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Full-Text Articles in Life Sciences

Community Structure And Secondary Production Of Aquatic Macroinvertebrates In Coastal Wetland Ponds Of The West Copper River Delta, Alaska, Following Tectonic Uplift, Ryan Glen Van Duzor Jan 2011

Community Structure And Secondary Production Of Aquatic Macroinvertebrates In Coastal Wetland Ponds Of The West Copper River Delta, Alaska, Following Tectonic Uplift, Ryan Glen Van Duzor

Master's Theses

The Great Alaska Earthquake of 1964 (magnitude 9.2) greatly altered the coastal landscape in southcentral Alaska and had particularly dramatic effects on the Copper River Delta (CRD), an ecologically and economically important area within the Chugach National Forest. The earthquake caused tectonic uplift (up to 3.5m) of the CRD coastal tidal marsh and transformed it into a perched freshwater marsh. Copper River Delta ponds, which are crucial habitat to a myriad of migrating songbirds, shorebirds, and waterfowl, are of particular interest to wildlife managers in the CRD and along the Pacific coasts of North, Central and South America. This study …


Stream Restoration In A Post-Agricultural System: Indirect Effects On Density And Secondary Production Of Aquatic Insects, Lyle Stanley Dandridge Jr Jan 2011

Stream Restoration In A Post-Agricultural System: Indirect Effects On Density And Secondary Production Of Aquatic Insects, Lyle Stanley Dandridge Jr

Master's Theses

Restoration of stream habitats, with the goal of increasing biodiversity through increasing habitat heterogeneity, has been an ongoing trend in recent decades. Current investigations suggest most of those projects fail to significantly influence ecological structure and function when evaluated in light of their affect on species richness. In order to assess the <&ldquo>success of restoration on a prairie stream in northern Illinois traditional metrics such as community composition and density were examined in addition to macroinvertebrate secondary production. Restoration of Nippersink Creek, McHenry County, Illinois was completed in 2000 and this study was conducted 8 years post-restoration. Benthic samples were …


Investigation Of A Pharmaceutical Compound With Artificial Streams: Effects Of The Antihistamine Cimetidine On Stream Ecosystem Function., Paul David Hoppe Jan 2011

Investigation Of A Pharmaceutical Compound With Artificial Streams: Effects Of The Antihistamine Cimetidine On Stream Ecosystem Function., Paul David Hoppe

Master's Theses

Pharmaceutical compounds have been widely detected in surface waters but their effects on stream ecosystems are unknown. Cimetidine (Tagamet®), a widely used H2 histamine antagonist has been detected in surface waters. To measure chronic effects of cimetidine on stream invertebrates, I conducted a long-term (83d) artificial-stream experiment. A range of cimetidine concentrations (0.07 μg L-1 to 70.0 μg L-1) were added to streams supporting populations of the amphipod Gammarus fasciatus and beetle Psephenus herricki. P. herricki individual growth rates were reduced in the presence of cimetidine, but G. fasciatus individual growth rates were not different among treatments. G. fasciatus size …


Effects Of Nitrogen And Potassium Fertilizer On Willamette Spider Mite (Eotetranychus Willamettei) (Acari: Tetranychidae), Whitney Ann Geddes Jun 2010

Effects Of Nitrogen And Potassium Fertilizer On Willamette Spider Mite (Eotetranychus Willamettei) (Acari: Tetranychidae), Whitney Ann Geddes

Master's Theses

The spider mite family (Tetranychidae) is a well known pest group in agriculture. Within this family, Willamette spider mite (Eotetranychus willamettei) causes physical harm and potential damage to grapevines (Vitis vinifera) along the central and north coast of California as well as Washington and Oregon. Willamette spider mite prefers cooler climates and feeds by puncturing the plant leaf tissue; therefore removing plant nutrients in the early stages of plant growth. Amending soils with fertilizer is a common cultural practice used in commercial vineyards, but no study has documented the interaction between the effects fertilizer concentrations have on Willamette spider mite. …


Taxonomy, Biogeography And Pest Status Of Marmara Sp. In Northern Mexico And California Citrus Production, Paul Semet Jun 2010

Taxonomy, Biogeography And Pest Status Of Marmara Sp. In Northern Mexico And California Citrus Production, Paul Semet

Master's Theses

A novel lepidopteran sex pheromone lure which was thought to be species-specific to the citrus pest Marmara gulosa (Lepidoptera: Gracillariidae) Guillén (McElfresh et al. 2009) has attracted male moths exhibiting two distinct morphologies. The morphological features examined were the sclerotized parts that make up the male genitalia; which include the valvular lobes, costal lobes, cucullar lobes, and the aedeagus. The sclerotized parts were methodically dissected and mounted on microscope slides. Digital images captured of the slide-mounted specimens proved to be inconsistent with the illustrations provided in the original Marmara gulosa species description (Guillén et al. 2001).

