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Full-Text Articles in Life Sciences

A Comparison Of Fuel Reduction Methods For Wildfire Risk Management And Climate Change Resiliency In Mixed Conifer Forests In The Sierra Nevada, Heather Navle May 2020

A Comparison Of Fuel Reduction Methods For Wildfire Risk Management And Climate Change Resiliency In Mixed Conifer Forests In The Sierra Nevada, Heather Navle

Master's Projects and Capstones

Wildfires in the mixed conifer forests of California’s Sierra Nevada have been a common and natural disturbance for thousands of years, historically occurring every 3 to 30 years. The flora and fauna of the mixed conifer forest have evolved to depend on low to moderate severity wildfires for reproduction, foraging, and habitat. However, the Sierra Nevada has experienced dramatic environmental changes over the past ~150 years as a result of three main factors: wildfire suppression, climate change, and habitat loss. Because of the threat wildfires pose to human lives, property and timber harvest, they have been suppressed to an ...


Understanding Global Change: From Documentation And Collaboration To Social Transformation, Karen E. Pennesi Jan 2020

Understanding Global Change: From Documentation And Collaboration To Social Transformation, Karen E. Pennesi

Anthropology Publications

The conclusion to the book situates the chapters within four programs of anthropological research on climate change: (1) documentation of local impacts of and adaptations to climate change, (2) connections to socioeconomic and political contexts, (3) collaborations with nonanthropologists, and (4) activism and social transformation. The final section notes the persistent challenges to creating positive change and meaningful research outcomes. It highlights some examples of success and outlines future directions for politically engaged anthropological work around climate change.


Watching Grass Grow: How Soil Moisture Affects Vesicular-Arbuscular Mycorrhizae And Growth In Little Bluestem, Laura M. Jones Dec 2019

Watching Grass Grow: How Soil Moisture Affects Vesicular-Arbuscular Mycorrhizae And Growth In Little Bluestem, Laura M. Jones

Honors Scholar Theses

Vesicular-arbuscular mycorrhizae (VAM) are an ancient mutualism in which soil-dwelling fungi enhance plant absorption of phosphorus and nitrogen in exchange for photosynthates. VAM are sensitive to changes in soil moisture and nutrient content, fluctuating between mutualism and parasitism depending on conditions of drought stress and nutrient deficiency. Understanding how VAM respond to precipitation changes is crucial for both conservation and agricultural purposes. To test how soil moisture changes the effects of VAM colonization and growth in little bluestem (Schizachyrium scoparium), a common prairie grass, I planted 300 seeds in a greenhouse in sterilized soil and soil inoculated with VAM fungi ...


Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith Dec 2019

Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith

Faculty Publications in the Biological Sciences

The catastrophic loss of large-bodied mammals during the terminal Pleistocene likely led to cascading effects within communities. While the extinction of the top consumers probably expanded the resources available to survivors of all body sizes, little work has focused on the responses of the smallest mammals. Here, we use a detailed fossil record from the southwestern United States to examine the response of the hispid cotton rat Sigmodon hispidus to biodiversity loss and climatic change over the late Quaternary. In particular, we focus on changes in diet and body size. We characterize diet through carbon (δ13C) and nitrogen ...


Iceland's Migratory Birds In Changing Environmental Conditions: An Interactive Synthesis, Frances J. Duncan Apr 2019

Iceland's Migratory Birds In Changing Environmental Conditions: An Interactive Synthesis, Frances J. Duncan

Independent Study Project (ISP) Collection

Human-driven changes to environmental conditions alter the habitats, behaviors, and migration patterns of migratory species. Changes in temperature, vegetation, and precipitation are just some of the factors contributing to shifts in phenology, demography, and distribution of migratory birds. These changes are driven by anthropogenic climate change and amplified by human land-use change, and are especially intense at high latitudes. This project creatively communicates the effects of environmental changes on three species of migratory birds in Iceland—the northern wheatear, the Greenland white-fronted goose, and the black-tailed godwit—using principles of storytelling and game design. The resulting interactive product is a ...


