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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.
181

Effects Of A Shore Protection Project On Loggerhead And Green Turtle Nesting Activity And Reproduction In Brevard County, Florida

Brock, Kelly 01 January 2005 (has links)
Marine turtle reproductive success is strongly correlated with the stability and quality of the nesting environment. Because females show fidelity to key nesting beaches, the management and physical characteristics of these beaches directly affect future generations of marine turtles and may be essential for the recovery of these threatened and endangered species. The impacts of beach restoration on loggerhead turtles (Caretta caretta) and on green turtles (Chelonia mydas) were investigated. Previous studies concerning beach nourishment projects have focused on loggerhead turtles. I compared data between nourished and non-nourished areas and between loggerhead and green turtles. I found, at one season post-nourishment, negative effects on nesting success and no significant effect on reproductive success for both loggerheads and established the same relationships with green turtles. Physical attributes of the fill sand, which did not facilitate acute scarp formation or severe compaction, did not physically impede turtles in their attempts to nest. Instead, the decrease in nesting success was attributed to an absence of abiotic and or biotic factors that cue nesting behavior. The increase in loggerhead nesting success rates during the second season post-nourishment was attributed to the equilibration process of the seaward crest of the berm. After the beach was restored, both species of turtles placed nests significantly farther from the water in the nourished area than in the non-nourished area. Green turtles nested on or near the dune and loggerheads nested on the seaward crest of the berm. The tendency of loggerheads to nest closer to the water resulted in more loggerhead than green turtle nests being "washed out" by erosion during the equilibration process. There was a significant increase in hatching success only for loggerheads when wash outs were excluded, thus illustrating the importance of nest placement and the detrimental effects of the equilibration process to the reproductive success of loggerheads. A decrease in reproductive output occurred during the first season post-nourishment. The reduction in the estimated total number of hatchlings produced (reproductive output) was a consequence of decreased nesting success lowering nest numbers. This reduction demonstrates that, regardless of similar reproductive success rates, marine turtles incurred net losses during the first season following nourishment. These results further reveal the impacts of decreased nesting success and the importance of minimizing excessive non-nesting emergences associated with beach nourishment.
182

Factors Affecting Predation Of Marine Turtle Eggs By Raccoons And Ghost Crabs On Canaveral National Seashore, Fl

Brown, Justin 01 January 2009 (has links)
Changes in abundance of interactive species can have cascading, community-wide effects (Soule et al. 2003). Raccoons (Procyon lotor) prey on a competitor for marine turtle eggs, the Atlantic ghost crab (Ocypode quadrata). Conservation of marine turtles often includes managing raccoons-the most obvious egg predator-which may have broader ecological effects, and unknown effects on egg predation. Neither the relationship between raccoons and ghost crab density nor the effects of ghost crab density on egg predation are well understood. I studied raccoon-ghost crab interactions and the effects of environmental variation on their activity during the 2007 marine turtle nesting season on Canaveral National Seashore, FL. My goal was to model predator activity and identify efficient management strategies to reduce egg predation. Raccoon activity increased with increasing habitat diversity and edge of the dominant cover type, coastal strand. Raccoon activity increased locally and became less variable near segments of beach accessed for human recreation, but activity was greater on undeveloped beach, where habitat diversity and edge were greater. Ghost crab density and size were primarily affected by sand characteristics and recreation but decreased with increasing raccoon activity in June, which may have contributed to sustained declines in ghost crab density. Hatching success of marine turtles decreased with increasing ghost crab egg predation, suggesting ghost crabs are an important cause of egg mortality and not merely scavengers on unhatched eggs. Egg predation by ghost crabs was unrelated to ghost crab density or size, likely a result of monitoring limitations, but raccoon activity increased with increasing egg predation by ghost crabs, supporting previous research and experimental evidence suggesting ghost crabs can facilitate secondary nest predation by raccoons. This indirect interaction has strong implications for marine turtle conservation, because its strength may increase with increasing ghost crab density, potentially negating the effects of raccoon removal.
183

The Effects of Subcortical Brain Damage on Hoarding, Nest Building, and Avoidance Behaviour in the Rat

