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Plant Conservation In The Juan Fernandez Archipelago, Chile, Tod F. Stuessy, Ulf Swenson, Daniel J. Crawford, Gregory Anderson, Mario Silva O. Jan 1998

Plant Conservation In The Juan Fernandez Archipelago, Chile, Tod F. Stuessy, Ulf Swenson, Daniel J. Crawford, Gregory Anderson, Mario Silva O.

Aliso: A Journal of Systematic and Floristic Botany

Oceanic archipelagos often hold very specialized floras with high degrees of endemism. These floras are frequently highly vulnerable to disturbance by natural causes and human intervention. The Juan Fernandez Islands (Chile) in the Pacific Ocean are a small archipelago of only three islands. Since discovery in 1574 by Juan Fernandez, human activities have altered floristic composition and survival circumstances of the endemic species. In this paper we document past and present means of disturbance, both anthropogenic and natural, which have influenced the native vegetation. The most destructive past activities have been logging and .introduction of animals and plants, both deliberately …


Mammals Of Iowa: Holocene To The End Of The 20th Century, John B. Bowles, Daryl L. Howell, Richard P. Lampe, Howard P. Whidden Jan 1998

Mammals Of Iowa: Holocene To The End Of The 20th Century, John B. Bowles, Daryl L. Howell, Richard P. Lampe, Howard P. Whidden

Journal of the Iowa Academy of Science: JIAS

This review of Iowa's mammal fauna at the close of the 20th century summarizes changes in distributional patterns following Euroamerican settlement in the early 1800s. Data from historical records, museum specimens, and presettlement late Holocene fossils indicate presence of 69 resident mammals at that time. Hunting pressures and the conversion of prairie and forest to agricultural fields reduced the populations and ranges of many state mammals, and 14 species were extirpated by 1900. An additional 15 species are either uncommon or rare today, and the Iowa Department of Natural Resources lists four species as endangered, three as threatened and one …


Adding Nutrients To Enhance The Growth Of Endangered Sockeye Salmon: Trophic Transfer In An Oligotrophic Lake, Phaedra E. Budy, Chris Luecke, Wayne A. Wurtsbaugh Jan 1998

Adding Nutrients To Enhance The Growth Of Endangered Sockeye Salmon: Trophic Transfer In An Oligotrophic Lake, Phaedra E. Budy, Chris Luecke, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Snake River sockeye salmon Oncorhynchus nerka, listed under U.S. law as endangered in 1991 in response to a decline in anadromous adult numbers, spend their first 1–2 years in Redfish Lake, Idaho, before migrating to the sea. To determine how nutrient enhancement might influence phytoplankton, zooplankton, and fish production, we performed fertilization experiments in large enclosures in this oligotrophic lake using juvenile kokanee (lacustrine O. nerka) as analogues for endangered sockeye salmon. Fertilization of the metalimnion substantially increased chlorophyll a (150%), phytoplankton biovolume (75%), primary productivity (250%), and zooplankton biomass (200%), and moderately increased fish growth (12%) over our control …


Root-Length Densities Of Lentil And Wheat And Measuring Infiltration In The Soil In Differentsoil Tillage, Lentil-Wheat Versa Fallow-Wheat Rotation Systems Undercentral Anatolian Conditions, Didar Eser, M. Sait Adak, Andreas Biesantz Jan 1998

Root-Length Densities Of Lentil And Wheat And Measuring Infiltration In The Soil In Differentsoil Tillage, Lentil-Wheat Versa Fallow-Wheat Rotation Systems Undercentral Anatolian Conditions, Didar Eser, M. Sait Adak, Andreas Biesantz

Turkish Journal of Agriculture and Forestry

The research was carried out for four years in the two locations Haymana-Ankara and Gözlü-Konya under different climate characteristics of the Central Anatolian Region. The aim of the reseach was to improve soil fertility in dry farming areas and to increase the benefit from fallow areas. Different soil tillage treatments and lentil-wheat versa fallow- wheat rotations systems resp. were examined in these experiments. According to experimental results highest root-length densities (RLD s ) of winter sown lentils were obtained in soil layers of 0-20 and 20-40 cm in comparison to deeper soil layers of 20 cm each down to 1 …