Range Expansion Or Range Shift? Population Genetics And Historic Range Data Analyses Of The Predatory Benthic Sea Slug Phidiana Hiltoni (Mollusca, Gastropoda, Nudibranchia), Clara Jo King, Ryan Ellingson, Jeffrey H. R. Goddard, Rebecca F. Johnson, Angel A. Valdes Jan 2019

Range Expansion Or Range Shift? Population Genetics And Historic Range Data Analyses Of The Predatory Benthic Sea Slug Phidiana Hiltoni (Mollusca, Gastropoda, Nudibranchia), Clara Jo King, Ryan Ellingson, Jeffrey H. R. Goddard, Rebecca F. Johnson, Angel A. Valdes

Bulletin of the Southern California Academy of Sciences

Phidiana hiltoni is a conspicuous nudibranch sea slug native to the northeastern Pacific Ocean. Over the past thirty years the range of P. hiltoni has expanded about 200 km northward, but the mechanism that facilitated this expansion is poorly understood. In this study, we use mtDNA and microsatellite data to investigate the population structure of P. hiltoni in its historical range as well as in recently colonized localities. Microsatellite analyses reveal little to no genetic structure and thus high gene flow throughout the range of P. hiltoni. This is consistent with mtDNA analysis results, which revealed shared haplotypes between Southern ...


Shade Trees Preserve Avian Insectivore Biodiversity On Coffee Farms In A Warming Climate, Sarah L. Schooler Jan 2019

Shade Trees Preserve Avian Insectivore Biodiversity On Coffee Farms In A Warming Climate, Sarah L. Schooler

HSU theses and projects

Coffee is an important export in many developing countries, with a global annual trade value of $100 billion. Climate change is projected to drastically reduce the area where coffee is able to be grown. Shade trees may mitigate the effects of climate change through temperature regulation for coffee growth, temperature regulation for pest control, and increase in pest-eating bird diversity. The impact of shade on bird diversity and microclimate on coffee farms has been studied extensively in the Neotropics, but there is a dearth of research in the Paleotropics. I examined the local effects of shade on bird presence and ...


A Multi-Scale Analysis Of Jaguar (Panthera Onca) And Puma (Puma Concolor) Habitat Selection And Conservation In The Narrowest Section Of Panama., Kimberly A. Craighead Jan 2019

A Multi-Scale Analysis Of Jaguar (Panthera Onca) And Puma (Puma Concolor) Habitat Selection And Conservation In The Narrowest Section Of Panama., Kimberly A. Craighead

Dissertations & Theses

Over the past two centuries, large terrestrial carnivores have suffered extreme population declines and range contractions resulting from the synergistic anthropogenic threats of land-use change and indirect effects of climate change. In Panama, rapid land use conversion coupled with climate change is predicted to negatively impact jaguar (Panthera onca) and puma (Puma concolor). This dissertation examined the environmental variables and scales influencing jaguar and puma habitat selection by season (annual, wet, and dry), using multi-scale optimized habitat suitability models and a machine-learning algorithm (Random Forests), in the narrowest section of Panama. The models derived from the data of an intensive ...


Ecological And Societal Services Of Aquatic Diptera, Peter H. Adler, Gregory W. Courtney Jan 2019

Ecological And Societal Services Of Aquatic Diptera, Peter H. Adler, Gregory W. Courtney

Entomology Publications

More than any other group of macro-organisms, true flies (Diptera) dominate the freshwater environment. Nearly one-third of all flies—roughly 46,000 species—have some developmental connection with an aquatic environment. Their abundance, ubiquity, and diversity of adaptations to the aquatic environment position them as major drivers of ecosystem processes and as sources of products and bioinspiration for the benefit of human society. Larval flies are well represented as ecosystem engineers and keystone species that alter the abiotic and biotic environments through activities such as burrowing, grazing, suspension feeding, and predation. The enormous populations sometimes achieved by aquatic flies can ...


Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller Dec 2018

Understanding The Impacts Of Current And Future Environmental Variation On Central African Amphibian Biodiversity, Courtney A. Miller

University of New Orleans Theses and Dissertations

Global climate change is projected to impact multiple levels of biodiversity by imposing strong selection pressures on existing populations, triggering shifts in species distributions, and reorganizing entire communities. The Lower Guineo-Congolian region in central Africa, a reservoir for amphibian diversity, is predicted to be severely affected by future climate change through rising temperatures and greater variability in rainfall. Geospatial modelling can be used to assess how environmental variation shapes patterns of biological variation – from the genomic to the community level – and use these associations to predict patterns of biological change across space and time. The overall goal of this dissertation ...


