Terrestrial and Aquatic Ecology 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 …

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, …

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 …

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 …

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 …

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 …

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 …

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.