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The Prairie Naturalist Volume 21, No.3 September 1989 Sep 1989

The Prairie Naturalist Volume 21, No.3 September 1989

The Prairie Naturalist

SEED DISPERSAL CHARACTERISTICS OF PLAINS SILVER SAGEBRUSH ▪ C. L. Wambolt, T. Walton, and R. S. White

ON THE TRAIL OF THE ANT, VEROMESSOR LOBOGNATHUS . ▪ G. C. Wheeler and J. Wheeler

LAND USE RELATIONSHIPS TO AVIAN CHOLERA OUTBREAKS IN THE NEBRASKA RAINWATER BASIN AREA ▪ B. J. Smith, K. F. Higgins, and C. F. Gritzner

INCIDENCE OF LEAD SHOT IN THE RAINWATER BASINS OF SOUTH CENTRAL NEBRASKA ▪ . D. W. Oates

REPRODUCTION, RECRUITMENT, AND SURVIVAL OF BROWN AND RAINBOW TROUT IN A PRAIRIE COTEAU STREAM ▪ C. L. Milewski and D. W. Willis

SIZE STRUCTURE AND CATCH …


Distribution And Marketing Of Western Australia Rock Lobster., P. J. Monaghan Aug 1989

Distribution And Marketing Of Western Australia Rock Lobster., P. J. Monaghan

Fisheries Management Papers

This report describes the marketing and distribution of Western Australian rock lobster products in the major consuming countries namely, USA, Japan and Taiwan. It is based on a study which was commissioned by the Fisheries Department of Western Australia who sought, for the benefit of industry generally, an understanding of the world lobster markets.


Testing Macroevolutionary Hypotheses With Cladistic Analysis: Evidence Against Rectangular Evolution, Cliff A. Lemen, Patricia W. Freeman Jul 1989

Testing Macroevolutionary Hypotheses With Cladistic Analysis: Evidence Against Rectangular Evolution, Cliff A. Lemen, Patricia W. Freeman

School of Natural Resources: Faculty Publications

The properties of cladistic data sets from small monophyletic groups (6-1 2 species) are investigated using computer simulations of macroevolution. Two evolutionary models are simulated: gradualism and the punctuated-equilibrium hypothesis. Under the conditions of our simulations these two models of evolution make consistently different predictions about the distribution of autapomorphies among species. When strict stasis is enforced, the punctuated-equilibrium hypothesis predicts that the most expected number of autapomorphies per species will be zero, no matter how many characters are used in the analysis. As the number of characters used in the analysis increases, the distribution of the number of autapomorphies …


The Remipedia (Crustacea): A Study Of Their Reproduction And Ecology, Jill Yager Jul 1989

The Remipedia (Crustacea): A Study Of Their Reproduction And Ecology, Jill Yager

Biological Sciences Theses & Dissertations

Remipedes are an unusual group of troglobitic crustaceans that live exclusively in anchialine caves. Since their discovery in 1979, nine species have been described, seven of which are found in caves in the West Indies, one from the Yucatan peninsula of Mexico and one from the Canary Islands. Most of what is known about these animals has come mainly from taxonomic descriptions. Little has been published about their reproductive biology or ecology. The objectives of this dissertation were to investigate the reproductive biology and ecology of the remipedes inhabiting Sagittarius Cave on Grand Bahama Island, Bahamas.

Sagittarius Cave was chosen …


Picoplankton/Phytoplankton Dynamics In Hampton Roads, Virginia, Leslie E. Dorworth Jul 1989

Picoplankton/Phytoplankton Dynamics In Hampton Roads, Virginia, Leslie E. Dorworth

OES Theses and Dissertations

The biomass distribution of the three main size components of the phytoplankton (net, nano, and picoplankton) was examined in the lower Chesapeake Bay. Work was done at two stations during the spring and neap tidal cycles when freshwater flow into the bay was at its seasonal minimum and maximum. Emphasis was placed on how the picoplankton ( < 2.0 μm, > 0.2 μm) reacted during the sampling period.