Bentley, Jo-Ann Linda January 1967 (has links)
A review of anatomical and behavioural studies of the limbic system suggests that some structures which Papaz proposed as the central mechanism of emotion might be involved in food hoarding behaviour. Various structures in Papez· circuit were destroyed surgically and observations were taken on subsequent changes in food hoarding behaviour. In addition, observations were made on nest building behavior and on avoidance performance. It was found that rats with bilateral damage to the mammillothalamic tract and mammillary body were severely depressed in hoarding and avoidance behaviour. Septal damage caused a less severe deficit in both behaviours while hippocampal, domical or thalamic damage did not have a significant effect. A pilot study of hoarding behaviour in the hamster was carried out. / Thesis / Master of Arts (MA)
184

Abiotic Differences Between Green Turtle (chelonia Mydas) Nests In Natural Beach And Engineered Dunes: Effects On Hatching Success

Balfour, Martha 01 January 2010 (has links)
Habitat loss is among the biggest threats to conservation worldwide, so habitat restoration plays an increasing role in endangered species management. This is especially true for species with high site fidelity, such as nesting marine turtles. Sand replenishment is commonly used to restore coastal beaches after severe erosion events, and may affect marine turtles and other species that live or reproduce in that habitat. I investigated how abiotic characteristics of sand used in a dune restoration project at Archie Carr National Wildlife Refuge, Florida, affected reproduction of the federally-endangered green turtle (Chelonia mydas). Sand structure and composition can affect egg development and hatching success by altering nest conditions, with nests in fine-grain or very coarse sand suffering decreased hatching success. I determined that calcium carbonate content (27.0% ± 1.4 SE vs. 15.1% ± 3.8 SE), moisture content (3.29% ± 0.26 SE vs. 4.59% ± 0.25 SE), and grain size (427.53 µm ± 14.1 SE vs. 274.66 µm ± 29.1 SE) differed significantly between natural and restored dunes. Hatching success of green turtles (44.7% ± 6.2 SE vs. 65.8% ± 5.3 SE) was significantly lower on restored dunes compared to natural dunes with an estimated loss of 22,646 hatched eggs. Hatching success also decreased as the nesting season progressed. These results demonstrate the importance of regulating fill material used in beach restoration projects; substrate characteristics are easily evaluated and can significantly influence marine turtle hatching success.
185

Implications of Stand Adjacency and Edge for Birds in a Managed Forest Ecosystem

Foggia, Jennifer Rose 11 December 2015 (has links)
Managed forest ecosystems contribute to conservation of wildlife, and generally yield heterogeneous landscapes with patches that support different sessile organisms. Edges or boundaries between adjacent forest patches are often ecologically distinct from patch interiors and can have direct influences on community dynamics and ecosystem functioning near them. To quantify effects of edge and adjacent habitat conditions on avian metrics, I used a hierarchical multi-species occupancy model that considered individual species resource requirements to estimate community occupancy patterns, and used artificial nest surveys to model daily nest survival (DNS) using a Bayesian framework. Results indicated that adjacent forest conditions influenced bird population dynamics in focal forest stands, provided little evidence of an edge effect on avian community response patterns, and showed highest DNS in newly established forest stands. My results highlight the importance of considering type and spatial arrangement of different habitat patches for habitat planning operations on managed forest landscapes.
186

Effect of PCB 47/77 on Maternal Care Behavior and Associated Genes

Dover, Ellen Nicole 23 June 2011 (has links)
No description available.
187

Post-Parenthood Redefined: Race, Class, and Family Structure Differences

Feldman, Karie Ellen 30 July 2010 (has links)
No description available.
188

The Role of Exotic Shrubs in Determining Nesting Success of Hooded Warblers

Garrett, Daniel Roy January 2015 (has links)
No description available.
189

AN ANALYSIS OF ACOUSTIC COMMUNICATION WITHIN THE SOCIAL SYSTEM OF DOWNY WOODPECKERS (PICOIDES PUBESCENS)

Dodenhoff, Danielle J. 18 October 2002 (has links)
No description available.
190

Exploring factors affecting smallmouth bass nest success and reproductive behavior

Steinhart, Geoffrey B. 30 March 2004 (has links)
No description available.

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