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Full-Text Articles in Life Sciences

Life Histories, Diets, And Secondary Production Of Odonata Along A Temperature Gradient On The Copper River Delta, Alaska, Nicole Emilie Furlan Jan 2014

Life Histories, Diets, And Secondary Production Of Odonata Along A Temperature Gradient On The Copper River Delta, Alaska, Nicole Emilie Furlan

Master's Theses

Dragonflies (Odonata: Epiprocta) and damselflies (Odonata: Zygoptera) are a conspicuous aspect of the biota in ponds on southcentral Alaska's Copper River Delta (CRD). Odonate densities, secondary production, and diets were assessed in sixteen ponds classified by delta region (east vs. west) and landscape type (outwash plain (OP) vs uplifted marsh (UM)).

Enallagma boreale (Coenagrionidae) comprised 48.5% of collected odonates. Leucorrhinia hudsonica (Libellulidae) and Aeshna juncea (Aeshnidae) comprised 36.6% and 10.4% of collected odonates, respectively. L. hudsonica densities and secondary production were significantly higher (p<0.001) in west UM ponds than in other pond types. Ostracods (Ostracoda) and water boatmen (Corixidae) dominated west OP A. juncea diets. Midge larvae (Chironomidae) dominated A. juncea diets in remaining pond types, occurring in 68% of foreguts. 27% of A. juncea foreguts demonstrated intraguild predation, and 6% of foreguts demonstrated cannibalism. Foreguts containing threespine stickleback (Gasterosteus aculeatus) revealed A. juncea's apex predator role in CRD ponds.


The Comparative Morphology Of The Pectoral Free Rays In Scorpaenoid Fishes (Perciformes: Scorpaenoidea)), Jeremy Peter Harris Jan 2013

The Comparative Morphology Of The Pectoral Free Rays In Scorpaenoid Fishes (Perciformes: Scorpaenoidea)), Jeremy Peter Harris

Master's Theses

The pectoral fins of many benthic taxa have evolved many unique features used to interact with the substrate. In one such group, the searobins (Triglidae: Scorpaenoidea), three of the pectoral fin rays have become separated from the fin as a whole, allowing them to operate as a separate appendage from the fin as a whole. The anatomical structure of these "free rays" was investigated and several previously unreported muscle and bone variations were found. This method was extended to include members of four other scorpaenoid families which possess free rays, which revealed important differences in the muscle, bone, and nervous …


Activity Patterns And Spatial Resource Selection Of The Eastern Garter Snake (Thamnophis Sirtalis Sirtalis), Matthew Gregory Most Jan 2013

Activity Patterns And Spatial Resource Selection Of The Eastern Garter Snake (Thamnophis Sirtalis Sirtalis), Matthew Gregory Most

Master's Theses

Snake species usually exhibit seasonal variations in activity patterns, home-range size and the use of respective habitat. Using mark-recapture protocols I marked 96 individual Thamnophis sirtalis sirtalis specimens in Lake Forest, IL to determine the independent variables that best explained habitat selection in a population of Eastern Garter Snakes (T. s. sirtalis). Specifically, I focused on the relationship between seasonal movement and home range size of male and female garter snakes. I analyzed the habitat preferences and spatial ecology of Eastern Garter Snakes during the 2011 sampling season and modeled the relationship between preferred or avoided habitat, in conjunction with …


Aquatic Macroinvertebrate Response To Invasion And Subsequent Removal Of Typha × Glauca From Great Lakes Coastal Marshes, Kimberly Anne Greene Jan 2013

Aquatic Macroinvertebrate Response To Invasion And Subsequent Removal Of Typha × Glauca From Great Lakes Coastal Marshes, Kimberly Anne Greene

Master's Theses

Aquatic macroinvertebrates are important in wetland ecosystems; many fish and wildlife species depend upon them for food resources and they aid in nutrient cycling. Wetland macroinvertebrate communities are influenced by plant community composition; as such, this study examined two implications of invasive hybrid cattail, Typha × glauca (Typha), on aquatic macroinvertebrate communities in northern Great Lakes coastal wetlands: 1) how the presence of nearly monotypic stands of Typha alters wetland aquatic macroinvertebrate communities and 2) how manual removal of Typha, via mowing and manual tilling, impacts these invertebrate communities along with wetland plant communities. I found that …


The River Continuum Redux: Aquatic Insect Diets Reveal The Importance Of Autochthonous Resources In The Salmon River, Idaho, Kathryn Vallis Jan 2011