Survival At The Summits: Amphibian Responses To Thermal Extremes, Disease, And Rapid Climate Change In The High Tropical Andes, Kelsey E. Reider Sep 2018

Survival At The Summits: Amphibian Responses To Thermal Extremes, Disease, And Rapid Climate Change In The High Tropical Andes, Kelsey E. Reider

FIU Electronic Theses and Dissertations

Understanding biological responses to climate change is a primary concern in conservation biology. Of the ecosystems being rapidly impacted by climate change, those in the high-elevation tropics are among the most poorly studied. The tropical Andean biosphere includes record elevations above 5000 meters, where extreme environmental conditions challenge many organisms. In the Cordillera Vilcanota of southern Peru, frogs including Pleurodema marmoratum and Telmatobius marmoratus have expanded their ranges to 5244 – 5400 m into habitats created by glacial recession, making them among the highest recorded amphibians on Earth. To understand how hydrologic alterations from loss of glacial meltwater and climatic fluctuations ...


Simulation Code For Intraspecific Variability May Not Compensate For Increasing Climatic Volatility, George P. Malanson Jul 2018

Simulation Code For Intraspecific Variability May Not Compensate For Increasing Climatic Volatility, George P. Malanson

Research Data

The role of intraspecific variability is being examined to improve predictions of responses to climate change or invasions and in research on diversity. Simultaneously, the probability and implications of increased high-frequency climate variability have been raised. An agent based model simulated two species on an environmental gradient representing an alpine treeline; a trend in its volatility was added. The species have different levels of variability, and each individual has further unique heterogeneity. Environmental volatility and individual heterogeneity were based on tree ring data from Pinus albicaulis. Simulations show that increasing volatility leads to population declines, including extinctions, and to sharper ...


A Quantitative Analysis Of The Effects Of Urbanization, Mesophication And Prescribed Burns On Oak Woodlands In The Chicago Metropolitan Area, Chad Populorum May 2018

A Quantitative Analysis Of The Effects Of Urbanization, Mesophication And Prescribed Burns On Oak Woodlands In The Chicago Metropolitan Area, Chad Populorum

Celebration of Learning

Urban expansion has had devastating impacts on forest ecosystems, especially within the past century. Human attempts to dominate nature have diminished natural disturbance regimes, which have maintained the biodiversity and historic composition of these ecosystems. Fires have been a prominent force in maintaining the structure of oak, hickory and other heliophytic (sun loving and fire-adapted) forest systems. Human induced fire suppression has led to mesophication across North America. Mesophication is the transition from drier conditions with open canopies to wetter conditions with closed canopies. These new conditions decrease the survival rates of these important species and begin to favor mesophytic ...


In Anthropocene Air: Deleuze's Encounter With Shakespeare, Steven Swarbrick Jan 2018

In Anthropocene Air: Deleuze's Encounter With Shakespeare, Steven Swarbrick

Publications and Research

No abstract provided.


Physiological Ecology Of Four Endemic Alabama Species And The Exotic Asiatic Weatherfish, Misgurnus Anguillicaudatus (Cantor, 1842), Lindsay M. White, Mark E. Meade, Benjamin A. Staton Sep 2017

Physiological Ecology Of Four Endemic Alabama Species And The Exotic Asiatic Weatherfish, Misgurnus Anguillicaudatus (Cantor, 1842), Lindsay M. White, Mark E. Meade, Benjamin A. Staton

Southeastern Fishes Council Proceedings

The occurrence of Asiatic Weatherfish, Misgurnus anguillicaudatus, in Alabama, a state known for its rich biodiversity, has generated concern among conservation managers. The current study used respirometry techniques to investigate the effects of increasing temperature on four native southeastern fishes (one cyprinid, two percids, and one elassomid) and the non-native M. anguillicaudatus. A minimum of five individuals of each species were used, and three experimental temperatures were chosen to represent spring and summer averages of northeast Alabama streams (15, 20, and 25°C). Overall, mean standard metabolic rates (SMRs) for M. anguillicaudatus were low (97.01, 127.75, and 158 ...