The morphologies of all …


The Presence Of Micropterus Salmoides (Largemouth Bass) Influences The Populations Of Rana Draytonii (California Red-Legged Frog) And Pseudacris Regilla (Pacific Treefrog) In Two Ponds In Santa Barbara County, California, Kenneth Lee Gilliland Feb 2010

The Presence Of Micropterus Salmoides (Largemouth Bass) Influences The Populations Of Rana Draytonii (California Red-Legged Frog) And Pseudacris Regilla (Pacific Treefrog) In Two Ponds In Santa Barbara County, California, Kenneth Lee Gilliland

Master's Theses

Alien fish have been implicated in the decline of Rana draytonii (California red-legged frog) and Pseudacris regilla (Pacific treefrog) populations. Micropterus salmoides (largemouth bass) is a common sport fish that has been introduced into the sympatric range of these two anuran species; however, no studies have investigated the individual influence that this alien fish has on these two species. I conducted M. salmoides control or eradication experiments during a four year study in two ponds within the Transverse Mountain Range of Santa Barbara County, California. Changes in the densities of all life stages of R. draytonii and P. regilla were …


Fish Assemblage Structure In Natural, Channelized, And Restored Sections Of Nippersink Creek, Mchenry County, Illinois, Sarah Ann Zack Jan 2010

Fish Assemblage Structure In Natural, Channelized, And Restored Sections Of Nippersink Creek, Mchenry County, Illinois, Sarah Ann Zack

Master's Theses

Degradation of aquatic habitats and loss of biodiversity are growing concerns of natural resource managers and the general public. Channelization, the common historical practice of straightening streams and rivers for agricultural interests, has had profound detrimental effects on the biodiversity of lotic fish assemblages. Nippersink Creek, McHenry County, IL is a twenty-three mile stream that flows through an area valued for its fish, wildlife, and invertebrate biodiversity. Although a portion of the stream was channelized in the 1950's, restoration efforts by the McHenry County Conservation District have recently restored historical meanders. Nevertheless, efforts to restore streams and rivers to their …


Temporal Variability Of Bioassessment Indices Used To Evaluate Three Midwestern Streams, Nia M. Haller Jan 2010

Temporal Variability Of Bioassessment Indices Used To Evaluate Three Midwestern Streams, Nia M. Haller

Master's Theses

Population, community and functional measures or metrics in rapid bioassessment programs aid in establishing biological criteria for streams and rivers. Each metric measures different aspects of community structure and is important in detecting changes in macroinvertebrate community structure that are influenced by changes in water quality. In this study, temporal variation of nine commonly used bioassessment indices was examined in three midwestern streams. The indices were calculated for each of nine replicate benthic macroinvertebrate samples collected monthly for one year from Cowpie Creek (CC), Nippersink Creek (NC) and Lawrence Creek (LC), McHenry County, Illinois. In practice, the habitat sampled for …


Diet Overlap And Competition Among Native And Non-Native Small-Bodied Fishes In The Colorado River, Grand Canyon, Arizona, Sarah Ellen Zahn Seegert Jan 2010

Diet Overlap And Competition Among Native And Non-Native Small-Bodied Fishes In The Colorado River, Grand Canyon, Arizona, Sarah Ellen Zahn Seegert

Master's Theses

Introductions of non-native fishes are threatening native fish communities in streams and rivers across the United States. The Colorado River especially has experienced numerous species invasions, and native fish populations throughout the basin are in decline. The native fish community in the Grand Canyon has been particularly affected, with half of the native fishes extirpated from the canyon. Many scientists blame interactions with non-native fishes for these declines. However, to date no one has conducted a thorough diet analysis of small-bodied fishes in the system to assess overlap between native and non-native fish diets. I analyzed the diets of native …


Resource Composition And Macroinvertebrate Resource Consumption In The Colorado River Below Glen Canyon Dam, Holly Ann Alfreda Wellard Kelly Jan 2010

Resource Composition And Macroinvertebrate Resource Consumption In The Colorado River Below Glen Canyon Dam, Holly Ann Alfreda Wellard Kelly

Master's Theses

Physical and biological changes to rivers induced by large dams can significantly alter downstream communities, decreasing the biotic integrity of these rivers. For example, completion of Glen Canyon Dam on the Colorado River in 1963 has altered the downstream ecosystem and contributed to the decline of native fish populations and dramatic changes in the macroinvertebrate communities. Physical changes associated with the dam may also influence the food resources supporting macroinvertebrate production, but this has not been previously measured. For example, autochthonous production is high in the clear tailwaters of the dam, but downstream tributary allochthonous carbon inputs are substantial and …