The River Continuum Redux: Aquatic Insect Diets Reveal The Importance Of Autochthonous Resources In The Salmon River, Idaho, Kathryn Vallis

Master's Theses

Along a river network, changes in the physical characteristics of a stream - changes articulated by the River Continuum Concept (RCC) - have been predicted to influence stream food webs, particularly the resources supporting aquatic macroinvertebrates. Although diets of macroinvertebrates can track resource availability along the longitudinal gradient of streams, insect diets were not assessed in the original RCC study; rather, insects were grouped into functional feeding groups (FFGs). In addition, global climate change is increasing the frequency and spatial extent of wildfire and beetle outbreaks throughout the western United States and could affect riparian vegetation and the amount of …


Cattail (Typha X Glauca) Invasion In Wetlands Of The Great Lakes Region: Are Impacts Time-Dependent?, Mark Edwin Mitchell Jan 2011

Cattail (Typha X Glauca) Invasion In Wetlands Of The Great Lakes Region: Are Impacts Time-Dependent?, Mark Edwin Mitchell

Master's Theses

Some species introduced into new regions have the potential to greatly impact native diversity and ecosystem functioning. The invasive hybrid cattail, Typha X glauca, has established in wetlands across the Great Lakes region decreasing native plant diversity and altering soil and microsite characteristics. We utilized 80 years of historical aerial photographs from the Illinois Beach State Park wetland complex to map the spread and determine the age of T. X glauca stands. Floristic, edaphic, and environmental data were collected from plots across an invasion-age gradient to determine the impacts of T. X glauca and time since invasion on environmental variables. …


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 …


Advancing Synthetic Ecology: Database System To Facilitate Complex Ecological Meta-Analyses, V. Bala Chaudhary Apr 2010

Advancing Synthetic Ecology: Database System To Facilitate Complex Ecological Meta-Analyses, V. Bala Chaudhary

School of Environmental Sustainability: Faculty Publications and Other Works

No abstract provided.


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 …


Sustainability Education As A Catalyst For University And Community Partnerships, Shane Lishawa, Adam Schubel, Alison Varty, Nancy Tuchman Jan 2010

Sustainability Education As A Catalyst For University And Community Partnerships, Shane Lishawa, Adam Schubel, Alison Varty, Nancy Tuchman

School of Environmental Sustainability: Faculty Publications and Other Works

Universities are uniquely positioned to lead society toward sustainability and their collaborations with community organizations are essential to this transition. The Biodiesel Program at Loyola University Chicago Center for Urban Environmental Research and Policy provides a case study of course-based service-learning projects facilitating synergies between the university and the community while concomitantly fostering urban sustainability. This article discusses the program’s design andstructure, and describes specific examples of community partnerships that havebenefited the university, the community, and the environment


Mysterious Mycorrhizae? A Field Trip And Classroom Experiment To Demystify The Symbioses Formed Between Plants And Fungi, Nancy C. Johnson, V. Bala Chaudhary, Jason D. Hoeksema, John C. Moore, Anne Pringle Sep 2009

Mysterious Mycorrhizae? A Field Trip And Classroom Experiment To Demystify The Symbioses Formed Between Plants And Fungi, Nancy C. Johnson, V. Bala Chaudhary, Jason D. Hoeksema, John C. Moore, Anne Pringle

School of Environmental Sustainability: Faculty Publications and Other Works

No abstract provided.


Untangling The Biological Contributions To Soil Stability In Semiarid Shrublands, V. Bala Chaudhary, Matthew A. Bowker, Thomas E. O'Dell, James B. Grace, Andrea E. Redman, Mathias C. Rillig, Nancy C. Johnson Jan 2009

Untangling The Biological Contributions To Soil Stability In Semiarid Shrublands, V. Bala Chaudhary, Matthew A. Bowker, Thomas E. O'Dell, James B. Grace, Andrea E. Redman, Mathias C. Rillig, Nancy C. Johnson

School of Environmental Sustainability: Faculty Publications and Other Works

Communities of plants, biological soil crusts (BSCs), and arbuscular mycorrhizal (AM) fungi are known to influence soil stability individually, but their relative contributions, interactions, and combined effects are not well understood, particularly in arid and semiarid ecosystems. In a landscape-scale field study we quantified plant, BSC, and AM fungal communities at 216 locations along a gradient of soil stability levels in southern Utah, USA. We used multivariate modeling to examine the relative influences of plants, BSCs, and AM fungi on surface and subsurface stability in a semiarid shrubland landscape. Models were found to be congruent with the data and explained …


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.