The Role Of Bowfin, Amia Calva, In Multiple Species Management Plans, Benjamin Jacob Hausmann Jan 1998

The Role Of Bowfin, Amia Calva, In Multiple Species Management Plans, Benjamin Jacob Hausmann

Masters Theses

The major challenge to fisheries managers of the 21st century will be to maintain the diversity, not only of fishing opportunity, but also of traditionally non-game and economically unimportant species. With the relatively recent understanding of the importance of ecosystem level management, attention is being focused on native species that were often ignored or eradicated under past management practices. One such fish that has been largely ignored is the bowfin, Amia calva. Ecological data pertaining to bowfin natural history are limited and to date no attempt has been made to integrate bowfin into fisheries management decisions within the species native …


An Autecological Study On Iris Pseudacorus L. (Iridaceae), Ali Engi̇n, Nezahat Kandemi̇r, Gülcan Şenel, Mustafa Özkan Jan 1998

An Autecological Study On Iris Pseudacorus L. (Iridaceae), Ali Engi̇n, Nezahat Kandemi̇r, Gülcan Şenel, Mustafa Özkan

Turkish Journal of Botany

The ecological properties of Iris pseudacorus L., a marsh plant species, were investigated. The analysis of N%, P% and K% in the below-ground and above-ground parts of the plant was carried out. In addition, soil samples were collected and their physical and chemical aspects were analyzed.


Biological Control: An Important Component In Integrated Management Of Musca Domestica (Diptera: Muscidae) In Caged-Layer Poultry Houses In Buenos Aires, Argentina, Diana C. Crespo, Roberto E. Lecuona, Jerome A. Hogsette Jan 1998

Biological Control: An Important Component In Integrated Management Of Musca Domestica (Diptera: Muscidae) In Caged-Layer Poultry Houses In Buenos Aires, Argentina, Diana C. Crespo, Roberto E. Lecuona, Jerome A. Hogsette

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

An Integrated Management program to control Musca domestica L. was developed by evaluating cultural + chemical control, cultural + biological control + granular bait (IMP 1), and cultural + chemical + biological control + granular bait (IMP 2) in poultry houses in Argentina. Adult fly density was estimated by a modified Scudder-grid method. Percentage of house fly parasitism was estimated by direct and indirect methods. Spalangia endius Walker and Muscidifurax raptor Girault & Sanders were released at a rate of 10 parasitoids/hen/week. Complete absence of control practices allowed a sustained growth of the fly population. When larvicides and adulticides were …


Habitat Selection, Reproductive Success, And Impaling Patterns Of A Migratory Population Of Loggerhead Shrikes, Jeffrey D. Esely Jr. Jan 1998

Habitat Selection, Reproductive Success, And Impaling Patterns Of A Migratory Population Of Loggerhead Shrikes, Jeffrey D. Esely Jr.

Masters Theses

I studied habitat selection and reproductive success of a migratory population of Loggerhead Shrikes (Lanius ludovicianus migrans) as well as the temporal and spatial patterns of impaling exhibited by this population during the nesting season. The selection of breeding habitat was investigated at different spatial scales. Thirty-eight (67%) of 57 nests were located in osage orange (Maclura pomifera) trees. Shrike territories (area ≤ 200 m from nest site) contained significantly more pasture, fenceline, and perch sites, but less com, alfalfa, and forest than random sites. At larger spatial scales, more grassland was detected within 300 m …


Heartworm And Lungworms In Illinois' Canids And Their Possible Effect On Coyote Condition And Reproduction, David G. Gregory Jan 1998

Heartworm And Lungworms In Illinois' Canids And Their Possible Effect On Coyote Condition And Reproduction, David G. Gregory

