Life Sciences Commons^™

Diversity Of Coprophagous Scarabaeidae (Coleoptera) In Grazed Versus Ungrazed Sandhills Prairie In Western Nebraska, Mary Liz Jameson

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Baited pitfall traps were used to compare the dung-feeding Scarabaeidae (Coleoptera) of a grazed versus an ungrazed sandhills prairie in western Nebraska. Traps yielded 14,832 coprophagous Scarabaeidae over a 4-week sampling period in 1987. Canthon ebenus (Say), C. pilurarius (L.), Onthophagous hecate Panzer, and O. pennsylvanicus Harold were the dominant species on both prairies. The Shannon-Wiener diversity index indicated that diversity was slightly higher on the grazed site whereas the Margalef diversity index showed the diversities to be nearly the same. Activity and foraging by scarabs (as measured by trapping success) were found to be most closely correlated with temperature …

Woody-Plant Succession In An Eastern Nebraska Bluff Forest, Douglas E. Borland, Thomas B. Bragg, David M. Sutherland

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Woody plant composition of ridgetop old-fields abandoned at various times since 1800 suggest a successional pattern for an eastern Nebraska bluff forest. Sites abandoned for 24 years were dominated by elm (Ulmus spp.) and rough-leaved dogwood (Comus drummondii). Other sites, abandoned for76 years, were dominated by bitternut hickory (Cwya cordijormis), American linden (Tilia americana), and hop-hombeam (Ostrya virginiana), and those abandoned for 186 years were predominantly bur oak (Quercus macrocarpa) and hop-hornbeam. Based on species importance values, we conclude that the composition of this forest is still changing.

The Biology And Ecology Of The Tiger Beetles (Coleoptera: Cicindelidae) Of Nebraska, Mark R. Carter

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Nebraska has a large and diverse Cicindelidae fauna. This paper lists three genera and 32 species and subspecies as occurring in the State. The large number of species can be attributed to the number of physiographic regions (six) found in the State. Distinct topographic, floristic, and climatic features found in the regions have created a large number of favorable habitats for tiger beetles. This paper presents information on the biology and ecology of the species of tiger beetles found in Nebraska as related to the physiographic regions in the State. Morphological descriptions, line drawings, and a key are presented to …

Effects Of Substrate On Density Of Aquatic Insects In A Southeast Nebraska Stream, Patrick O. Darrow, Kenneth P. Pruess

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Effects of artificial substrate on aquatic insect density were studied in Haines Branch, Lancaster County, Nebraska. Treatments consisted of small, medium,large, and mixed (mixture of small and medium) concrete substrates in modified basket samplers. Three replicates of each treatment were removed at 14 and 28 days and aquatic insects were then enumerated. Insects collected were chironomids (63%), mayflies ( 19%), caddisflies (15%), and beetles (3%). Mean mayfly densities, averaged over all substrate treatments, were higher on day 28 than on day 14, while the reverse was observed for chironomid densities. Mean densities for mayflies and chironomids were higher in medium …

Birds Of The Niobrara River Valley, Nebraska, James E. Ducey

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

This review and compilation of available published material and personal observations of several people outlines the specific range and status of bird species in the Niobrara River Valley. There are several biotic communities represented by pine forest, deciduous forest, prairie, wetland meadow, marsh, river channel, and others. The diversity of the Valley floristic communities provides habitat for a unique mix of avifauna. More than 250 species have been recorded in the Valley between the Wyoming state line and the junction of the Missouri River. Also discussed is avian hybridization and population information for some species. About 25 species are recognized …

Persistence Of A Chemical Gradient In The Lower Platte River, Nebraska, Richard S. Holland, Edward J. Peters

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

During a 1986-87 study of microhabitat utilization by Platte River fauna we noted a persistent difference in conductance between north and south banks. A series of transects across the river, measured on 11 August 1987, between River Miles 78-59, demonstrated that the conductivity gradient persisted throughout the 32 km study segment. Typical readings were 315 umhos cm^-1 for the north side and 550 umhos cm^-1 for the south side. Additional upstream measurements showed that the gradient originates at the confluence of the Platte River and the Loup River Power Canal (RM 101). Upstream, the Platte River mean monthly …

The Quest Of Dr. Ernest F. Bashford For Knowledge About Cancer Etiology In Man And Mouse, Anne J. Krush

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Dr. Ernest F. Bashford, an English physician,lived from 1873 to 1923. For many years before his untimely death, he was an officer for the Imperial Cancer Research Fund. From articles in the British Medical Journal and other publications, Bashford prepared a volume of reprints (1903-1909) concerning problems, growth, and heredity of cancer, and experiments with breast cancer in mice. Cancer had been studied histologically and clinically, with only speculation as to its origin, nature, and cause in man. He suggested cooperative studies by investigators in many different fields. Concerned with why the growth of cancer seemed limitless, and with problems …

Range Extensions For Some Nebraska Bryopbytes, Linda L. Spessard

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Range extensions are presented for seven species of mosses in Nebraska: Amblystegium serpens, Brachythecium oxycladon, Bryum caespiticium, B. capillare, Ephemerum cassinervum, Orthotrichum pumilum, and O. stellatum. Six new county records are listed.