Picoplankton made up approximately 13% of the total biomass, during the observed time period, at the more oceanic station. The picoplankton fraction contributed up to 16% of the total biomass at the estuarine station. From this …


Effects Of Resident Species On Recruitment Into A Community: Larval Settlement Versus Post-Settlement Mortality In The Oyster Crassostrea Virginica, Roman Zajac, Richard W. Osman, Robert B. Whitlatch Jun 1989

Effects Of Resident Species On Recruitment Into A Community: Larval Settlement Versus Post-Settlement Mortality In The Oyster Crassostrea Virginica, Roman Zajac, Richard W. Osman, Robert B. Whitlatch

Biology and Environmental Science Faculty Publications

Laboratory and field experiments revealed that a variety of species of common, sessile invertebrates, including barnacles, ascidians, and bryozoans, affected the settlement and post-settlement abundance of the oyster Crassostrea virginica (Gmelin). While the nature of the effects varied, most species both reduced oyster settlement by covering and removing substrate available for attachment, and increased settlement on adjacent surfaces. The solitary ascidians Ciona intestinalis (L.) and Styela clava (Herdman), were found to be predators of oyster larvae. Post-settlement survivorship and growth were also strongly affected by the presence of sessile species. In most cases the effects were negative and correlated with …


Southern Demersal Gillnet And Longline Fishery., Management Advisory Committee Jun 1989

Southern Demersal Gillnet And Longline Fishery., Management Advisory Committee

Fisheries Management Papers

In its report to the Ministier for Fisheries in November 1986, the Southern Western Australian Shark Working Group recommended the establishment of an Industry/Government Mangement Advisory Committee to provide managememt advice on the fishery to the Minister for Fisheries. The Advisory Committee held its first meeting in Albany on 23 February 1989. After being briefed on the state of shark stocks, the Committee's deliberations fell into three broad categories. In the first category there was sufficient time and information available to make a recommendation to the Minister for Fisheries. In the second category, discussion commenced, but was held over to …


Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle Jun 1989

Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle

Publications (WR)

Temporal and spatial patterns of age 0 threadfin shad (Dorosoma petenense) abundance and growth, in the Overton Arm of Lake Mead, were examined to evaluate the effects of resource availability on the young fish. This was part of a larger, game fishery enhancement study (Lake Mead Fertilization Project), designed to assess feasability of increasing survivorship of larval/juvenile shad by boosting phosphate levels, thereby increasing algal and zooplankton biomass, during the shad spawning period. Shad are the primary forage base for the striped bass (Morone saxatilis) and black bass (Macropterus salmoides) fisheries. Weekly samples were …


Management Of The Perth Metropolitan Purse-Seine Fishery., N. Moore May 1989

Management Of The Perth Metropolitan Purse-Seine Fishery., N. Moore

Fisheries Management Papers

This report outlines the management plan for the limited entry purse-seine fishery for small pelagic fish in coastal waters between Lancelin and Cape Bouvard and seaward to the 200 mile limit of the Australian Fishing Zone. The plan includes Cockburn Sound.


The Benefits Of Weaning Cattle In The Kimberley, David Pratchett, Stuart Young May 1989

The Benefits Of Weaning Cattle In The Kimberley, David Pratchett, Stuart Young

Animal production and livestock research reports

The Kimberley region was populated with Shorthorn cattle from Queensland and New Sonth Wales in the 1880's. The descendants of these cattle known as Kimberley Shorthorn are still the predominant breed in the region. The relatively poor performance of these cattle under the harsh Kimberley conditions and the fact that changing the genotype can improve productivity was recently published (Pratchett D. WADA Journal No. 4 1988)

While the adoption of Bos indicus breeds is the correct move, improved husbandry can also increase the productivity of the Kimberley Shorthorn cow. The majority of cattle in the Kimberley are not weaned. Sometimes …


An Analysis Of Institutional Approaches For Management Of Common Rangeland Resources In Sub-Saharan Africa, Mohale Gabriel Sekoto May 1989

An Analysis Of Institutional Approaches For Management Of Common Rangeland Resources In Sub-Saharan Africa, Mohale Gabriel Sekoto

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

The purpose of this report is to address the issues that are relevant to the management of common rangeland resources in Sub-Saharan Africa. I feel that the issues presented here are among some of those which are important and need to be considered in order to understand the kind of performance perceived about the efforts to develop the range and livestock in pastoral societies. In this report, three case studies have been reviewed, regarding institutional approaches tried to manage common rangelands. These case studies are about group ranches in Kajiado District, Kenya and in Upper Volta and the Sehlabathebe Grazing …


Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson May 1989

Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root exploitation of enriched soil microsites was examined for the tussock grasses Agropyron desertorum and Agropyron spicatum and the shrub Artemisia tridentata. Two mechanisms of exploitation of the microsites were examined: root proliferation and changes in nutrient uptake capacity. One day after nutrient solution was applied to small soil patches, the mean relative growth rate of Agropyron desertorum roots in enriched patches was two to four times greater than for roots of the same plants in soil patches treated with distilled water. This rapid and striking root proliferation occurred in response to N-P-K enrichment as well as to P or …


Using Computer Imaging To Assess Visual Impacts Of Forest Insect And Disease Pests, Daniel Rabin May 1989

Using Computer Imaging To Assess Visual Impacts Of Forest Insect And Disease Pests, Daniel Rabin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forest insect and disease pests alter the appearance of trees, thereby impacting visual resources. Because of the complexity of most forest landscapes, the degree of visual impact of pest-infested forest stands is difficult to quantify.