Masters Theses

This study focuses on the prevalence of heartworm and lungworms in Illinois' canid species, and the effect that they may have on condition (body weight, kidney fat, marrow fat) and reproduction (placental scars) on coyote populations. A total of 1,150 coyotes (Canis latrans), 2,269 domestic dogs, 47 red foxes (Vulpes vulpes), and 2 gray foxes (Urocyon cinereoargenteus) were examined. Prevalence of heartworms (Dirofilaria immitis) averaged 17.8% in coyotes, 3.0% in domestic dogs, 2.0% in red foxes, and 0% in gray foxes. Domestic dogs not receiving any type of prophylactic treatment had a higher prevalence (12.5%) of heartworms than dogs on …


The Birds And Habitat Of Kings Park, Bradley W. Cox Jan 1998

The Birds And Habitat Of Kings Park, Bradley W. Cox

Theses : Honours

Kings Park is a large urban park in the centre of Perth with extensive areas of semi-natural bushland. The park is an important refuge for birds in the metropolitan area but is losing species through habitat disturbance. Understanding the way in which birds are related to their habitat helps to understand the effect of habitat disturbance on the bird community. The aim of this project was to generate guidelines which will aid in the management and conservation of birds in the park, through an understanding of the relationship of the birds to their habitat. The avifauna and various habitat factors …


An Ecology Problem Book, Marc Mangel, Paul Switzer, Sarah M. Eppley Jan 1998

An Ecology Problem Book, Marc Mangel, Paul Switzer, Sarah M. Eppley

Biology Faculty Publications and Presentations

This problem book has many objectives:

  • To get you to think about the course each night: do not wait until the last minute to begin working on the problems.
  • To get you to deal with data. Statistics courses that you take in the future will be more meaningful once you understand the kinds of data that arise in ecological studies.
  • To get you to be more comfortable with theoretical and quantitative methods. Not every ecologist uses those methods, but one should not be put off by them.
  • To familiarize you with material as it appears in the professional literature.


Ecology Of The Eastern Cottonmouth (Agkistrodon P. Piscivorus) At Back Bay National Wildlife Refuge: A Comparative Study Of Natural And Anthropogenic Marsh Habitats, Chad Lee Cross Jan 1998

Ecology Of The Eastern Cottonmouth (Agkistrodon P. Piscivorus) At Back Bay National Wildlife Refuge: A Comparative Study Of Natural And Anthropogenic Marsh Habitats, Chad Lee Cross

Biological Sciences Theses & Dissertations

Mark-recapture sampling and radiotelemetry were used to investigate populations of the eastern cottonmouth, Agkistrodon p. piscivorus, in both natural and anthropogenic marsh habitats at Back Bay National Wildlife Refuge (BBNWR), Virginia Beach, Virginia from autumn 1995 to late spring 1998. Mark-recapture subjects were captured, marked by ventral scale-clipping, and released back into the population. A modified Schnabel Census estimator was used to estimate population sizes and corresponding densities in both marsh systems based on a total of 244 captures of 222 individuals. Most snakes were found >0.05 in from water, but it was apparent that proximity to water played …


Management Of The Houtman Abrolhos System, Abrolhos Islands Management Advisory Council, Fisheries Department Of Western Australia Dec 1997

Management Of The Houtman Abrolhos System, Abrolhos Islands Management Advisory Council, Fisheries Department Of Western Australia

Fisheries Management Papers

In November 1995 Cabinet resolved that the Minister for Fisheries would establish the Abrolhos Islands Management Advisory Committee (AIMAC) pursuant to Section 42 of the Fish Resources Management Act 1994. The role of AIMAC is to advise the Minister for Fisheries about the management of the Abrolhos Islands and the adjoining State Territorial Waters, as detailed in Section 2.2.3.1 of this report. The AIMAC has overseen the preparation of this report on behalf of the Minister for Fisheries. This draft report contains a brief description of the Abrolhos System and its special values. It also states goals and objectives for …


The Mayfly Newsletter, Peter M. Grant Dec 1997

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Abalone Aquaculture In Western Australia. Discussion Paper And Draft Policy Guidelines., Cameron Westaway, Jeff Norriss Oct 1997

Abalone Aquaculture In Western Australia. Discussion Paper And Draft Policy Guidelines., Cameron Westaway, Jeff Norriss

Fisheries Management Papers

The purposes of this discussion paper is to highlight relevant issues associated with abalone aquaculture development and outline a set of draft policy guidelines. The paper is being disseminated to members of the aquaculture industry, commercial and recreational fishing bodies and the broader community to allow comment.