Transactions Of The Nebraska Academy Of Sciences Volume Xvii (1989): Table Of Contents

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Editorial Contents

Nebraska Academy of Sciences, Officers, Policy Committee .......... ii

Editorial Board .......... v

Membership Objectives and Friends of the Academy .......... vi

Biological Sciences

The biology and ecology of the tiger beetles (Coleoptera: Cicindelidae) of Nebraska (Mark R. Carter) .......... 1-18

Effects of substrate on density of aquatic insects in a southeast Nebraska stream (Patrick O. Darrow and Kenneth P. Pruess) .......... 19-22

Distribution of Amoebidium and Smittium species (Trichomycetes) in mosquito larvae on the Platte River floodplain of central Nebraska (Roger D. Grigg and Marvin C. Williams) .......... 23-28

Diversity of coprophagous Scarabaeidae (Coleoptera) in grazed versus …

Propagation Of Blowout Penstemon (Penstemon Haydenii S. Watson): Germination-Enhancing Treatments, Theresa R. Flessner, James L. Stubbendieck

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Development of germination-enhancing treatments will be essential for the recovery of Nebraska's only officially endangered plant species, blowout penstemon (Pensiemon haydenii S, Watson), Effects of cold-moist stratification, mechanical or chemical scarification, and presence or absence of light in combination with alternating temperature regimes on seed germination of blowout penstemon was determined by laboratory studies. Stratified seeds exhibited greater mean germination percentages (21 %) than nonstratified seeds (8%). Effects of mechanical scarification on germination varied with trial. Seeds chemically scarified with concentrated sulfuric acid exhibited greater mean germination percentages (48%) than controls (12%); such scarification may substitute for the effective, …

Chemical And Physical Characteristics Of The Missouri River, Nebraska, Larry W. Hesse, Gerald E. Mestl, Marla J. Rohrke

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Selected physical and chemical parameters were observed at the following sites: unchannelized and channelized main-channel Missouri River, an unchannelized backwater, and 13 tributaries of the Missouri River during the period 1985 through 1988. Mean main-channel discharge is artificially maintained at a higher rate during winter since construction of the main-stem dams. The mean flow through a remnant backwater in an unchannelized reach represents about 3.1% of the main-channel discharge. Turbidity is much reduced from the pre-dam period and is highest during the March and June periods of high discharge. Specific conductance in the main channel was measured as high as …

The Status Of Erythronium Albidum And E. Mesochoreum (Liliaceae) In Nebraska, Robert B. Kaul

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Two species of Erythronium grow in the eastern quarter of Nebraska, but there are none elsewhere in the State. Erythronium albidum is locally abundant, mostly in upland bur oak forests, and has been collected in 18 counties since 1864. Erythronium mesochoreum is becoming rare because its habitat--virgin tall-grass prairie--is disappearing. It is known to grow now in six east-central counties, but it probably could be found in some remnant prairies in all counties south and east of the Platte and Big Blue rivers, respectively. Distributional data about these species is herein brought up to date relative to earlier published reports. …

An Annotated List Of The Vascular Plants Of Keith County, Nebraska, David M. Sutherland, Steven B. Rolfsmeier

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

This study provides an annotated list of the vascular plants known to exist outside of cultivation in Keith County, Nebraska. Listed are a total of 599 species, subspecies and varieties belonging to 302 genera of 87 families. Notes are included about frequency and habitat for each of the taxa. 264 (44.1 %) of the taxa listed were previously unreported for Keith County. Additionally, the paper discusses vegetation regions in the county and gives information in tabular form about numbers of the flora in different taxa, the ten largest families, numbers of taxa of different growth habits, and numbers of taxa …

Distribution Of Amoebidium And Smittium Species (Trichomycetes) In Mosquito Larvae On The Platte River Floodplain Of Central Nebraska, Roger D. Grigg, Marvin C. Williams

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Trichomycetes (fungi) inhabit the digestive tract of insects and other arthropods. Two genera. Smittium and Amoehidium, were collected from mosquito larvae (Culicidae) from 36 sites in a six-county area of central Nebraska, U.S.A., in the Platte River floodplain during the summers of 1986 and 1987. When present, thirty mosquito larvae per site per month were identified at the fourth instar, checked for the epizooite A. parasiticum, and then dissected and the gut examined by phase-contrast microscopy for S. culisetae and S. culicis. In 1986, 17 species of mosquito larvae from six genera (n = 665) were dissected …