Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Entire DC Network

Evaluating The Ecological Status Of The Introduced Nile Monitor (Varanus Niloticus) In Florida: Forecasting Presence And Population Expansion Using Computational Geographic Information Systems, Noah G. Cohen Nov 2017

Evaluating The Ecological Status Of The Introduced Nile Monitor (Varanus Niloticus) In Florida: Forecasting Presence And Population Expansion Using Computational Geographic Information Systems, Noah G. Cohen

HCNSO Student Theses and Dissertations

The Nile monitor (Varanus niloticus) is a large, carnivorous lizard that has become a notorious invasive species in Florida, USA. Initially released in the 1980s from the pet trade, the species has since established at least three breeding populations and spread throughout much of southern Florida. While current control efforts have failed to eradicate V. niloticus, it is important to attain a better understanding of its invasive dynamics to guide and inform better control strategies. In this study, available georeferenced records of V. niloticus in Florida were compiled and linked to a habitat classification map to evaluate ecotype preferences. Factored …


Ecological Niche Modeling Of The Genus Papio, Amanda J. Fuchs Aug 2017

Ecological Niche Modeling Of The Genus Papio, Amanda J. Fuchs

Theses and Dissertations

Ecological niche modeling investigates how climatic variables have influenced taxonomic diversity in Papio. Models performed well suggesting climatic variables influence the distribution of baboon species. Niche overlap among all possible pairs of taxa determined that species exhibited significantly different niches. The results of these models support a parapatric speciation scenario.


Comparative Biogeography Of North American Pika Parasites: Unraveling A History Driven By Climate Change, Heather M. Toman Apr 2017

Comparative Biogeography Of North American Pika Parasites: Unraveling A History Driven By Climate Change, Heather M. Toman

All NMU Master's Theses

Parasites are an understudied group that can provide important information on ecosystem dynamics and climate change as well as host biogeographic history. I performed a comparative biogeographic study on two endoparasitic helminth lineages associated with pikas (Ochotona) -the tapeworm genus Schizorchis and the pinworm subgenus Labiostomum (Eugenuris). Colonization history across Beringia was assessed using analyses of historical range estimation and tests for simultaneous divergence. Analysis results allow me reject the hypothesis that these parasites colonized the Nearctic during a single glacial cycle, as evidenced by multiple Nearctic and Palearctic lineage pairs that did not diverge simultaneously. This …


Understanding Patterns And Drivers Of Alaskan Fire-Regime Variability Across Spatial And Temporal Scales, Tyler J. Hoecker Jan 2017

Understanding Patterns And Drivers Of Alaskan Fire-Regime Variability Across Spatial And Temporal Scales, Tyler J. Hoecker

Graduate Student Theses, Dissertations, & Professional Papers

Boreal forest and tundra ecosystems are globally important because the mobilization of large carbon stocks, and changes in energy balance could act as positive feedbacks to ongoing climate warming. In Alaska, wildfire is a key driver of ecosystem structure and function, and therefore fire strongly determines the feedbacks between high-latitude ecosystems and the larger Earth system. The paleoecological record from Alaska reveals the sensitivity of fire regimes to climatic and vegetation change over centennial to millennial time scales, highlighting increased burning with warming and/or increased landscape flammability associated with large-scale vegetation changes. This thesis focuses on two studies aimed at …


The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry Jan 2017

The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry

Cal Poly Humboldt theses and projects

Many amphibian species are in decline due to habitat loss and changing climates. Understanding how habitat characteristics and climate influence vital rates, and if they act in concert or in opposition can inform management decisions. This study investigated the potential interaction of canopy cover and climate on early stage vital rates of northern red-legged frogs. Demographic data were collected from sample populations in experimental canopy cover treatments across a latitudinal distribution. Rearing cages were used to estimate hatch success, and mark-recapture surveys to estimate tadpole survival. Ambient air temperature was used as an index of climate because it is easily …