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

Digital Commons Network

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

Articles 1 - 12 of 12

Full-Text Articles in Entire DC Network

The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang Aug 2021

The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang

Electronic Theses and Dissertations

The Gulf of Maine northern shrimp (Pandalus borealis) once supported a significant winter fishery for the Gulf of Maine (GOM). Although the shrimp fishery is not comparable to the lobster business, it provided fishermen and many coastal communities jobs and incomes in winters after lobster seasons. However, a moratorium has been put on the shrimp fishery since 2014 due to record low population abundance and perceived recruitment failures. The recruitment failures have been correlated with warming water temperatures over the past decade. The GOM has been recognized as experiencing rapid warming as a result of global climate change. …


Assessing The Effectiveness Of Attractants To Increase Detection Probabilities In Northeastern Mammals, Michael Buyaskas Apr 2019

Assessing The Effectiveness Of Attractants To Increase Detection Probabilities In Northeastern Mammals, Michael Buyaskas

Honors College

A primary problem with camera trapping in wildlife occupancy studies is the failure to detect an animal when it is present at the site. My objective was to determine the optimal attractant setup for maximizing detection probabilities of northeast mammalian communities. I carried out an camera trapping project in northern Maine, USA from August to November 2018, and tested 3 distinct attractant setup. Sampling stations consisted of four camera units, and each sampling unit constituted either a treatment or a control: 1) bait + lure (treatment), 2) bait only (treatment), 3) lure only (treatment), and 4) camera only (control). Data …


The Relative Importance Of Aquatic And Terrestrial Variables For Frogs In An Urbanizing Landscape: Key Insights For Sustainable Urban Development, Nélida R. Villaseñora, Don A. Driscoll, Philip Gibbons, Aram J K Calhoun, David B. Lindenmayer Jan 2017

The Relative Importance Of Aquatic And Terrestrial Variables For Frogs In An Urbanizing Landscape: Key Insights For Sustainable Urban Development, Nélida R. Villaseñora, Don A. Driscoll, Philip Gibbons, Aram J K Calhoun, David B. Lindenmayer

Publications

Globally, urbanization threatens ∼950 amphibian species with extinction. Yet a lack of knowledge on the factors influencing common and infrequently encountered species in landscapes that are under increasing pressure from urban development is limiting effective conservation. We examined the relative importance of aquatic variables (pond) and terrestrial variables (at three spatial scales: 10 m, 100 m and 1 km), for commonly and infrequently encountered frogs in an urbanizing forested landscape in southeastern Australia. Species richness and the occurrence of four common species were influenced by the aquatic environment (water body size, aquatic vegetation). Species richness also decreased with increasing urbanization …


Rapid: Ecological Resistance Of Multiply Stressed Populations: The Response Of Tidal Marsh Birds And Plants To Hurricane Sandy, Brian J. Olsen, Chris S. Elphick, Greg Shriver Aug 2015

Rapid: Ecological Resistance Of Multiply Stressed Populations: The Response Of Tidal Marsh Birds And Plants To Hurricane Sandy, Brian J. Olsen, Chris S. Elphick, Greg Shriver

University of Maine Office of Research Administration: Grant Reports

All animal and plant populations can weather change. However, the amount of environmental change a population can absorb is likely to depend upon other, past and ongoing stresses that the population experiences. This project will test whether the ability of populations of native plants and animals in coastal marshes to withstand the recent, extreme storm Hurricane Sandy was greater or less in marshes more subject to past stresses. Researchers will compare the abundances of marsh plants and animals before and after the storm and test whether vulnerability was greater in more specialized species or in marshes surrounded by development, invaded …


Bayesian Analysis Of Data On Nest Success For Marsh Birds, Sean Hardy May 2013

Bayesian Analysis Of Data On Nest Success For Marsh Birds, Sean Hardy

Honors College

Bayesian methods are an increasingly popular form of statistical analysis which uses informative prior distributions to help calculate posterior distributions of models that represent different hypotheses. Frequentist methods are contrasting methods that are used more commonly and more well known, but have come under recent criticism. I examined data gathered by Ellen Robertson, who used information theoretic methods for a Masters’ Thesis in Ecology and Environmental Science at the University of Maine to analyze the daily survival probabilities of marsh birds with a Bayesian perspective in order to get a sense of the Bayesian analysis. Results were as expected; when …


Marine Ecology Of Gulf Of Maine Atlantic Salmon -- Summary Document From A 2008-2010 Series Of Workshops, Maine Sea Grant Feb 2012

Marine Ecology Of Gulf Of Maine Atlantic Salmon -- Summary Document From A 2008-2010 Series Of Workshops, Maine Sea Grant

Maine Sea Grant Publications

Present-day Atlantic salmon losses at sea are higher than documented prior to 1990 but scientists and managers are often overwhelmed at the scale of the issue and multiple unknowns. This is confounded by the small biomass of salmon in a large ecosystem-- a needle in a haystack.

