functions of insect dispersal behavior and host plant patch size; and 3) model-field syntheses integrating model predictions and field variability estimates to choose an appropriate spatial scale for future field experiments or applications.

In field experiments on surrounding plant type, collards were …


Production Of Mountain Whitefish (Prosopium Williamsoni) In Altered And Unaltered Reaches Of Two Intermountain Streams In Their Alluvial Flood Plains, Michael J. Ottenbacher May 1980

Production Of Mountain Whitefish (Prosopium Williamsoni) In Altered And Unaltered Reaches Of Two Intermountain Streams In Their Alluvial Flood Plains, Michael J. Ottenbacher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Estimates of production and related parameters (growth rate, density, standing crop) were made for populations of mountain whitefish in altered and "unaltered" areas of the Blacksmith Fork and Logan River, Utah from spring 1975 through summer 1976. Capture records of marked whitefish were also analyzed to describe fish movement and check on assumptions implicit in the population estimator.

Mean weights and instantaneous growth rates of whitefish were similar at all sites for comparable size/age groups. Among sites, differences in production per sampling interval and annual production were due mainly to differences in standing crop and/or age structure.

Estimates of mountain …


The Social Ecology Of Coyotes, Marc Bekoff, Michael C. Wells Apr 1980

The Social Ecology Of Coyotes, Marc Bekoff, Michael C. Wells

Ethology Collection

No abstract provided.


Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne Apr 1980

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …


The Feasibility Of Commercial Scale Culture Of Atlantic Sturgeon, Acipenser Oxyrhynchus, Christopher John Coffing Apr 1980

The Feasibility Of Commercial Scale Culture Of Atlantic Sturgeon, Acipenser Oxyrhynchus, Christopher John Coffing

Biological Sciences Theses & Dissertations

Abstract unavailable.


Percina Gymnocephala, A New Percid Fish Of The Subgenus Alvordius, From The New River In North Carolina, Virginia, And West Virginia, Eugene C. Beckham, Iii Mar 1980

Percina Gymnocephala, A New Percid Fish Of The Subgenus Alvordius, From The New River In North Carolina, Virginia, And West Virginia, Eugene C. Beckham, Iii

Occasional Papers of the Museum of Natural Science, Louisiana State University

No abstract provided.


Mountain Beaver Problems In The Forests Of California, Oregon And Washington, John E. Borrecco, Robert J. Anderson Mar 1980

Mountain Beaver Problems In The Forests Of California, Oregon And Washington, John E. Borrecco, Robert J. Anderson

Vertebrate Pest Conference Proceedings: 9th (1980)

Mountain beavers (Aplodontia rufa) cause considerable damage to forest trees in the Pacific Northwest. Feeding injuries result in mortality, growth losses, deformity of trees, and understocked plantations. Losses are most severe in new plantations with significant damage problems also occurring in sapling stands. Trapping, and placing physical barriers around individual trees, are the most common methods of control. Both methods are costly but effective in reducing damage.


Metabolism And Solar Radiation In Dark And White Herons Nesting In Hot Climates, Hugh I. Ellis Mar 1980

Metabolism And Solar Radiation In Dark And White Herons Nesting In Hot Climates, Hugh I. Ellis

Biology: Faculty Scholarship

Metabolism, body temperature (Tb), and feather reflectance was measured for dark Louisiana herons (LOU), little blue herons (LB), snowy egrets (SE), and cattle egrets (CE); only LOU nest preferentiallyin shade. The reflectance of LOU and adult LB was 13%-15%; it was 80%-82% for SE, CE, and immature (white) LB. Tb for all four species approximated 40 C; hypothermy was never observed. Basal metabolism (HJb) was 107% of the expected level for LOU, 85% for SE and CE, and 66% for LB. Minimal thermal conductance (C) was calculated as approximately 131% of the expected value for LOU, 115% for SE and …


The Prairie Naturalist Volume 12, Number 1. March, 1980 Mar 1980

The Prairie Naturalist Volume 12, Number 1. March, 1980

The Prairie Naturalist

RESIDUAL SEEDS AS POTENTIAL SPRING WATERFOWL FOODS IN SMALL, MAN-MADE IMPOUNDMENTS ▪ G. A. Baldassarre

NOTES ON THE NATURAL HISTORY OF BATS FROM BADLANDS NATIONAL MONUMENT, SOUTH DAKOTA ▪ J. P. Farney and J. K. Jones, Jr.

PRAIRIE CHICKEN DOMINATED SHARP-TAILED GROUSE INTERACTION ▪ R. A. Schmidt

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA— 1979 ▪ R. N. Randall

THIRD NESTING OF CATTLE EGRET IN NORTH DAKOTA ▪ R. A. Schmidt

FIRST BREEDING RECORDS OF THE WHITE-FACED IBIS IN NORTH DAKOTA ▪ R. A. Schmidt

NOTES

Pinon Jay in North Dakota ▪ R. N Randall, J. Swanick and O. Swanick

Gray-crowned …