Life Sciences Commons^™

Karyology And Morphometrics Of Three Species Of Akodon (Mammalia: Muridae) From Northwestern Argentina, Rubén M. Barquez, Daniel F. Williams, Michael A. Mares, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Chromosomal and morphometric studies were conducted on a sample from an assemblage of Akodon spp. occurring in various patterns of sympatry from the provinces of Catamarca, Jujuy, Salta, and Tucumán, Argentina. Results showed three distinct morphometric groups based upon size. Size also varied with age, but there were no significant differences in measurements of males and females. The three morphometric groups have distinct karyotypes. Akodon caenosus Thomas is the smallest of the three, and has a karyotype of 2n = 34, FN = 40. A. boliviensis tucumanensis J. A. Allen is intermediate in size and has 2n = 40, FN …

Methods For Biological, Chemical, And Physical Analyses In Reservoirs, Penelope E. Kellar, Sherell A. Paulson, Larry J. Paulson

Publications (WR)

This manual contains detailed descriptions of biological, chemical and physical sampling and analytical procedures used at the Lake Mead Limnological Research Center. The manual was prepared in response to requests made by numerous individuals involved in the Las Vegas Valley Water Quality Program. This manual represents what we consider to be a reasonably complete compilation of methods useful in studying both general and specific limnological questions. While each section is sufficiently detailed to be of use to investigators with little experience in limnological methodology, the methods can be used on a wide variety of lakes and reservoirs, with relatively little …

Seasonal Variations In Water Chemistry And Primary Productivity In Four Alkaline Lakes In The Sandhills Of Western Nebraska, John A. Schnagl

Open Access Master's Theses (through 2010)

Between the Platte and Niobrara Rivers in western and central Nebraska lie over 25,000 square kilometers of dune sand. The dunes have lost their sculptured shapes and windswept edges, being shrouded beneath a mantle of grass and fine loess soil. Only at the blowouts, where wind has cut away this mantle forming cavities in the sides of hills, is the sand exposed.

Dotting this rolling prairie grassland in the depressions between the dunes are small lakes. Over 2000 lakes of widely varied salinities and alkalinities accent the topography of the dunes.

Blue Lake, Roundup Lake, Goose Lake, and Bob’s Lake, …

James City County Tidal Marsh Inventory, Kenneth A. Moore, Gene M. Silberhorn

Reports

No abstract provided.

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 …

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 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

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

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

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 …

Developing Crab Creek : Fifteen Points Of View On Economy And Ecology In An Estuary : A Simulation For Advanced Students Exploring Coastal Resource Management Decisions In Virginia, Frances Lee Lawrence

Reports

Crab Creek County is a hypothetical small Virginia county on. the Chesapeake Bay. This· simulation explores the coastal management issues involved in developing a point of land in Crab Creek County fronting on the Chesapeake Bay to the North, and Crab Creek to the South. The game is based on key Virginia and federal laws and agencies affecting coastal resources, and provides insights into the human and technical interactions involved in the "permitting" processes. Players fill fifteen roles representative of private interests as well as local, state, and federal activities. more...

Notes On The Natural History Of Bats From Badlands National Monument, South Dakota, John P. Farney, J. Knox Jones Jr.

University of Nebraska State Museum: Mammalogy Papers

Little has been published on the mammalian fauna of Badlands National Monument, a unique ecological area that encompasses parts of Jackson and Pennington counties in South Dakota. By way of example, although five species of bats are herein recorded from the Monument, only one has been reported previously - see Jones and Choate (1978), who listed two specimens of Myotis thysanodes pahasapensis from the Cliff Shelf area. Jones and Genoways (1976b), however, did report several other species from badland areas not far distant from the boundary of the Monument.