This paper describes a method of measuring visual impacts of pest-infested forest stands. Photographs of healthy Ponderosa pine trees were entered into a computer video-image-processing system. Using this system, images of trees were altered to simulate different degrees of infestation by limb rust, a forest pathogen.

The altered and unaltered images were shown to groups of observers who rated the scenes in terms of "scenic …


Management, Foraging Behavior, Diet Composition And Forage Quality Of Free-Ranging But Herded Camels In Ceeldheer District, Central Somalia, Ahmed A. Elmi May 1989

Management, Foraging Behavior, Diet Composition And Forage Quality Of Free-Ranging But Herded Camels In Ceeldheer District, Central Somalia, Ahmed A. Elmi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In Somalia, camel (Camelus dromedarius) survivability and milk production has been higher than for other domestic livestock and contributes substantially to the subsistence of Somali pastoralists. The objective of this research was to study management, foraging behavior and nutrition of camels in their natural habitat to determine how production continues under seasonal nutritional stress.

Management systems of Ceeldheer pastoralists are based on available natural pasture and water. The natural rotation grazing system maintained an ecological equilibrium in the District.

Pastoralists manipulate their herds to suit existing environmental conditions, family needs and labor availability for herding. In herd management, …


Fee Hunting Opportunities On Private Land In Utah: An Economic And Policy Analysis, Lucy A. Jordan May 1989

Fee Hunting Opportunities On Private Land In Utah: An Economic And Policy Analysis, Lucy A. Jordan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Objectives of this research were (1) to describe fee hunting as it is currently practiced in Utah and (2) to assess the adequacy of fee hunting efforts in addressing the problems of wildlife habitat and hunter access on private land. To collect information, Utah landowners who charged for deer (Odocoileus hemionus) or elk (Cervus elaphus) hunting in 1986 were surveyed by telephone and mail.

Compared to the average Utah livestock rancher, those involved in fee hunting have larger livestock operations and have owned their property longer. They are Utah natives. Fee hunting is concentrated in northern …


A Review Of The Shark Bay Pearling Industry., D. A. Hancock Apr 1989

A Review Of The Shark Bay Pearling Industry., D. A. Hancock

Fisheries Management Papers

While there are currently only two pearl culture leases in Shark Bay, two new applications for leases have already been received by the W.A. Fisheries Department. Increased interest is being generated about pearl culture in Shark Bay, which will need to be considered against the background of management plans designed to restrict further entry into other areas, notably the pearly industry of W.A from Exmouth Gulf northwards, and the pearling industry of the Northern Territory. Recent successes with pearl culture in both those areas, and the greatly increased revenues and high lease transfer values realised, must inevitably focus interest on …


Wolf Population Survival In An Area Of High Road Density, L. David Mech Apr 1989

Wolf Population Survival In An Area Of High Road Density, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Wolf mortality in a high-road-density area of Minnesota exceeds that in an adjacent wilderness, and is primarily human-caused. The wolf population there is maintained primarily by ingress from the adjacent wilderness areas. A road density of 0.58 km/km2 can be exceeded and the area still support wolves if it is adjacent to extensive roadless areas.


Evidence For The Role Of Ecdysteroids In The Genital Sex Pheromone Of Two Species Of Hard Ticks, Dermacentor Variabilis (Say) And Dermacentor Andersoni Stiles, Demar Taylor Apr 1989

Evidence For The Role Of Ecdysteroids In The Genital Sex Pheromone Of Two Species Of Hard Ticks, Dermacentor Variabilis (Say) And Dermacentor Andersoni Stiles, Demar Taylor

Biological Sciences Theses & Dissertations

Neutering of part-fed females virtually eliminated copulatory behavior in Dermacentor variabilis and D. andersoni males. Extracts from the anterior reproductive tracts (ART) of part-fed (7 days) females restored the male copulatory behavior in conspecific neutered females, suggesting the presence of a genital sex pheromone (GSP). Similar extracts from unfed females did not restore the behavior, suggesting that the pheromone was produced during feeding. Perception of the GSP by sensillae on the male cheliceral digits was confirmed by electrophysiological techniques.