Arroyo Toad (Anaxyrus Californicus) Life History, Population Status, Population Threats, And Habitat Assessment Of Conditions At Fort Hunter Liggett, Monterey County, California, Jacquelyn Petrasich Hancock Dec 2009

Arroyo Toad (Anaxyrus Californicus) Life History, Population Status, Population Threats, And Habitat Assessment Of Conditions At Fort Hunter Liggett, Monterey County, California, Jacquelyn Petrasich Hancock

Master's Theses

The arroyo toad (Anaxyrus californicus) is a federally endangered species found on Fort Hunter Liggett, Monterey County, California. The species was discovered in 1996 and was determined to occupy 26.7 km of the San Antonio River from approximately 2.4 km northwest of the San Antonio Mission de Padua, to the river delta above the San Antonio Reservoir. The construction of the San Antonio Reservoir dam in 1963 isolated this northern population of arroyo toads. Through time, the Fort Hunter Liggett landscape has changed drastically. The land was heavily grazed by cattle until 1991, which considerably reduced vegetation in riparian areas. …


Restoration Of A. Fasciculatum At Rocky Canyon Granite Quarry, San Luis Obispo, Ca, Catherine L. Roy Sep 2009

Restoration Of A. Fasciculatum At Rocky Canyon Granite Quarry, San Luis Obispo, Ca, Catherine L. Roy

Master's Theses

The objective of this study was to assess the above-ground factors affecting the establishment and recovery of the dominant chaparral shrub Adenostoma fasciculatum (chamise) on the Rocky Canyon granite mine.

Attempts to restore the California chaparral have been challenging and few successful efforts have been documented. However, the California chaparral can fully recover from fire in as little as 10-15 years. Factors affecting chamise seedling establishment were tested by planting chamise seed in forty eight 1square meter plots managed to test the effects of interspecific competition with native postfire vegetation, post-mining volunteer vegetation, and intraspecific only competition. Plots were managed …


Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas Jun 2009

Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas

Master's Theses

This study examined the diet composition of ninety-nine Sacramento pikeminnow (150-410 mm [5.9-16 in] fork length [FL]) collected from the upper and lower main stem of Chorro Creek, Morro Bay Watershed, California in 2006. The goal of this study was to characterize the spatial and seasonal variability in the diet of Sacramento pikeminnow within Chorro Creek and to determine what proportion of the diet is represented by rainbow trout (Oncorhynchus mykiss) and their anadromous form (steelhead). Prey was identified in 88% of the samples collected in the early season and 84% of the samples collected in the late season. Fish …


The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind Jun 2009

The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind

Master's Theses

To gain a better understanding of the role of steroid hormones in vertebrate reproduction, we quantified steroid hormone concentrations in a free ranging population of the Northern Pacific rattlesnake, Crotalus oreganus. Plasma steroid hormone concentrations were quantified for both male and female snakes throughout the active season (Mar-Oct). We measured testosterone (T), 5α-dihydrotestosterone (DHT), and corticosterone (B) concentrations in male and female snakes. 17β-estradiol (E2) and progesterone (P) were measured in females only. We also observed breeding behaviors (e.g. consortship, courtship, and copulation) in the field and measured testis and follicle size in male and female snakes from museum collections. …


Soil Nutrient Changes Following A Typha X Glauca Invasion In A Great Lakes Coastal Wetland, Lane Marie Vail Jan 2009

Soil Nutrient Changes Following A Typha X Glauca Invasion In A Great Lakes Coastal Wetland, Lane Marie Vail

Master's Theses

Invasive species are one of the major threats to the integrity and health of Great Lakes coastal wetlands. Plant invaders, such as the hybrid cattail Typha x glauca, threaten wetlands, as they can cause shifts in ecosystem structure and function and modify biogeochemical cycles and nutrient availability. Cheboygan Marsh on the coast of Lake Huron is currently undergoing invasion by T. x glauca, and soils in T. x glauca-dominated areas of the marsh have greater soil carbon and nitrogen concentrations than in areas dominated by native vegetation. This study investigated whether T. x glauca is affecting the accumulation of carbon …


The Effects Of Crayfish Grazing On Benthic Algal Community Dynamics In Southwestern Lake Michigan, Kristi A. Zenchak Jan 1993

The Effects Of Crayfish Grazing On Benthic Algal Community Dynamics In Southwestern Lake Michigan, Kristi A. Zenchak

Master's Theses

No abstract provided.