Using Regional Climate Projections To Guide Grassland Community Restoration In The Face Of Climate Change, Kristin Kane, Diane M. Debinski, Chris Anderson, John D. Scasta, David M. Engle, James R. Miller May 2017

Using Regional Climate Projections To Guide Grassland Community Restoration In The Face Of Climate Change, Kristin Kane, Diane M. Debinski, Chris Anderson, John D. Scasta, David M. Engle, James R. Miller

Ecology, Evolution and Organismal Biology Publications

Grassland loss has been extensive worldwide, endangering the associated biodiversity and human well-being that are both dependent on these ecosystems. Ecologists have developed approaches to restore grassland communities and many have been successful, particularly where soils are rich, precipitation is abundant, and seeds of native plant species can be obtained. However, climate change adds a new filter needed in planning grassland restoration efforts. Potential responses of species to future climate conditions must also be considered in planning for long-term resilience. We demonstrate this methodology using a site-specific model and a maximum entropy approach to predict changes in habitat suitability for ...


A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London Jan 2017

A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London

HSU theses and projects

Intermittent streams are common throughout the world and comprise 60% or more of total river lengths in the conterminous United States. Despite their prevalence, intermittent streams are understudied, particularly first-order headwater streams, which are vital for maintaining the function, health and biotic diversity of river networks. In June 2016, I sampled five intermittent and five perennial headwater streams in the Mattole River watershed in northwestern coastal California, USA, to compare benthic macroinvertebrate (BMI) assemblages between intermittent and perennial streams. BMI samples were collected using a 500µm mesh D-net at eight randomly located riffles along a 150-m reach, and then composited ...


The Impacts Of Climate Change On Communities Of Fungi In Boreal Peatlands, Asma Asemaninejad Hassankiadeh Dec 2016

The Impacts Of Climate Change On Communities Of Fungi In Boreal Peatlands, Asma Asemaninejad Hassankiadeh

Electronic Thesis and Dissertation Repository

Peatlands have an important role in global climate change through sequestration of atmospheric CO2. Climate change is already affecting these ecosystems, including both above- and below- ground communities and their functions. Fungi play a central role in these communities. As a result, there is concern that altered fungal community function may turn peatlands from carbon sinks to carbon sources, greatly exacerbating the impacts of climate change. In order to gain a better insight into effects of climate change on the structure and function of these carbon sequestrating ecosystems, this thesis focuses on diversity and structure of fungal communities in ...


Biodiversity Of Medicinal Plants In The Highlands: Problems And Perspectives, Vyacheslav Dushenkov Jul 2016

Biodiversity Of Medicinal Plants In The Highlands: Problems And Perspectives, Vyacheslav Dushenkov

Publications and Research

Climate change is affecting medicinal plants around the world and could ultimately lead to losses of some key species, in particular species endemic to a region and causing plants to migrate to new ranges. As the situation unfolds, climate change may become a pressing issue for the herbal community, affecting medicinal plant supply chains with varying requirements for plant cultivation, resource management in the wild, harvesting, processing, and importantly marketing.


Estimated Effects Of Climate Change On The Reproductive Fitness Of The Northern Spotted Owl, Strix Occidentalis Caurina, Nadia Swit May 2016

Estimated Effects Of Climate Change On The Reproductive Fitness Of The Northern Spotted Owl, Strix Occidentalis Caurina, Nadia Swit

The Downtown Review

In this paper, the trends for current and future climate change were utilized to evaluate the potential reproductive success of the Spotted Owl, particularly the Northern Spotted Owl (Strix occidentalis caurina) subspecies. As breeding season would exert additional stressors on the animal, a time period of five months, from January to June, was selected for the spring breeding season in which to evaluate temperature change. Previous research performed by Weathers and colleagues (2001) concerning the California Owl (Strix occidentalis occidentalis) formulated a thermodynamic equation that was utilized to compare the metabolic rate of the owl at current and future environmental ...


Consensus On Consensus: A Synthesis Of Consensus Estimates On Human-Caused Global Warming, John Cook, Naomi Oreskes, Peter T. Doran, William R L Anderegg, Bart Verheggen, Ed W. Maibach, J Stuart Carlton, Stephan Lewandowsky, Andrew G. Skuce, Sarah A. Green, Dana Nuccitelli, Peter Jacobs, Mark Richardson, Bärbel Winkler, Rob Painting, Ken Rice Apr 2016