Ecdysteroids, specifically ecdysone and 20-OH-ecdysone were shown to be present in the anterior reproductive tracts in excess of amounts that could …


Non-Breeder Asymmetry In Florida Scrub Jays, Jonathan P. Balcombe Mar 1989

Non-Breeder Asymmetry In Florida Scrub Jays, Jonathan P. Balcombe

Ethology Collection

The data of Woolfenden and Fitzpatrick (1984) show a statistically significant asymmetry in the sex ratio of non-breeders when one of the breeders is not the non-breeder's parent. 1 propose that the asymmetry is attributable to a combination of two factors acting on non-breeders: the value of inheriting a territory, and incest avoidance. Although natal territories are only occasionally inherited by non-breeders, and then apparently only by males, the rate of inheritance is significantly higher for parent/step-parent breeders (n = 6) than when both breeders are the non-breeder's parents (n = 1). An alternative hypothesis, that step-parents determine the non-breeder …


Comparison Of Marine And Terrestrial Ecological Systems, Lter Steering Committee Mar 1989

Comparison Of Marine And Terrestrial Ecological Systems, Lter Steering Committee

Long Term Ecological Research Network

Report of a workshop held in Santa Fe, New Mexico.

A century from now humanity will live in a managed -- or mismanaged -- global garden.

We are debating the need to preserve tropical forests. Farming of the sea is providing an increasing part of our fish supply. We are beginning to control atmospheric emissions. In a hundred years these separate aspects will need to be integrated into a single management system. We shall use novel farming practices and genetic engineering of bacteria to manip­ulate the methane production of rice fields world-wide. The continental shelf, especially off Asia, will be …


Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife Mar 1989

Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife

Publications (WR)

Red swamp crayfish (Procambarus clarkii) were trapped in Flamingo Wash, an urban wash of Las Vegas, during four periods of 1988. Life history and reproductive success were determined. The trapped crayfish were marked and released into a study cove in Lake Mead as part of an experimental stocking program. Retrap data from the study cove were used to determine life history, habitat preferences, and movement patterns of the stocked crayfish. In addition, a literature search was done on red swamp crayfish ecology, including food preferences, life history, habitat preferences and fish predation.


The Prairie Naturalist Volume 21, No.1 March 1989 Mar 1989

The Prairie Naturalist Volume 21, No.1 March 1989

The Prairie Naturalist

WINTER RAPTOR USE OF THE PLATTE AND NORTH PLATTE RIVER VALLEYS IN SOUTH CENTRAL NEBRASKA ▪ G. R. Lingle

CHARACTERISTICS OF RUFFED GROUSE DRUMMING SITES IN THE TURTLE MOUNTAINS, NORTH DAKOTA ▪ J. W. Schulz, E. L. Bakke, and J. F. Gulke

USE OF A TRIBUTARY BY FISHES IN A GREAT PLAINS RIVER SYSTEM ▪ J. B. Smith and W. A. Hubert

PLANT AND ANIMAL COMMUNITY RESPONSES TO RESTORED IOW A WETLANDS ▪ T. G. LaGrange and J. J. Dinsmore

COLEOPTERA SPECIES INHABITING PRAIRIE WETLANDS OF THE COTTONWOOD LAKE AREA, STUTSMAN COUNTY, NORTH DAKOTA ▪ B. A. Hanson and G. …


Fisheries Management Paper No.23 - Management Of The South-West Inshore Trawl Fishery., N. Moore Feb 1989

Fisheries Management Paper No.23 - Management Of The South-West Inshore Trawl Fishery., N. Moore

Fisheries Management Papers

This report outlines the management plan for the south west inshore trawl fishery which already operates in coastal waters less than 200 metres deep between Guilderton and Cape Leeuwin.

This management plan takes into account these important concerns and has specifically set aside a strip of coastal area from Cape Bouvard to Cape Leeuwin for recreational usage and for protection of the benthic community, and closed the management zone north of Burns Beach to trawling.


A Report On Marron Fishing In Western Australia., Doug Wenn Feb 1989

A Report On Marron Fishing In Western Australia., Doug Wenn

Fisheries Management Papers

The marroning experience is one enjoyed by many Western Australians. A rapid increase in fishing effort evidenced by the increase in number of recreational fishing licences issued, combined with low rainfall in the last few years resulted in a dramatic reduction of marron catch rates during 1986/87. In view of the state of marron stocks, the Minister for Fisheries considered it appropriate to close the 1987/88 marron season.