A Study Of The Variations In The Growth Of Blue Grama Grass From Seed Produced In Various Sections Of The Great Plains Region, Andrew Riegel Aug 1939

A Study Of The Variations In The Growth Of Blue Grama Grass From Seed Produced In Various Sections Of The Great Plains Region, Andrew Riegel

Master's Theses

During the past 7 years the Great Plains Region, with its "dust bowl", has been the scene of unparalleled activity in the fields of range management and erosion control. The people of this short grass area are extremely conscious of the need for a sound, practical program of conservation that will revegetate the wasted pasture and cultivated land, which will aid materially in preserving the eroding soil. Many problems have arisen as the program of conserving the soil and the vegetation has progressed.


A History Of The Changes In Population Of Certain Mammals In Western Kansas, Floyd L. Carter Jul 1939

A History Of The Changes In Population Of Certain Mammals In Western Kansas, Floyd L. Carter

Master's Theses

This particular study has been restricted to certain mammals in western Kansas, including some on which there is little information, and others which observers would be most likely to notice in everyday life. For several years the writer has been vitally interested in the animal life in Kansas. Therefore, when the need for a study of western Kansas mammals was presented to him in the summer of 1936, the problem of this study was selected. It is hoped that this report will suggest to ecologists, historians, and others, further studies, including reasons for the changes here-in shown. What have been …


A Study Of The Structure Of Hair As A Means Of Mammal Identification., Earl R. Oyer Feb 1939

A Study Of The Structure Of Hair As A Means Of Mammal Identification., Earl R. Oyer

Master's Theses

The hair of small and medium sized mammals is often found in the stomachs, feces and pellets of predators , for example in the stomachs and feces of coyotes and in the pellets regurgitated by hawks and owls. These pellets produced by hawks and owls and the feces of mammalian predators are the undigested residue of what these animals have eaten. If the hair from these sources can be identified, then much desirable information concerning the food of predators can be obtained. The purpose of this study has been to determine whether or not such identification is possible.


Studies In Breaking The Rest Period Of Grass Plants By Treatments With Potassium Thiocyante And In Stimulating Growth With Artificial Light, Harold R. Shepherd May 1938

Studies In Breaking The Rest Period Of Grass Plants By Treatments With Potassium Thiocyante And In Stimulating Growth With Artificial Light, Harold R. Shepherd

Master's Theses

There has developed a need for a practical means of artificially breaking the rest period and of stimulating the growth of grasses so that sods can be procured early in the fall before freezing weather, brought into the greenhouse, and forced early to make an abundant vegetative growth. This need suggested the study of which this paper is the report, namely to discover whether or not the rest period of native grasses can be broken by treatment with potassium thiocyanate and their growth stimulated by artificial light supplemental to winter daylight.


The Flora Of The Tasco Lake Region, Sheridan County, Kansas, Raymond W. Darland May 1936

The Flora Of The Tasco Lake Region, Sheridan County, Kansas, Raymond W. Darland

Master's Theses

It has been customary in writing theses dealing with taxonomic problems to collect data from an entire county. Having had occasion to collect botanical specimens from the Tasco Lake for work in biology at the Sheridan High School, the wealth of plant life to be found here became apparent. The area ranges from xerophytic forms on the uplands to the hydrophytic forms in the lake and marshes. Many of the latter have never been reported from Western Kansas. Collections in preserving fluid were made of the water forms found and specimens of the landforms were mounted on regulation-sized sheets properly …


Notes On The Distribution Of Amphibia And Reptilia Of Ellis County, Kansas, L. A. Brennen May 1935

Notes On The Distribution Of Amphibia And Reptilia Of Ellis County, Kansas, L. A. Brennen

Master's Theses

Comparatively little has been done concerning the listing or recording of the Amphibia and Reptilia of Ellis County, Kansas. What records there are of the species are for the most part unpublished. Early papers dealing with Kansas herpetology are few in number. Little has been done in Ellis and the surrounding counties, so there seems to be a need for such an ecological study as has been carried out in this paper “Notes on the Distribution of Amphibia and Reptilia of Ellis County, Kansas . " The objectives kept in mind in preparing this report have been to attempt to …


An Analysis Of The Habitat Distribution Of The Fauna Of A Stream- Bank Association In Western Kansas, Olive Falls Sep 1933

An Analysis Of The Habitat Distribution Of The Fauna Of A Stream- Bank Association In Western Kansas, Olive Falls

Master's Theses

This present paper is chiefly concerned with the distribution of animals. The environmental and faunal conditions of Western Kansas have not been studied, and they are rapidly changing, due to human occupancy of the region. Therefore, a major object of this report is to put on record information in regard to the present vertebrate animal life in Western Kansas. Profound changes in the native conditions have already been recognized; for example, many animals have become extinct, and others are gradually vanishing. It is in the hope of contributing something of the facts of the status of the species in this …