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Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad
Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad
Theses and Dissertations
Population connectivity, particularly in open systems, is an important metric for understanding population-level processes on both ecological and evolutionary timescales. In coastal marine systems, adults are typically sedentary and dispersal occurs primarily during a larval stage when individuals are transported in ocean currents. Because coastal marine populations exist as networks of interconnected subpopulations, variation in the magnitude and extent of population connectivity can have profound effects on population dynamics and species distribution limits. Connectivity is a complex process, affected by a multitude of factors, including adult inputs and physical dispersal, which operate at multiple scales and may interact. This dissertation …
Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco
Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco
Theses and Dissertations
Untangling natural systems’ complexity requires understanding the mechanisms responsible for organisms’ responses to environmental change. Recently, significant advances have been made by recognizing the relevance of direct and indirect effects, which take place when multiple biotic and abiotic factors influence each other. I examined potential direct effects of environmental variables on a predator-prey interaction, as well as potential indirect effects of these variables on the interaction itself. I placed emphasis on behavioral and physiological adaptations, which would potentially contribute/modify these effects. My study system was comprised of a rocky intertidal keystone predator, the sea star Pisaster ochraceus, and its main …
Small Mammals Matter? Linking Plant Invasion, Biotic Resistance, And Climate Change In Post-Fire Plant Communities, Rory Charles O'Connor
Small Mammals Matter? Linking Plant Invasion, Biotic Resistance, And Climate Change In Post-Fire Plant Communities, Rory Charles O'Connor
Theses and Dissertations
The introduction and establishment of exotic species can profoundly alter ecosystems. Two exotic species drastically changing the landscape of deserts in western North America are Bromus tectorum L. and Bromus rubens L. Through the buildup of biomass and slow decomposition rates in deserts these two exotic annual grasses can alter fire regimes that change the plant and animal community dynamics in the ecosystems. To better understand the ecological mechanisms that could restrict or alter the patterns of invasive plant establishment we established a replicated full factorial experiment in the Great Basin and Mojave Desert. The combinations of factors being manipulated …
Wetland Sediment Nutrient Flux In Response To Proposed Hydrologic Reconnection And Climate Warming, James T. Smit
Wetland Sediment Nutrient Flux In Response To Proposed Hydrologic Reconnection And Climate Warming, James T. Smit
Masters Theses
Wetland restoration and creation are common practices, but wetlands restored or created on former agricultural land may act as a source of nutrients, rather than as a sink. I studied P sediment-water exchange in two flooded celery fields (west and east), which are designated for wetland restoration, in order to assess the effects that hydrologic reconnection of the area to an adjacent creek would have on P dynamics. We also examined the influence of climate change, specifically warming temperatures, by conducting the sediment-water exchange experiments at ambient and plus 2°C temperature conditions. Lab-based sediment core incubations revealed that TP release …
Establishment Of Larrea Tridentata At The Northern Edge Of The Modern Mojave Desert: Insights From Neotoma Paleomiddens, Clare Steinberg
Establishment Of Larrea Tridentata At The Northern Edge Of The Modern Mojave Desert: Insights From Neotoma Paleomiddens, Clare Steinberg
Biology ETDs
Shifting climates affect the composition of biological communities. If environmental conditions change sufficiently, new species can invade, leading to large-scale community turnover. Understanding how and why such shifts occur is crucial in this era of anthropogenic global change. Paleontological studies provide a valuable long-term perspective of the dynamics of community turnover. Here, we examine changes in the plant community over the past 34 thousand years in what is now the northern Mojave Desert. This time period includes the last glacial maximum as well as numerous smaller climatic fluctuations in the Holocene and the end of the Pleistocene. We quantified plant …
Changes In Spring Arrival And Fall Departure Dates Of Migratory Birds As An Indication Of Local Climate Change: A Phenological Study Of New York State's Capital Region Using Citizen Science, Olivia C. Townsend
Honors Theses
Climate change is becoming an increasingly important topic of scientific research, and studies commonly analyze biological indicators. Migratory birds are responsive to environmental changes because life cycles depend on finding proper seasonal locations. eBird is a citizen science database launched by the Cornell Lab of Ornithology and National Audubon Society in 2002, and this study focused on eBird data to analyze migratory shifts over the past two decades for the Green-winged Teal (Anas crecca), Northern Pintail (Anas acuta), Bufflehead (Bucephala albeola), Common Goldeneye (Bucephala clangula), Common Merganser (Mergus merganser), Red-breasted Merganser (Mergus serrator), Canada Goose (Branta canadensis), Snow Goose (Chen …
Inferring Herpetofaunal Distributions And Habitat Preferences For Conservation Planning, Lisa M. Prowant
Inferring Herpetofaunal Distributions And Habitat Preferences For Conservation Planning, Lisa M. Prowant
Master's Theses
Global climate change is a serious threat to global biodiversity (IPCC, 2001). Due to their limited dispersal ability, reptiles and amphibians might be more vulnerable to rapid climate change than are other taxonomic groups (Gibbons et al., 2000). Herpetofauna in south-central Kansas was sampled from May through August in 2012 and 2013. Seven study sites spanning Meade, Clark, Comanche, and Barber counties were sampled. Drift fence and cover-board traps were arranged in transects at each site to capture reptiles and amphibians. Species were also sampled through surveys on all-terrain vehicles and on foot. Two thousand nine hundred and forty five …
Range Collapse, Genetic Differentiation, And Climate Change: An Ecological History Of The Diana Fritillary, Speyeria Diana And Projections For Its Future, Carrie Wells
All Dissertations
The geographic ranges of most plant and animal species are tied closely to climatic factors, including temperature, precipitation, and soil moisture. For this reason, recent changes in the global climate due to human activities are predicted to have profound effects on natural populations, communities and ecosystems over a relatively short period of time. Combined effects from global warming and other anthropogenic activities such as land-use changes, pollution, and habitat loss/fragmentation, are altering species' distributions faster than they can be documented. Recent climate change has also been shown to alter species' breeding behaviors and alter the synchrony and timing of species' …
How Important Is Land-Based Foraging To Polar Bears (Ursus Maritimus) During The Ice-Free Season In Western Hudson Bay? An Examination Of Dietary Shifts, Compositional Patterns, Behavioral Observations And Energetic Contributions, Linda J. Gormezano
Dissertations, Theses, and Capstone Projects
Trophic mismatches between predators and their prey are increasing as climate change causes decoupling of phenological relationships. Predators linked to the life histories of a particular prey will have a more difficult time persisting through environmental change unless they can alter their behavior to maintain the historical match or possess the ability to pursue alternate prey. Arctic predators typically possess flexible foraging strategies to survive in the labile environment, however, quantifying the limits of those strategies can be difficult when life history information is incomplete. In such cases, piecing together different aspects of a predator's foraging behavior, particularly when environmental …
Approaches To Restoration: Assessing The Roles Of Structure And Function In Saltmarsh Restoration In Light Of Climate Change, Abby O. Pearson Ms
Approaches To Restoration: Assessing The Roles Of Structure And Function In Saltmarsh Restoration In Light Of Climate Change, Abby O. Pearson Ms
All Student Scholarship
The aim of this thesis is to review the current goals and methods for salt marsh restoration, to question how those goals and methods may change in light of global change, and to present a case study that offers a look at the kinds of information that can be gleaned by studying both structure and functionality in restoration.