Investigation Of Lower Colorado River Valley Desert Soil Mineral And Nutrient Content In Relation To Plant Proximity And Identity, Jane N. Hildreth Jan 1989

Investigation Of Lower Colorado River Valley Desert Soil Mineral And Nutrient Content In Relation To Plant Proximity And Identity, Jane N. Hildreth

Theses Digitization Project

No abstract provided.


Age Assessment Of White Bass From Otoliths, Dorsal Spines And Scales, Raj V. Kilambi, Thoniot T. Prabhakaran Jan 1989

Age Assessment Of White Bass From Otoliths, Dorsal Spines And Scales, Raj V. Kilambi, Thoniot T. Prabhakaran

Journal of the Arkansas Academy of Science

Otoliths, dorsal spines, and scales of 85 white bass collected in1987 from a pre-spawning group were used forage assessment. Agreement between spine and otolith ages were 78.3%, between scale and otolith ages was 68.2%. Unlike spine ages, percent agreement of scale ages with otolith ages decreased from small to large fish. Length-frequency analysis in conjunction with ages assessed by the three calcified structures showed that dorsal spines and scales underestimated white bass ages compared to the otoliths. Clarity of the otolith annuli, even of the older fish, makes them a reliable source for white bass age assessment.


Fisheries Management Paper No. 21 - Commercial Fishing Licensing In Western Australia., Fisheries Department Of Western Australia. Jan 1989

Fisheries Management Paper No. 21 - Commercial Fishing Licensing In Western Australia., Fisheries Department Of Western Australia.

Fisheries Management Papers

The purpose of this paper is to provide those in the fishing industry, as well as those planning to enter the industry, with a statement on the policies on boat licences, boat replacements and transfers, limited and restricted entry licences and licence splitting as they apply to the fisheries managed under the Western Australian Fisheries Act. The pearling industry, which is managed under another Act, is not included.


Desert Explorations - A Videodisc Exhibit Designed For Flexibility, Judy Diamond, Alan B. Bond, Atsusi Hirumi Jan 1989

Desert Explorations - A Videodisc Exhibit Designed For Flexibility, Judy Diamond, Alan B. Bond, Atsusi Hirumi

Alan Bond Publications

Using an interactive exhibit does not provide the same experience for everyone. How visitors understand an exhibit, what associations it evokes, and even how it is physically utilized may differ widely. This article describes an exhibit that was designed to let visitors tailor their explorations to their own interests and motivation. The exhibit, called Desert Explorations, gives visitors choices of what to see and how to learn about what they see. This exhibit also is an example of a way of developing interactive videodisc exhibits that is relatively inexpensive yet may be tailored to a particular topic or hall. This …


Survey And Reconnaissance Of Sea Turtles In The Northern Gulf Of Mexico, Larry Ogren Jan 1989

Survey And Reconnaissance Of Sea Turtles In The Northern Gulf Of Mexico, Larry Ogren

United States Department of Commerce: Staff Publications

This is a report on the results of an aerial survey of nesting beaches conducted during the period from May 16, 1977 to August 11, 1977. The area covered included the barrier beaches and offshore islands from the Florida-Alabama state line to the Rio Grande, Texas. Additional historical information is provided in order to compare current nesting activity with previous years as well as anecdotal observations on the occurrence of sea turtles in this region.


From The Gulf To The Rio Grande: Human Adaptation In Central, South, And Lower Pecos Texas, Thomas Hester, Stephen L. Black, D. Gentry Steele, Ben W. Olive, Anne A. Fox, Karl Reinhard, Leland C. Bement Jan 1989

From The Gulf To The Rio Grande: Human Adaptation In Central, South, And Lower Pecos Texas, Thomas Hester, Stephen L. Black, D. Gentry Steele, Ben W. Olive, Anne A. Fox, Karl Reinhard, Leland C. Bement

Karl Reinhard Publications

The South Texas area, Region 3 of the Southwestern Division, U.S. Army Corps of Engineers, is synthesized from archeological and bioarcheological perspectives. Three distinct geographic units within Region 3 are treated in detail: Central Texas Plateau Prairie, South Texas Plains, and Lower Pecos Canyonlands. More than 11,000 years of human adaptation are chronicled for this area, stretching from the Gulf of Mexico to the Rio Grande along the border with northeastern Mexico. Particular attention is devoted to a consideration of the region's prehistoric record; significant problems and data gaps are outlined. For the first time, a compilation has been done …