Use Of Rubidium To Label Lysiphlebus Testaceipes (Hymenoptera: Braconidae), A Parasitoid Of Greenbugs (Homoptera: Aphididae), For Dispersal Studies, Odair A. Fernandes, Robert J. Wright, Karl H. Baumgarten, Z. B. Mayo Oct 1997

Use Of Rubidium To Label Lysiphlebus Testaceipes (Hymenoptera: Braconidae), A Parasitoid Of Greenbugs (Homoptera: Aphididae), For Dispersal Studies, Odair A. Fernandes, Robert J. Wright, Karl H. Baumgarten, Z. B. Mayo

Department of Entomology: Faculty Publications

A reliable method of labeling is needed to study dispersal of the braconid parasitoid, Lysiphlebus testaceipes (Cresson), an important biological control of greenbugs, Schizaphis graminum (Rondani), on grain sorghum, Sorghum bicolor (L.) Moench. The feasibility of using aqueous solutions of rubidium chloride (RbCl) applied as a foliar spray or soil drench to label greenbugs and L. testaceipes developing within greenbugs was studied. Laboratory and field studies were conducted to identify the minimal concentration of RbCl to assure labeling of greenbugs and wasps, persistence of Rb throughout the wasp's life span, mobility of Rb to unsprayed sorghum leaves, and feasibility of …


Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley Oct 1997

Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley

Faculty and Staff Publications – Milner Library

Conservation biology is a multidisciplinary subject of recent origins. Analysis of cited monographs from the journal Conservation Biology resulted in a list of 47 monographs which were heavily cited for this discipline. Over half of these were from related disciplines such as ecology, genetics, evolution, population biology, statistics, and natural resource management.


Diet Of A Relict Population Of The Eastern Woodrat In Nebraska, Hugh H. Genoways, Patricia W. Freeman, Mary K. Clausen Sep 1997

Diet Of A Relict Population Of The Eastern Woodrat In Nebraska, Hugh H. Genoways, Patricia W. Freeman, Mary K. Clausen

University of Nebraska State Museum: Mammalogy Papers

The relict population of Neotoma floridana occurring along the Niobrara River in north-central Nebraska was found to have a diet composed of 38 types of food items of which 37 types were plants. Unique features of the summer diet of this population were a higher than expected use of red cedar (Juniperus virginiana) and invertebrates as food items.


Ecological Relationships Between The Marsh Rice Rat (Oryzomys Palustris) And The Meadow Vole (Microtus Pennsylvanicus) In Two Virginia Tidal Marshes, Christopher P. Bloch Jul 1997

Ecological Relationships Between The Marsh Rice Rat (Oryzomys Palustris) And The Meadow Vole (Microtus Pennsylvanicus) In Two Virginia Tidal Marshes, Christopher P. Bloch

Biological Sciences Theses & Dissertations

Small mammals were trapped for 23 months on two live trap grids in tidal marshes in Northampton County, on the Eastern Shore of Virginia, to examine ecological relationships between the marsh rice rat (Oryzomys palustris) and the meadow vole (Microtus pennsylvanicus). Population density, survival rates, capture probability, recruitment, residence time, and home range size were calculated for each species. Patterns of reproductive activity and fluctuations in mean weight were also observed.