Consensus On Consensus: A Synthesis Of Consensus Estimates On Human-Caused Global Warming, John Cook, Naomi Oreskes, Peter T. Doran, William R L Anderegg, Bart Verheggen, Ed W. Maibach, J Stuart Carlton, Stephan Lewandowsky, Andrew G. Skuce, Sarah A. Green, Dana Nuccitelli, Peter Jacobs, Mark Richardson, Bärbel Winkler, Rob Painting, Ken Rice

Department of Chemistry Publications

The consensus that humans are causing recent global warming is shared by 90%–100% of publishing climate scientists according to six independent studies by co-authors of this paper. Those results are consistent with the 97% consensus reported by Cook et al(Environ. Res. Lett. 8 024024) based on 11 944 abstracts of research papers, of which 4014 took a position on the cause of recent global warming. A survey of authors of those papers (N = 2412 papers) also supported a 97% consensus. Tol (2016 Environ. Res. Lett.11 048001) comes to a different conclusion using results from surveys of non-experts ...


A Review Of Fall Sandhill Crane Migration Through Indiana, Allisyn-Marie T. Y. Gillet Jan 2016

A Review Of Fall Sandhill Crane Migration Through Indiana, Allisyn-Marie T. Y. Gillet

Proceedings of the North American Crane Workshop

The Indiana Division of Fish and Wildlife conducts surveys from October to December to collect long-term data on greater sandhill cranes (Grus canadensis tabida). Results from these censuses contribute to a fall index of the Eastern Population, which informs wildlife management decisions and research priorities. Recent findings from the annual U. S. Fish and Wildlife Service Fall Sandhill Crane Migration Survey demonstrate a decline in the number of cranes observed at fall staging areas throughout Indiana since 1979. However, nationwide data exhibit a trend of population increase. I provide evidence to show that the apparent decline in the number of ...


At Home And At Large In The Great Plains: Essays And Memories, Paul A. Johnsgard Jul 2015

At Home And At Large In The Great Plains: Essays And Memories, Paul A. Johnsgard

Zea E-Books

This volume presents fourteen essays (some updated) that originally appeared in Prairie Fire, a monthly free newspaper that for seven years (as of 2015) has carried important messages of social, environmental, and economic issues in a mature and nonpartisan manner to tens of thousands of residents of Nebraska, western Iowa, eastern Colorado, and southern South Dakota, and by mail to subscribers in the rest of the world. These essays discuss the North American east-west ecological boundaries, spring migration events, birds at the bird feeder, feathered survivors of a glacial past, the threatened sharp-tailed grouse of Nebraska and South Dakota, and ...


Agenda: Seeds Of Change: Responding To Global Change In A Bottom-Up World, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment, University Of Colorado Boulder. School Of Law, Posner Center For International Development, Resolve (Firm), Newmont Mining Corporation Feb 2015

Agenda: Seeds Of Change: Responding To Global Change In A Bottom-Up World, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment, University Of Colorado Boulder. School Of Law, Posner Center For International Development, Resolve (Firm), Newmont Mining Corporation

Seeds of Change: Responding to Global Change in a Bottom-Up World (Martz Winter Symposium, February 12-13)

Sponsors: Posner Center for International Development, RESOLVE, Inc., Newmont Mining Corporation, and Getches-Wilkinson Center for Natural Resources, Energy, and the Environment.

Conference moderators, panelists and speakers included University of Colorado Law School professors Phil Weiser, Sarah Krakoff, Britt Banks, and Lakshman Guruswamy.

This conference is made possible through the generous support of donors who sponsored this year’s Martz Sustainability Symposium (including Newmont Mining Corporation) and those who have invested in our Clyde O. Martz Endowed Fund for Natural Resources Management (including Brian Dolan and Davis Graham and Stubbs LLP). The Martz Natural Resources Management Fund was established in the ...


Navigating A Pathway Toward Colorado's Water Future: A Review And Recommendations On Colorado's Draft Water Plan, Lawrence J. Macdonnell, Colorado Water Working Group Jan 2015

Navigating A Pathway Toward Colorado's Water Future: A Review And Recommendations On Colorado's Draft Water Plan, Lawrence J. Macdonnell, Colorado Water Working Group

Books, Reports, and Studies

40 pages (includes color illustrations).


