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Lophozonia tree cavities used for nesting by Slender-billed Parakeets (Enicognathus leptorhynchus) in the central valley of southern Chile: a potentially vanishing keystone resource

Description: This article describes and quantifies characteristics of southern beech (Lophoonia obliqua) trees and their associated cavities used for nesting by Slender-billed Parakeets in the central valley of southern Chile.
Date: February 6, 2017
Creator: White, Thomas H., Jr. & Jiménez, Jaime E.
Partner: UNT College of Arts and Sciences

A Correlation of the Habitat Factors with the Quantity of Bacterial Colonies as Observed by the Direct Microscopic Method on Twenty Soils of Denton County, Texas

Description: The aim of this study is to determine what factors are most important in controlling the number of bacterial colonies found in twent represntative Denton County (Texas) soils during the growing season.
Date: August 1937
Creator: Roach, Cornelia Ann
Partner: UNT Libraries

Density, Distribution and Habitat Requirements for the Ozark Pocket Gopher (Geomys Bursarius Ozarkensis)

Description: A new subspecies of the plains pocket gopher (Geomys bursarius ozarkensis), located in the Ozark Mountains of north central Arkansas, was recently described by Elrod et al. (2000). Current range for G. b. ozarkensis was established, habitat preference was assessed by analyzing soil samples, vegetation and distance to stream and potential pocket gopher habitat within the current range was identified. A census technique was used to estimate a total density of 3, 564 pocket gophers. Through automobile and aerial survey 51 known fields of inhabitance were located extending the range slightly. Soil analyses indicated loamy sand as the most common texture with a slightly acidic pH and a broad range of values for other measured soil parameters and 21 families of vegetation were identified. All inhabited fields were located within an average of 107.2m from waterways and over 1,600 hectares of possible suitable habitat was identified.
Date: May 2004
Creator: Kershen, Audrey Allbach
Partner: UNT Libraries

L-325 Sagebrush Habitat Mitigation Project: Final Compensation Area Monitoring Report

Description: This document provides a review and status of activities conducted in support of the Fluor Daniel Hanford Company (Fluor), now Mission Support Alliance (MSA), Mitigation Action Plan (MAP) for Project L-325, Electrical Utility Upgrades (2007). Three plantings have been installed on a 4.5-hectare mitigation area to date. This review provides a description and chronology of events, monitoring results, and mitigative actions through fiscal year (FY) 2012. Also provided is a review of the monitoring methods, transect layout, and FY 2012 monitoring activities and results for all planting years. Planting densities and performance criteria stipulated in the MAP were aimed at a desired future condition (DFC) of 10 percent mature sagebrush (Artemisia tridentata ssp wyomingensis) cover. Current recommendations for yielding this DFC are based upon a conceptual model planting of 1000 plants/ha (400/ac) exhibiting a 60-percent survival rate after 5 monitoring years (DOE 2003). Accordingly, a DFC after 5 monitoring years would not be less than 600 plants/ha (240/ac). To date, about 8700 sagebrush plants have been grown and transplanted onto the mitigation site. Harsh site conditions and low seedling survival have resulted in an estimated 489 transplants/ha on the mitigation site, which is 111 plants/ha short of the target DFC. Despite this apparent shortcoming, 71, 91, and 24 percent of the surviving seedlings planted in FY 2007 and FY 2008 and FY 2010, respectively, showed signs of blooming in FY 2012. Blooming status may be a positive indication of future sagebrush recruitment, and is therefore a potential source for reaching the target DFC of 600 plants/ha on this mitigation site over time. Because of the difficulty establishing small transplants on this site, we propose that no additional plantings be considered for this mitigation area and to rely upon the potential recruitment by established seedlings to achieve the mitigation commitment set ...
Date: September 26, 2013
Creator: Durham, Robin E. & Becker, James M.
Partner: UNT Libraries Government Documents Department

Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas

Description: The coexistence of Dipodomys ordii and Perognathus hispidus with Peromyscus maniculatus and Reithrodontomys montanus was studied in a grassland association of central Texas. The food habits of these species were compared with information from habitat vegetation analysis in an effort to determine food selectivity and the amount and importance of niche overlap and competition among these rodents.
Date: May 1972
Creator: Alcoze, Thomas M.
Partner: UNT Libraries

Evaluating the Habitat Requirements of the Golden Orb Mussel (Quadrula Aurea) for Conservation Purposes