Maine Sea Grant provided convening and facilitation services to a project sponsored by NOAA Fisheries to bring together marine scientists of multiple disciplines to discuss and develop:

1) testable hypotheses to advance our understanding of current low marine survival of Atlantic salmon and

2) management prescriptions to increase marine survival. A series of …


Effects Of Fish Introductions On The Geographic Distribution And Native Invertebrate Biodiversity Of Naturally Fishless Lakes In Maine, Emily Gaenzle Schilling Aug 2008

Effects Of Fish Introductions On The Geographic Distribution And Native Invertebrate Biodiversity Of Naturally Fishless Lakes In Maine, Emily Gaenzle Schilling

Electronic Theses and Dissertations

Widespread fish stocking has led to a worldwide decline in naturally fishless lakes and their associated communities. Little is known about the historical distribution or native communities of these freshwater ecosystems. The objectives of this study were to: 1) develop a quantitative method to remotely detect naturally fishless lakes in Maine, 2) conduct a landscape-scale assessment of unique attributes of fishless lake macroinvertebrate communities, 3) identify macroinvertebrate bioindicators of fish absence, and 4) assess effects of introduced fish on native macroinvertebrates. I identified two physiographic types of naturally fishless lakes in Maine: kettle lakes in the eastern lowlands and foothills …


Implications Of Spatial Autocorrelation And Dispersal For The Modeling Of Species Distributions, Volker Bahn Aug 2005

Implications Of Spatial Autocorrelation And Dispersal For The Modeling Of Species Distributions, Volker Bahn

Electronic Theses and Dissertations

Modeling the geographical distributions of wildlife species is important for ecology and conservation biology. Spatial autocorrelation in species distributions poses a problem for distribution modeling because it invalidates the assumption of independence among sample locations. I explored the prevalence and causes of spatial autocorrelation in data from the Breeding Bird Survey, covering the conterminous United States, using Regression Trees, Conditional Autoregressive Regressions (CAR), and the partitioning of variance. I also constructed a simulation model to investigate dispersal as a process contributing to spatial autocorrelation, and attempted to verify the connection between dispersal and spatial autocorrelation in species' distributions in empirical …


Modeling Bird Species Occurrence In Current And Future Landscapes, Stephen Nicholas Matthews May 2003

Modeling Bird Species Occurrence In Current And Future Landscapes, Stephen Nicholas Matthews

Electronic Theses and Dissertations

With mounting evidence that global temperatures have increased significantly over the last century and the projections of greater changes in climate by the end of this century, understanding the potential consequences of these changes for species is essential to conservation efforts. Here I evaluate the potential response of birds to projected climate change by using regression tree analysis to create models of species distributions under current conditions from Breeding Bird Survey data and then project these models onto General Circulation Model (GCM) scenarios of global climate change. Before modeling species responses to climate change, I selected seventeen bird species to …


Tb117: Techniques For Using The Growth And Behavior Of Imprinted Ducklings To Evaluate Habitat Quality, Malcolm L. Hunter Jr., Jack W. Witham, Jody Jones Apr 1985

Tb117: Techniques For Using The Growth And Behavior Of Imprinted Ducklings To Evaluate Habitat Quality, Malcolm L. Hunter Jr., Jack W. Witham, Jody Jones

Technical Bulletins

We developed a technique for evaluating duckling habitat quality that is based on two assumptions. In good habitat young birds (1) grow rapidly and thus are better able t o survive stresses such as inclement weather, and (2) spend relatively less time moving about in search of food and more time resting and thus are less conspicuous to predators. We imprinted artificially incubated and hatched ducklings by being present at the time of hatching; i.e., the ducklings thought we were their mother. Ducklings were split into broods and placed on ponds where their growth was measured and their behavior monitored …


Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix I: Visual-Recreation Resources Impact Study, United States Department Of Energy Jan 1978

Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix I: Visual-Recreation Resources Impact Study, United States Department Of Energy

Dickey-Lincoln School Lakes Project

The U.S. Departments of the Interior and Energy have conducted system planning, location, and environmental studies for the transmission facilities required for the Dickey-Lincoln School Hydroelectric Project. These studies of many alternate routes have resulted in identification of a proposed transmission line route, and an environmental impact statement as required by the National Environmental Policy Act of 1969. This report, one of several covering various topical areas, is published as an appendix to that statement.


Recommendations Of Alternative System Plans And Transmission Corridors For The Dickey/Lincoln School Hydroelectric Project, Vtn Environmental Sciences (Firm), Interior Jan 1976

Recommendations Of Alternative System Plans And Transmission Corridors For The Dickey/Lincoln School Hydroelectric Project, Vtn Environmental Sciences (Firm), Interior

Dickey-Lincoln School Lakes Project

This second volume of the Assessment of Alternative Power Transmission Corri-dors related to the Dickey Lincoln/School Hydroelectric Project, contains all relevant background materials to support the mapping and analysis of en-vironmental resource information. Narrative explaining what information was evaluated and the sources and reasons for its consideration are integral to this assessment.