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Distribution Of Zooplankton In Harlan County Reservoir, Nebraska, Kathy M. Maline, Keith D. Koupal, Brian C. Peterson, W. Wyatt Hoback

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The objective of this study was to determine the horizontal and vertical distribution of zooplankton in Harlan County Reservoir in order to assist in developing an appropriate zooplankton sampling regime for this and similar Nebraska irrigation reservoirs. Samples were collected at 16 sites distributed across 3 zones of the reservoir monthly in April, May, June, and July of 2007 using a 2.2 L Van Dorn sampler. Samples were collected at depths of 1, 4, and 7 meters, poured through an 80-μm filter, preserved, and identified to the lowest possible taxa. Total zooplankton densities in Harlan County Reservoir were statistically similar …

Assessment Of Water Quality And Response Rate Of Zooplankton In A Nebraska “Barrow Pit” After Rotenone Application, Brian C. Peterson, Byron W. Sellers, Nicolas J. Fryda, Keith D. Koupal

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Understanding the extent and depth of rotenone impacts on all trophic levels is essential to effective aquatic management. We examined changes in water quality tenets and zooplankton communities following the establishment of 3 ppm rotenone concentration in a Nebraska barrow pit. Dissolved oxygen initially decreased 57% and subsequently increased 298% the week following rotenone application. Turbidity decreased from 25.8 FAU ± 0.80 pre-treatment to 6.6 FAU ± 0.98 one year later. Total zooplankton (0.17/L ± 0.03) were limited prior to rotenone application and absent for the following 3 weeks. One year later the total number of zooplankton increased 1024%, and …

The Vascular Flora Of Brown County, Nebraska, Megan K. Killion, Steven J. Rothenberger

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Brown County, located in north-central Nebraska contains several native vegetation types including sand hills mixed-grass prairie, gravelly mixed-grass prairie, ponderosa pine forests/savannas, sand hills-borders/mixed-grass prairie, upland deciduous forest, and wet lands. The Nebraska Sand Hills, which make up approximately 80% of Brown County, cover about 20,000 square miles of the state. This study reports a total of 726 plant species, subspecies, and varieties for Brown County, representing 105 families and 358 genera. Fourteen new county records were collected. A list of the vascular flora for Brown County is given and an index of similarity is used to compare Brown County …

A Comparison Of The Clarendonian Equid Assemblages From The Mission Pit, South Dakota And Ashfall Fossil Beds, Nebraska, Nicholas A. Famoso, Darrin Pagnac

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The Mission Pit locality (SDSM V5314), near Mission, South Dakota, has produced a large collection of equid teeth obtained from the Miocene Ash Hollow (=Thin Elk) Formation. Ashfall Fossil Beds (UNSM Ap-116), near Royal, Nebraska, has yielded an extensive collection of equid cranial elements and teeth derived from the Cap Rock Member, Ash Hollow Formation. The two sites are interpreted to be Clarendonian in age [12.5 to 9.0 Ma], but may contain faunal assemblages from differing Clarendonian subages.

The two sites exhibit a notably similar composition of equid genera, including the tribes Equini (Pliohippus, Calippus, and Protohippus …

Seed Production With Insect Herbivory And Fungal Occurrence For The Rare Penstemon Haydenii, Kay L Kottas, James Stubbendieck, Erin E. Blankenship, Jay B. Fitzgerald

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

We quantified seed production and viability, floral herbivory and fungal infection on blowout penstemon (Penstemon haydenii S. Watson), an endangered species of the Nebraska Sandhills, USA, in order to determine the potential for perpetuation of this, and possibly other short-lived, rare perennials of fragmented habitats. Over three years, the number of seeds per infructescence averaged 518 (SE 29.01). Plants produced an average of 1398 seeds. Seed viability of 38% reduced reproductive potential to 531 viable seeds per plant. Plants in multiple blowout sites in two counties were assigned to one of four treatments: insecticide, fungicide, both, or neither (control). …

The Freshwater Mussels (Mollusca: Bivalvia: Unionoida) Of Nebraska, Ellet Hoke

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

This paper reports the results of the first statewide survey of the freshwater mussels of Nebraska. Survey goals were: (1) to document current distributions through collection of recent shells; (2) to document former distributions through collection of relict shells and examination of museum collections; (3) to identify changes in distribution; (4) to identify the primary natural and anthropomorphic factors impacting unionids; and (5) to develop a model to explain the documented distributions. The survey confirmed 30 unionid species and the exotic Corbicula fluminea for the state, and museum vouchers documented one additional unionid species. Analysis of museum records and an …

The Ringed Crayfish, Orconectes Neglectus Neglectus, In Nebraska With A Revision Of Its Distributional Range, Steven C. Schainost

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Collections of crayfishes in Nebraska have yielded much new information on the distribution of the ringed crayfish, Orconectes neglectus neglectus. The distributional range of this species had been described as southwestern Missouri and northwestern Arkansas with extensions into Kansas and Oklahoma. Isolated, disjunct populations in northeastern Colorado, southwestern Nebraska, and northwestern and east-central Kansas were thought to be relict populations. Between 1995 and 2009, collections of crayfishes were made throughout Nebraska using various techniques including seining, trapping, dip-netting, and handgrabbing. To date, the ringed crayfish has been found in 56 streams in eight of Nebraska’s 13 river basins. In …

A Report Of Freshwater Sponge (Porifera: Spongillidae) In Central Nebraska, Todd S. Paulsen, W. Wyatt Hoback

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Little has been reported about the occurrence of freshwater sponges in Nebraska and no publications have previously recorded from central Nebraska waters. A large colony of freshwater sponges was discovered on the steel interior walls of a sunken (3.5 meters) delivery truck in a sand/rock quarry of the Platte River Valley near Kearney, Nebraska. Samples were collected and characteristics of the sponge were examined under magnification. Morphology indicates the sponge is a member of the genus Ephydatia. Although the species was not conclusively determined, it shares the most characteristics with E. muelleri. This is the first confirmed record of …

Transactions Of The Nebraska Academy Of Sciences : Volume 32 November 2011 : Editorial Contents

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

DIVISIONS OF THE NEBRASKA ACADEMY OF SCIENCES

AFFILIATED SOCIETIES OF THE NEBRASKA ACADEMY OF SCIENCES

NAS – NEBRASKA ACADEMY OF SCIENCES, INC. -- Membership, history, objectives

NATS – NEBRASKA ASSOCIATION OF TEACHERS OF SCIENCE -- Purpose & membership

EXECUTIVE COMMITTEE, 2011-2012

POLICY COMMITTEE, 2011-2012

FRIEND OF SCIENCE AWARD

2011 DONORS OF $100 OR MORE

EDITORIAL BOARD

STATE BOARD OF EDUCATION (Updated August, 2011)

EDITOR’S CORNER (Bruce Chase)

Table of Contents