Description: Many freshwater mussels are imperiled, due to a number of interrelated factors such as habitat alteration, degradation of water quality, and impoundments. The Golden Orb mussel (Quadrula aurea, I. Lea, 1859) is endemic to the state of Texas and is currently a candidate for the endangered species list, as the number of known populations has been declining in recent years. Little is currently known about Q. aurea aside from basic distribution data. This study is focused on evaluating a combination of macro-habitat and micro-habitat variables to determine their influence on the distribution and density of this species. Macro-habitat variables, including dominant land cover, surface geology, and soil erodibility factor, did not have a significant relationship with mussel distributions. The best model of micro-habitat variables that impacts the Q. aurea distributions is comprised of relative substrate stability (RSS) at moderate flows and current velocity at low flows. For all mussel species in this study, current velocity at low flows is the primary variable that influences distribution. Q. aurea are associated with habitats where larger sediment particles (large gravel and cobble) help to stabilize the substrate in areas with higher current velocities. An understanding of the preferred habitats for Q. aurea can be used to help focus conservation efforts and practices.
Date: May 2013
Creator: Hammontree, Sarah
Partner: UNT Libraries

Analysis of the One-Horned Rhinoceros (Rhinoceros Unicornis) Habitat in the Royal Chitwan National Park, Nepal.

Description: This study analyzes the remaining suitable habitat of the one-horned rhinoceros, Rhinoceros unicornis, in Royal Chitwan National Park of Nepal. An April 2003 Landsat image was classified into eight land cover types: wetland, sand, water, mixed forest, sal forest, agriculture, settlement, and grassland. This image was converted into habitat suitability maps using cover, food, and water. The rhinoceros prefers grassland habitat with oxbow lakes and closed canopy during the monsoon season. Nominal values of five parameters were used to create a map of habitat suitability index. The map was categorized into four habitat classes: highly unsuitable, unsuitable, moderately suitable habitat, and suitable. Landscape metrics, patch metrics and class metrics associated with habitat were determined through the use of FRAGSTATS.
Date: December 2005
Creator: Thapa, Vivek
Partner: UNT Libraries

Habitat-Lite: A GSC case study based on free text terms for environmental metadata

Description: There is an urgent need to capture metadata on the rapidly growing number of genomic, metagenomic and related sequences, such as 16S ribosomal genes. This need is a major focus within the Genomic Standards Consortium (GSC), and Habitat is a key metadata descriptor in the proposed 'Minimum Information about a Genome Sequence' (MIGS) specification. The goal of the work described here is to provide a light-weight, easy-to-use (small) set of terms ('Habitat-Lite') that captures high-level information about habitat while preserving a mapping to the recently launched Environment Ontology (EnvO). Our motivation for building Habitat-Lite is to meet the needs of multiple users, such as annotators curating these data, database providers hosting the data, and biologists and bioinformaticians alike who need to search and employ such data in comparative analyses. Here, we report a case study based on semi-automated identification of terms from GenBank and GOLD. We estimate that the terms in the initial version of Habitat-Lite would provide useful labels for over 60% of the kinds of information found in the GenBank isolation-source field, and around 85% of the terms in the GOLD habitat field. We present a revised version of Habitat-Lite and invite the community's feedback on its further development in order to provide a minimum list of terms to capture high-level habitat information and to provide classification bins needed for future studies.
Date: April 1, 2008
Creator: Kyrpides, Nikos; Hirschman, Lynette; Clark, Cheryl; Cohen, K. Bretonnel; Mardis, Scott; Luciano, Joanne et al.
Partner: UNT Libraries Government Documents Department

A determination of the spatial concordance between Lyme disease incidence and habitat probability of its primary vector Ixodes scapularis (black-legged tick)

Description: This article involves mapping the probability of occurrence that the disease vector exists in the environment, mapping the incidence of Lyme disease in the human population and examining the spatial concordance between the probability map and incidence map.
Date: November 1, 2014
Creator: Atkinson, Samuel F.; Sarkar, Sahotra; Avina, Aldo; Schuermann, Jim A. & Williamson, Phillip C.
Partner: UNT College of Arts and Sciences

