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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An empirical assessment of factors precluding recovery of sauger in the lower Yellowstone River movement, habitat use, exploitation, and entrainment /

Jaeger, Matthew Edward. January 2004 (has links) (PDF)
Thesis (M.S.)--Montana State University, 2004. / Title from PDF title page (viewed Jan. 6, 2005). Includes bibliographical references (p. 57-67).
2

The role of habitat quality in shaping evolutionary dynamics, population dynamics, and conservation planning /

Hoekstra, Jonathan M. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 119-134).
3

Recovery from and effects of a catastrophic flood and debris flow on the brook trout (Salvelinus fontinalis) population and instream habitat of the Staunton River, Shenandoah National Park, Virginia

Roghair, Craig N., January 2000 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 2000. / Title from PDF title page (viewed on Apr. 3, 2005). Vita. Includes bibliographical references (p. 82-87).
4

Influence of hull configuration and vessel propulsion systems on sea turtle shell injuries

Spurlock, Chad M. 02 July 2012 (has links)
Loggerhead sea turtles in coastal waters often sustain injuries from vessel impacts. The influences of vessel hull configuration and propulsion system type on the incidence and severity of wounds in turtle/vessel interaction were investigated. Full-scale field tests using two vessels with deep-vee hulls were performed. An artificial carapace with a sandwich composite design of a closed-cell polyurethane foam core with faces constructed of polyester resin infused with glass microspheres was developed. As a basis for comparison, a number of cold-stunned green turtle carcasses were also used in the field experiments. Two vessels, a 5.4 m boat with an inboard jet-drive engine and a 7.3 m boat with an outboard 4-bladed propeller, were operated at planing speed, 40 km/h. The field test results revealed similar patterns and severity of injuries between the synthetic turtles and the green turtle carcasses. Statistical analysis of the field test results indicated the influence of hull type alone on the severity of turtle damage was minimal, and none of the tests conducted using a jet drive engine resulted in injuries to the shell that would be considered lethal, regardless of the vessel hull type, speed, or the animal's depth in the water at impact. Conversely, injuries occurring as a result of propeller and/or skeg impact at planing speed were always classified as fatal. A finite element analysis of the artificial turtle was performed to determine the force at which a carapace fractures from hull impact alone. The results of the finite element analysis suggest that hull impacts of common recreational jet-propulsion vessels are unlikely to cause lethal carapace fractures in loggerhead sea turtles.
5

A habitat suitability model for Ricord's iguana in the Dominican Republic

Dine, James. January 2009 (has links)
Thesis (M.S.)--Indiana University, 2009. / Title from screen (viewed on August 27, 2009). Department of Geography, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Jan Ramer, Aniruddha Banergee, Jeffery Wilson. Includes vita. Includes bibliographical references (leaves 47-52).
6

Analysis of recovery-recapture data for little penguins

Sidhu, Leesa A., Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2007 (has links)
This thesis analyses yearly mark-recapture-recovery information collected over a 36- year period, from 1968 to 2003, for 23 686 flipper-banded Little Penguins Eudyptula minor of Phillip Island, in south-eastern Australia. Such a long-term data set is extremely rare for any species. Few studies of any animal have been able to model age dependence for the survival, recapture and recovery probabilities simultaneously. I successfully apply such a modelling scheme and obtain biologically realistic age structures for the parameters. I also provide illustrations of erroneous results that may arise when analyses fail to consider simultaneous age dependence, or fail to detect annual variations that may mask age dependence. I obtain a low survival estimate of 17% in the first year of life, increasing to 71% in the second year, and around 80% thereafter, and declining gradually after age nine years. First-year survival increases with number of chicks fledged per pair, increases with annual average fledging weight and decreases with mean laying date. An increase in first-year survival is associated with warmer sea surface temperatures in the summer and autumn of the previous year, which agrees with biological considerations. Irrespective of this inter-year variation, birds born early in the breeding season, relative to the rest of their cohort, have greatly enhanced first-year survival, when compared to birds born late in that season. Fledglings survive better in years in which the mean fledgling weight is higher, and fledglings of above average weight have a better chance of survival than their underweight counterparts. I next analyse seven years of recapture data from a separate experiment studying the effect of banding on adult Little Penguins. In the year following marking, the i survival probability of banded birds is 6% lower than that of unbanded birds, while in subsequent years the survival is 4% lower for banded birds. Band loss is negligible. Finally, I compare the survival estimates for Phillip Island with those obtained for a six-year study in New Zealand. While first-year survival is significantly higher for New Zealand, there is a marked decline over time, coinciding with an increase in population size.
7

