[PDF] Developing Species Distribution Models For Wood Turtle Glyptemys Insculpta In Atlantic Canada eBook

Author : Thomas Baker
Publisher :
Page : 0 pages
File Size : 10,89 MB
Release : 2022
Category :
ISBN :

GET BOOK

The wood turtle, Glyptemys insculpta, is listed as threatened federally in Canada and provincially in Nova Scotia (NS) and New Brunswick (NB). Historic surveying for G. insculpta in these provinces has been arbitrary and geographic knowledge gaps persist. To address these gaps, this research developed species distribution models for NS and NB using Maxent software, G. insculpta occurrence data, and environmental data relevant to the species' ecology. Resulting important model variables included 'Elevation', 'Distance to Alder', and 'Watercourse Density'. The model outputs were used to guide field surveys, which recorded G. insculpta occurrences at twelve new sites. In NS, the model output's prediction of G. insculpta distribution overlapped with 80.4% of identified core habitat, but only 4.6% of this predicted distribution was within protected areas. The findings will contribute to conservation of this at-risk species by predicting its distribution, and in doing so, inform future survey efforts and conservation decisions.

Author : Jacqueline Danielle Litzgus
Publisher :
Page : 64 pages
File Size : 26,63 MB
Release : 1996
Category : Endangered species
ISBN :

GET BOOK

Assesses the conservation status of Clemmys insculpta, the wood turtle, which ranges discontinuously in north-eastern North America and is confined to specific habitats associated with streams. Information is included on the turtle's geographic distribution in Canada and the United States, population size and trends, protection status, habitat, general biology, factors limiting the turtle population size and distribution, and the special significance of the species. Concludes with brief discussion of the current consensus regarding the status of the species and a recommendation for designation of the species as vulnerable.

Author : Reid Tingley
Publisher :
Page : pages
File Size : 36,28 MB
Release : 2008
Category :
ISBN :

GET BOOK

I provide two case studies from the herpetofauna of Nova Scotia, Canada to illustrate the effects of using different types of explanatory variables in the development of predictive habitat models. In chapter two, I used radio-telemetry data on a declining species of turtle ('Glyptemys insculpta') to compare models built using GIS data (indirect predictors) to models built using habitat data collected in the field (direct predictors). Spatio-temporal niche partitioning between males and female turtles confounded the importance of field-based variables. The occurrence of males was successfully predicted using GIS data whereas the occurrence of females was best predicted using field-based variables. These results demonstrate the importance of taking a more 'sexually' explicit and temporally dynamic view of the environmental niche. In chapter three, I used data from a recent herpetofaunal atlas to investigate the relative roles of climate, land-cover and spatial autocorrelation in determining the distributions of eight anurans and three freshwater turtles at a 10-km resolution. The inclusion of land-cover significantly increased the performance of bioclimatic models for the majority of species. Accounting for spatial autocorrelation improved model fit for rare species but generally did not improve prediction success. Although the integration of climate and land-cover data is likely to produce more accurate spatial predictions of contemporary biodiversity, further research is needed to determine whether incorporating land-cover and spatial autocorrelation in climate-induced range shift projections is merited. Researchers should more carefully consider the effects of using different types of explanatory variables when making correlative predictions of species distributions at local and regional scales.

Author : Roxanne Duncan
Publisher :
Page : pages
File Size : 14,26 MB
Release : 2012
Category :
ISBN :

GET BOOK

East Pacific green sea turtles, Chelonia mydas, play ecologically important roles in marine habitats which range from grazing (and thus regularly "mowing") algae and seagrass beds to cycling nutrients between the ocean and land. However, these important grazers have been hunted to ecological extinction in some places for their eggs, meat, and skin. The conservation initiative for the survival of sea turtles requires the protection of their primary habitats in conjunction with a decrease in their interaction with humans. One way these objectives can be met is through the creation of species distribution maps (SDMs). For this thesis, a SDM was created from a generalized additive model used to identify major feeding areas for East Pacific green turtles residing in the Galapagos Islands. The input for the model was green turtle sighting locations during a June 2010 marine life observation survey and remotely sensed values of four oceanographic parameters obtained from satellite sensors (Bathymetry, Sea Surface Temperature, Chlorophyll a, and Current Speed). Line transects of intertidal and subtidal shoreline regions of the islands of Isabela, San Cristobal, and Floreana were also completed, to describe similarities and differences in macroalgal abundance between the locations. A generalized additive model (GAM) explained 56% of the data's null deviance and had a true positive rate of 0.83. The corresponding species distribution map indicated that East Pacific green sea turtles prefer to forage in warm, low chlorophyll a, slow moving waters at depths mostly less than 250m throughout the archipelago. ANOVA analyses showed that macroalgal abundance was statistically different (p-value

Author : Carl H. Ernst
Publisher : JHU Press
Page : 840 pages
File Size : 36,94 MB
Release : 2009-06-15
Category : Nature
ISBN : 0801891213

GET BOOK

Winner, 2011 Book Award, The Wildlife Society2009 Outstanding Academic Title, Choice Ernst and Lovich’s thoroughly revised edition of this classic reference provides the most updated information ever assembled on the natural histories of North American turtles. From diminutive mud turtles to giant alligator snappers, two of North America’s most prominent experts describe the turtles that live in the fresh, brackish, and marine waters north of Mexico. Incorporating the explosion of new scientific information published on turtles over the past fifteen years—including the identification of four new species—Ernst and Lovich supply comprehensive coverage of all fifty-eight species, with discussions of conservation status and recovery efforts. Each species account contains information on identification, genetics, fossil record, distribution, geographic variation, habitat, behavior, reproduction, biology, growth and longevity, food habits, populations, predators, and conservation status. The book includes range maps for freshwater and terrestrial species, a glossary of scientific names, an extensive bibliography for further research, and an index to scientific and common names. Logically organized and richly illustrated—with more than two hundred color photographs and fifty-two maps—Turtles of the United States and Canada remains the standard for libraries, museums, nature centers, field biologists, and professional and amateur herpetologists alike.

Author : J. Andrew Royle
Publisher : Elsevier
Page : 463 pages
File Size : 39,70 MB
Release : 2008-10-15
Category : Science
ISBN : 0080559255

GET BOOK

A guide to data collection, modeling and inference strategies for biological survey data using Bayesian and classical statistical methods. This book describes a general and flexible framework for modeling and inference in ecological systems based on hierarchical models, with a strict focus on the use of probability models and parametric inference. Hierarchical models represent a paradigm shift in the application of statistics to ecological inference problems because they combine explicit models of ecological system structure or dynamics with models of how ecological systems are observed. The principles of hierarchical modeling are developed and applied to problems in population, metapopulation, community, and metacommunity systems. The book provides the first synthetic treatment of many recent methodological advances in ecological modeling and unifies disparate methods and procedures. The authors apply principles of hierarchical modeling to ecological problems, including * occurrence or occupancy models for estimating species distribution * abundance models based on many sampling protocols, including distance sampling * capture-recapture models with individual effects * spatial capture-recapture models based on camera trapping and related methods * population and metapopulation dynamic models * models of biodiversity, community structure and dynamics Wide variety of examples involving many taxa (birds, amphibians, mammals, insects, plants) Development of classical, likelihood-based procedures for inference, as well as Bayesian methods of analysis Detailed explanations describing the implementation of hierarchical models using freely available software such as R and WinBUGS Computing support in technical appendices in an online companion web site