Microbial co-habitation and lateral gene transfer: what transposases can tell us

Description: Determining the habitat range for various microbes is not a simple, straightforward matter, as habitats interlace, microbes move between habitats, and microbial communities change over time. In this study, we explore an approach using the history of lateral gene transfer recorded in microbial genomes to begin to answer two key questions: where have you been and who have you been with? All currently sequenced microbial genomes were surveyed to identify pairs of taxa that share a transposase that is likely to have been acquired through lateral gene transfer. A microbial interaction network including almost 800 organisms was then derived from these connections. Although the majority of the connections are between closely related organisms with the same or overlapping habitat assignments, numerous examples were found of cross-habitat and cross-phylum connections. We present a large-scale study of the distributions of transposases across phylogeny and habitat, and find a significant correlation between habitat and transposase connections. We observed cases where phylogenetic boundaries are traversed, especially when organisms share habitats; this suggests that the potential exists for genetic material to move laterally between diverse groups via bridging connections. The results presented here also suggest that the complex dynamics of microbial ecology may be traceable in the microbial genomes.
Date: March 1, 2009
Creator: Hooper, Sean D.; Mavromatis, Konstantinos & Kyrpides, Nikos C.
Partner: UNT Libraries Government Documents Department

Protocols for Monitoring Habitat Restoration Projects in the Lower Columbia River and Estuary

Description: Protocols for monitoring salmon habitat restoration projects are essential for the U.S. Army Corps of Engineers' environmental efforts in the Columbia River estuary. This manual provides state-of-the science data collection and analysis methods for landscape features, water quality, and fish species composition, among others.
Date: April 25, 2008
Creator: Roegner, G. Curtis; Diefenderfer, Heida L.; Borde, Amy B.; Thom, Ronald M.; Dawley, Earl M.; Whiting, Allan H. et al.
Partner: UNT Libraries Government Documents Department

Idaho Fish Screening Improvements Final Status Report.

Description: This project funds two Idaho Department of Fish and Game (IDFG) fish habitat biologists to develop, secure funding for, and implement on-the-ground fish habitat improvement projects in the lower Clearwater River drainage and the upper Salmon River drainage. This report summarizes project activity during the first year of funding. The Clearwater Region fish habitat biologist began work on January 28, 2008 and the Salmon Region habitat biologist began on February 11, 2008.
Date: November 12, 2008
Creator: Leitzinger, Eric J.
Partner: UNT Libraries Government Documents Department

Post-Hurricane Assessment of Sensitive Habitats of the Flower Garden Banks Vicinity

Description: This report evaluates the damage cause by Hurricane Rita to the benthic habitats of four banks: Sonnier, McGrail, Geyer, and Bright. They measured the damage to bank caps the community structure, and used SCUBA to video record the evidence.
Date: July 2009
Creator: Robbart, Martha L.; Aronson, Richard B.; Deslarzes, Kenneth J.P.; Precht, William F.; Duncan, Leslie; Zimmer, Beth et al.
Partner: UNT Libraries Government Documents Department

NOAA Fiscal Year 2014 Budget Summary

Description: This report discusses the fiscal year 2014 which aims for NOAA to focus on credible science, healthy oceans, sustainable seafood and jobs, and climate information and decision support.
Date: unknown
Creator: United States. National Oceanic and Atmospheric Administration.
Partner: UNT Libraries Government Documents Department

International Standards fir the Practice if Ecological Restoration- Including Principles and Key Concepts

Description: A document that provides standards to guide practitioners, operational personnel, planners, managers, regulators, and funding agencies involved in restoring degraded ecosystems anywhere in the world- whether terrestrial, freshwater, coastal or marine.
Date: 2016
Creator: McDonald, Tein; Gann, George D.; Jonson, Justin & Dixon, Kingsley W.
Partner: UNT Libraries Government Documents Department

An Ecological Study of the Pine Vole, Microtus Pinetorum, in Northeast Texas

Description: This study dealt with the life history and population dynamics of the pine vole, Microtus pinetorum. In the past there has been a void of ecological material concerning this small mammal in the southwestern region of its range. From November, 1969, through February, 1970, a survey was conducted in Marion County and Harrison County, Texas, to determine the most suitable habitat for an ecological study of Microtus pinetorum. A study was then initiated in March, 1970, and continued through March, 1971, on an undisturbed marsh five miles south of Marshall, Harrison County, Texas.
Date: August 1971
Creator: Greer, Roy E.
Partner: UNT Libraries