Recovery measures for the state endangered American marten an internship with two Wisconsin natural resource agencies /

Harvey, Sarah Lynn. January 2004 (has links)
Thesis (M. En.)--Miami University, Institute of Environmental Sciences, 2004. / Title from first page of PDF document. Includes bibliographical references (p. 22-26).
8

The Nature of People's Perceptions of Wolves

Nobel, Laura Briana 01 January 2009 (has links)
European immigrants once regarded wolves as the "devil in disguise" (Lopez, 1978, p.40). With our growing awareness of other cultural perspectives and flourishing body of scientific knowledge with regard to wolves' behavior, our perceptions of wolves have become more complicated and nuanced. Our collective awareness of the environment in which we live also gathers complexity. I examine these issues in this study. Wolves are returning to Oregon. The arrival of wolf B-45 in 1999 heralded the beginning of the return of wild wolves to Oregon. More wolves are expected to cross the border as young sub-adults disperse from the growing population in Idaho. This study explores our perceptions of wolves using empirical, qualitative methodology. Running in parallel with this main goal, I also seek to understand how these perceptions relate on a larger scale to the ways we understand nature. In exploring these questions qualitatively, I seek to answer the following questions: (a) What ways can story play a role in defining people’s perceptions, in particular, of wolves? (b) What lessons can be learned to inform future ecological educators' work to communicate on this or other similarly complex topics? (c) What is the collective story that we can tell each other on the eve of wolves' presence in the Oregon landscape becoming an acknowledged reality once again? (d) Finally, how can what is learned inform future ecological educational programs regarding wolves in the state? This study explores the above questions. In considering people's perceptions, I attempt to examine whether the desires to exterminate wolves are really gone. Perhaps, as we learn more about the complex ways that wolves interact in the landscape and the various ways that humans react to the idea of wolves, we may recognize the greater complexities in the ways we inter-relate with them.
9

A Habitat Suitability Model for Ricord’s Iguana in the Dominican Republic

Dine, James 23 June 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The West Indian iguanas of the genus Cyclura are the most endangered group of lizards in the world (Burton & Bloxam, 2002). The Ricord’s iguana, Cyclura ricordii, is listed as critically endangered by the International Union for Conservation of Nature (IUCN) (Ramer, 2004). This species is endemic to the island of Hispaniola (Figure 1), and can only be found in limited geographic areas (Burton & Bloxam, 2002). The range of this species is estimated to be only 60% of historical levels, with most areas being affected by some level of disturbance (Ottenwalder, 1996). The most recent population estimation is between 2,000 and 4,000 individuals (Burton & Bloxam, 2002). Information on potentially suitable habitat can help the conservation efforts for Ricord’s iguana. However, intensive ground surveys are not always feasible or cost effective, and cannot easily provide continuous coverage over a large area. This paper presents results from a pilot study that evaluated variables extracted from satellite imagery and digitally mapped data layers to map the probability of suitable Ricord’s iguana habitat. Bayesian methods were used to determine the probability that each pixel in the study areas is suitable habitat for Ricord’s iguanas by evaluating relevant environmental attributes. This model predicts the probability that an area is suitable habitat based on the values of the environmental attributes including landscape biophysical characteristics, terrain data, and bioclimatic variables.

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