In 1970, under sponsorship of the Badlands Natural History Association and …

Evaluation Of Impacts Associated With Reregulation Of Water Levels In Lake Mohave, Larry J. Paulson, John R. Baker, U.S. Water And Power Resources Service

Publications (WR)

The U.S. Water and Power Resources Service is considering reregulating Lake Mohave water levels to increase the net power benefit from Hoover Dam. Reregulation will not increase the generation capacity of the Hoover powerplant but it will enable the plant operation to be increased when the energy has greater monetary value. Energy generated at different times of the year has different market value, the highest being in January-March and July- September. By generating more power during these periods more net monetary benefit can be derived from Hoover Dam. The total volume of water released from Hoover Dam over an annual …

Nebraska Trapping, George Schildman, Frank Andelt, Jim Brunner

Nebraska Game and Parks Commission: Publications

Fur bearers and trapping played an important role in the exploration and development of Nebraska. The harvest of our fur-bearer resource is part of every Nebraskan's heritage. Wise use of the resource and consideration for other people's property and personal rights can insure that trapping will remain a part of the heritage of future generations. The purpose of this publication is to help insure this heritage ... through the educational process. Knowledge of and respect for the resource, as well as consideration for other people, are the keys to perpetuating trapping as an outdoor activity. While primarily designed to assist …

Dickey-Lincoln School Lakes Project Environmental Impact Statement: Appendix K: Fish & Wildlife Mitigation Plan & Impacts (Revised), New England Division, United States Army Engineer Division

Dickey-Lincoln School Lakes Project

The proposed plan is comprised of three major segments: terrestrial, fisheries and endangered species. Each segment is essentially a self-contained unit. All costs for the three segments including land acquisition, operation and maintenance and capital equipment, are to be charged to the project and allocated to the project purposes of hydroelectric generation and flood control.

Influence Of Dredging And High Discharge On The Ecology Of Black Canyon, Larry J. Paulson, Theron G. Miller, John R. Baker, U.S. Water And Power Resources Service

Publications (WR)

The Water and Power Resources Service is considering dredging in Black Canyon to create a larger forebay to accommodate higher peak discharges and reverse flows for proposed modifications to Hoover Dam.

The Black Canyon area from Hoover Dam to Willow Beach supports a heavily utilized trout fishery and is important habitat for the razorback sucker (Xyrauchen texanus) and possibly bonytail chub (Gila elegans).

The Water and Power Resources Service initiated this investigation to determine what effect dredging and higher peak-discharges would have on the ecology of Black Canyon.

Population Regulation In Wolves, Jane M. Packard, L. David Mech

USGS Northern Prairie Wildlife Research Center

The possibility of social regulation of wolf populations has been discussed in the literature for several years. Some of the first ecological studies of wolves indicated that their populations did not increase as rapidly as was theoretically possible, and that they reached a saturation point apparently not set by food. Subsequent captive studies demonstrated the existence of social mechanisms possibly capable of regulating population growth. However, the importance of these factors in wild populations has not been established. This paper has four objectives: (1) to evaluate the existing concept of "intrinsic limitation," (2) to propose that wolf population dynamics may …

Apparent Chromosomal Heterosis In A Fossorial Mammal, John C. Patton, Robert J. Baker, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

For the past decade, numerous investigators have attempted to explain the plethora of genetic polymorphism found in nature (see Ayala 1976). However, few researchers have been able to document how polymorphisms have been maintained, whether the polymorphisms were genic or chromosomal. Our investigations into the maintenance of a Robertsonian chromosomal polymorphism in the plains pocket goher, Geomys bursarius major, have revealed evidence that this polymorphism is maintained by differential viabilities of the three chromosomal morphs, with the heterozygote being favored.

Estimate Of The Total Weight Of Kepone In The Major Components Of The Molluscan Fauna Of The James River, Virginia, Dexter S. Haven, Reinaldo Morales-Alamo

Reports

Contamination of the James River in Virgin ia with the pesticide Kepone has resulted in its accumulation in the tissues of the fauna inhabiting the river. Most of the Kepone available to the biota in the river is associated with sediment s (Schneider and Dawson, 1978) and Haven and Morales-Alamo (1979) have shown that oysters and other bivalve molluscs accumulate Kepone in their tissues when exposed to the pesticide associated with sediments in suspension. It is of interest to compare the quantities of Kepone bound in James River sediments with the quantities bound in the molluscan fauna of the river.

Perkinsus Marinus = Dermocystidium Marinum ("Dermo") In Virginia, 1950-1980 : A Record Of Fluid Thioglycollate Tests For Dermo In Oysters From Public And Private Oyster Beds, And From Trays Of Disease-Free Oysters Transplanted To Areas Where Msx And Dermo Are Endemic, Jay D. Andrews

Reports

No abstract provided.