Syllabus: Sustainable Living: Solutions For The 21st Century, Laurie Simmons Jan 2015

Syllabus: Sustainable Living: Solutions For The 21st Century, Laurie Simmons

Sustainability Education Resources

Your generation has been handed an opportunity: the opportunity to change the story of our culture from one of blind consumption to one of conscious ecological living. As individuals, as a society and as a species, we are facing challenges related to sustainability including economic stability, social justice, resource depletion and waste management, biodiversity preservation, climate adaptation and food and agricultural resilience. In this interdisciplinary course you will learn how to seize this opportunity by working with your peers to research and understand how sustainability in different contexts presents solutions to many of these challenges facing modern society. “Sustainable Living ...


Integrated Modeling Of Land Use And Climate Change Impacts On Multiscale Ecosystems Of Central African Watersheds, Simon Nampindo Nov 2014

Integrated Modeling Of Land Use And Climate Change Impacts On Multiscale Ecosystems Of Central African Watersheds, Simon Nampindo

Doctoral Dissertations

Assessment and management of ecosystem services demands diverse knowledge of the system components. Land use change occurring mainly through deforestation, expansion of agriculture and unregulated extraction of natural resources are the greatest challenges of the Congo basin and yet is central to supporting over 100 million people. This study undertook to implement an integrated modeling of multiscale ecosystems of central African watersheds and model the impact of anthropogenic factors on elephant population in Greater Virunga landscape. The study was conducted at varied scales, regional, landscape, and community. Regional study included watershed analysis and hydrological assessment using remotely sensed data implemented ...


A Threat To New Zealand's Tuatara Heats Up, Kristine L. Grayson, Nicola J. Mitchell, Nicola J. Nelson Sep 2014

A Threat To New Zealand's Tuatara Heats Up, Kristine L. Grayson, Nicola J. Mitchell, Nicola J. Nelson

Biology Faculty Publications

No matter how many times we head to one of New Zealand's offshore islands, the feelings are always a mix of sheer awe at the beauty and biodiversity preserved in these special refuges and lingering nerves. Did we remember all the gear? Do we have enough food and water in case we get stuck? Can the helicopter land on the side of a cliff in these winds? These epic journeys are in pursuit of a lone remnant of the reptile evolutionary tree, with a unique ecology that has big implications under climate change.


Sex Ratio Bias And Extinction Risk In An Isolated Population Of Tuatara (Sphenodon Punctatus), Kristine L. Grayson, Nicola J. Mitchell, Joanne M. Monks, Susan N. Keall, Joanna N. Wilson, Nicola J. Nelson Apr 2014

Sex Ratio Bias And Extinction Risk In An Isolated Population Of Tuatara (Sphenodon Punctatus), Kristine L. Grayson, Nicola J. Mitchell, Joanne M. Monks, Susan N. Keall, Joanna N. Wilson, Nicola J. Nelson

Biology Faculty Publications

Understanding the mechanisms underlying population declines is critical for preventing the extinction of endangered populations. Positive feedbacks can hasten the process of collapse and create an ‘extinction vortex,’ particularly in small, isolated populations. We provide a case study of a male-biased sex ratio creating the conditions for extinction in a natural population of tuatara (Sphenodon punctatus) on North Brother Island in the Cook Strait of New Zealand. We combine data from long term mark-recapture surveys, updated model estimates of hatchling sex ratio, and population viability modeling to measure the impacts of sex ratio skew. Results from the mark-recapture surveys show ...


Effects Of Disturbance And Climate Change On Ecosystem Performance In The Yukon River Basin Boreal Forest, Bruce K. Wylie, Matthew Rigge, Brian Brisco, Kevin Murnaghan, Jennifer A. Rover Jan 2014

Effects Of Disturbance And Climate Change On Ecosystem Performance In The Yukon River Basin Boreal Forest, Bruce K. Wylie, Matthew Rigge, Brian Brisco, Kevin Murnaghan, Jennifer A. Rover

Bruce K. Wylie

A warming climate influences boreal forest productivity, dynamics, and disturbance regimes. We used ecosystem models and 250 m satellite Normalized Difference Vegetation Index (NDVI) data averaged over the growing season (GSN) to model current, and estimate future, ecosystem performance. We modeled Expected Ecosystem Performance (EEP), or anticipated productivity, in undisturbed stands over the 2000–2008 period from a variety of abiotic data sources, using a rule-based piecewise regression tree. The EEP model was applied to a future climate ensemble A1B projection to quantify expected changes to mature boreal forest performance. Ecosystem Performance Anomalies (EPA), were identified as the residuals of ...