There were considerable differences in population dynamics between the two sites. At Grid 2, where vegetative cover was more abundant, population densities of rice rats and meadow voles …


The Mayfly Newsletter, Peter M. Grant Jun 1997

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Flea News 54 (June 1997), Robert E. Lewis Jun 1997

Flea News 54 (June 1997), Robert E. Lewis

Flea News

Miscellanea

Advisory Committee on Immunization Practices (ACIP) update

Nomenclatural tidbits

Siphonaptera literature


The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea May 1997

The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea

Dissertations and Theses

To protect and manage Pacific Northwest salmonid stocks, sound management programs must be developed that incorporate knowledge of the ecological processes critical to their survival. One such process is the nutrient dynamic in headwater spawning streams. It is essential that we understand the trophic relationships among the spawners, the I to 3 year-old juveniles, the invertebrates, and the primary producers in these streams.

The hypothesis that I tested is that photoautotrophic production increases due to the decomposition of salmon carcasses. Increased primary production would stimulate the production of invertebrates which are an important food resource of juvenile salmonid species. The …


The Role Of Alfalfa Weevil Larvae As Prey In Adult Maintenance And Reproduction By Two Ladybird Beetle Species, Douglas R. Richards May 1997

The Role Of Alfalfa Weevil Larvae As Prey In Adult Maintenance And Reproduction By Two Ladybird Beetle Species, Douglas R. Richards

Biology

Ladybird beetles (Coccinella spp.) are important predators of pea aphids (Acyrthosiphon pisum) in alfalfa. Adult ladybird beetles also consume alternative foods such as alfalfa weevil larvae (Hypera postica) and nectar. I compared egg production and ovariole condition of Coccinella septempunctata (an Old World species introduced to North America) and Coccinella transversoguttata (an indigenous North American species) that were maintained on diets of pea aphids, alfalfa weevil larvae, sugar water ("artificial nectar"), or various combinations of these foods. In the first experiment, gravid females of both species continued to lay many eggs and had large ovarioles …


Evaluation Of Translocation Criteria For Trumpeter Swans Reintroduced To Northern Utah: Habitat Quality And Interactions With Tundra Swans, Katharina A. M. Engelhardt May 1997

Evaluation Of Translocation Criteria For Trumpeter Swans Reintroduced To Northern Utah: Habitat Quality And Interactions With Tundra Swans, Katharina A. M. Engelhardt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fifty-seven Trumpeter swans (Cygnus buccinator) were translocated to the Bear River Migratory Bird Refuge and the Bear River Club Company in northern Utah. The purpose of this effort was to encourage dispersal of the Rocky Mountain population of Trumpeter swans during the winter, and to reestablish a migratory route to southern wintering grounds. I assessed the success of the translocation by evaluating 13 translocation criteria proposed in the literature. In this study I addressed two of these criteria in detail by evaluating habitat quality at the translocation sites and by analyzing potential competitive interactions with Tundra swans ( …


The Role Of Cold Acclimatization On The Biogeography Of The Mountain Chickadee (Parus Gambeli) And The Juniper Titmouse (Parus Ridgwayi), Sheldon J. Cooper May 1997

The Role Of Cold Acclimatization On The Biogeography Of The Mountain Chickadee (Parus Gambeli) And The Juniper Titmouse (Parus Ridgwayi), Sheldon J. Cooper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biogeographic patterns of animals are shaped by biotic interactions, such as competition, and by abiotic factors, such as climate. Mountain Chickadees (Parus gambeli) and Juniper Titmice (Parus ridgway) are permanent residents of regions of western North America and are ecologically similar, but have different northern range limits. l measured several physiological variables, including basal metabolic rate (BMR), peak metabolic rate (PMR = maximal thermogenic capacity), metabolic response to varying environmental temperature (MRT), evaporative water loss (EWL), and daily energy expenditure (DEE) for summer-and winter-acclimatized Mountain Chickadees and Juniper Titmice to determine if seasonal and interspecific variation in cold tolerance and …


Social Organization Of Neotoma Micropus, The Southern Plains Woodrat, Sarah A. Conditt, David O. Ribble Apr 1997

Social Organization Of Neotoma Micropus, The Southern Plains Woodrat, Sarah A. Conditt, David O. Ribble

Biology Faculty Research

This study described the social organization of Neotoma micropus, the southern plains woodrat, using radiotelemetry. We studied woodrats from September 1994 through April 1995 at the Urban Wilderness Reserve in S Bexar County, Texas. Sixteen individuals (three adult males, 11 adult females, and two subadult males) were radiocollared and located in the evening or early morning during January and February. Seventy-four percent of female radiolocations and 57% of male radiolocations were from their respective nests. No more than one adult individual was observed at any nest at the same time. Males had significantly larger (x = 1899 m2 …


Isotope Ratio Studies Of Marine Mammals In Prince William Sound, Donald M. Schell, Amy Hirons Apr 1997

Isotope Ratio Studies Of Marine Mammals In Prince William Sound, Donald M. Schell, Amy Hirons

Marine & Environmental Sciences Faculty Reports

This project consists of two components: (1) provision of analytical services for the stable isotope ratio investigations associated with Exxon Valdez oil spill projects, and (2) an investigation of food web relationships and trophic interactions of harbor seals and other top consumers of Prince William Sound (PWS). Through the use of harbor seal tissues collected from native harvested animals and tagging programs, seasonal and migrational information has been obtained with regard to prey utilization and trophic status at differing locations within the sound and the adjacent Gulf of Alaska. Preliminary results indicate that within PWS, harbor seals fall at the …


Effects Of Shelterbelts On The Aerial Distribution Of Insect Pests In Muskmelon, Mary Ellen Dix, Laurie Hodges, James R. Brandle, Robert J. Wright, Mark O. Harrell Apr 1997

Effects Of Shelterbelts On The Aerial Distribution Of Insect Pests In Muskmelon, Mary Ellen Dix, Laurie Hodges, James R. Brandle, Robert J. Wright, Mark O. Harrell

Department of Entomology: Faculty Publications

Sticky traps were used to measure how tree shelterbelts influence the abundance of crop insect pests and beneficial arthropods in muskmelon (Cucumis melo L.) plots in eastern Nebraska. Abundance of striped cucumber beetles {Acalymma vittatum Fabricius (Coleoptera: Chrysomelidae)} , southern corn rootworms {Diabrotica undecimpunctata howardi Barber (Coleoptera: Chrysomelidae)}, and northern corn rootworms {D. barberi Smith & Lawrence (Coleoptera: Chrysomelidae)} was similar in exposed and sheltered plots. Western corn rootworms {D. virgifera LeConte (Coleoptera: Chrysomelidae)} were significantly more abundant in exposed plots. More lady beetles (Coleoptera: Coccinellidae) and ichneumonid wasps (Hymenoptera: Ichneumonidae) were caught on traps …


The Biological Flora Of Coastal Dunes And Wetlands. Sesuvium Portulacastrum (L.) L., Robert I. Lonard, Frank W. Judd Jan 1997

The Biological Flora Of Coastal Dunes And Wetlands. Sesuvium Portulacastrum (L.) L., Robert I. Lonard, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Sesuvium portulacastrum (L.) L. (sea purslane, cenicilla) is a pantropical, perennial, trailing herb (Aizoaceae) with pink-purple or occasionally white flowers that grows on coastal beaches of five continents and many islands. Herein we present a review of the biology of S. portulacastrum. It is an important pioneer species on sandy beaches in the subtropics and tropics, where its stoloniferous, mat-forming growth habit promotes embryonic dune formation in belts parallel to the shoreline. Colonies act as barriers to intercept and hold water and wind transported sand. Sesuvium portulacastrum's success as a colonizing species is related, in large part, to its …


Species Pools Of Seed Plants In Eastern Asia And North America, Shiyou Li, Kent T. Adair Jan 1997

Species Pools Of Seed Plants In Eastern Asia And North America, Shiyou Li, Kent T. Adair

eBooks

"In their monograph, Species Pools of seed plants in Eastern Asia and North America, Drs. Li and Adair present a comprehensive analysis of data collected during a ten-year study involving 10,000 plant species in east Asia and North America."