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Book An Assessment of Sea Turtle Nesting Behavior in Relation to Hurricane and Restoration induced Beach Morphodynamics

Download or read book An Assessment of Sea Turtle Nesting Behavior in Relation to Hurricane and Restoration induced Beach Morphodynamics written by Tonya Michele Long and published by . This book was released on 2010 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coastal habitats are highly dynamic and vulnerable to landscape-level disturbances such as storms and restoration projects. Along the east coast of Florida these areas are particularly valuable as they provide significant nesting habitat for two sea turtle species, the threatened loggerhead (Caretta caretta) and the endangered green turtle (Chelonia mydas). This coast was heavily impacted by three major hurricanes in 2004 and in some areas by large restoration projects in 2005. Recent remote sensing methods allow for broad evaluation of the shoreline and thus the ability to assess sea turtle nesting habitat at a landscape scale. I collected nesting data for southern Brevard County, Florida from 1989-2005 and for Canaveral National Seashore, Florida from 1995-2005. I used LiDAR (Light Detection and Ranging) and IfSAR (Interferometric Synthetic Aperture Radar) remote sensing to map sea turtle nesting habitat in both areas following the 2004 hurricanes and any subsequent restoration. Canaveral National Seashore underwent no restoration while southern Brevard County received extensive restoration. Topographic variables (e.g., total sand volume, width, and slope) derived from the remote sensing data were compared across three time periods (pre-hurricane, post-hurricane, and recovery period) and I compared nesting success data from 2004 to 2005. I built regression models for 2004 and 2005 to determine which topographic features influenced loggerhead and green turtle nesting the most. Green turtle nesting success declined from 2004 to 2005 only in highly restored areas while loggerhead nesting sucess declined throughout. Hurricanes caused a reduction in most of the topographic variables and restoration predominantly impacted aspects of the beach profile (e.g. slope and width). Loggerheads responded to profile characteristics (e.g. upper and lower beach slopes) though green turtles showed no consistent response to topography. The results indicate that both loggerheads and green turtles are sensitive to beach restoration, although loggerhead nesting is more influenced by beach morphology and green turtle nesting may be influenced more by other dune features such as vegetation cover.

Book Response of Nesting Sea Turtles to Tilling of Compacted Beaches Jupiter Island Florida

Download or read book Response of Nesting Sea Turtles to Tilling of Compacted Beaches Jupiter Island Florida written by David Arthur Nelson and published by . This book was released on 1988 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to examine nest establishment and hatching success of nests of sea turtles in a compacted, nourished beach which has been tilled to decrease sand compaction. This study demonstrates the effectiveness of tilling at a full scale commercial level and the response of nesting turtles to the tilled beach.

Book Recovery Plan for Marine Turtles

Download or read book Recovery Plan for Marine Turtles written by Sally R. Hopkins and published by . This book was released on 1984 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Quantitative Tools for Monitoring Strategy Evaluation and Assessment of Sea Turtle Populations

Download or read book Quantitative Tools for Monitoring Strategy Evaluation and Assessment of Sea Turtle Populations written by Susan E. H. Piacenza and published by . This book was released on 2016 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Green sea turtles, Chelonia mydas, have endangered and threatened populations globally, but several populations show signs of population recovery. In Hawaii, nesting female green turtles have increased 5.7% year−1 since 1973, but wide fluctuations in census counts of nesting females make recovery diagnosis difficult. For effective management planning, it is critical to have the best information possible on vital rates, and to determine the best tools and practices for incorporating vital rate information, particularly variability, into population models to assess population size and status. Process and observation errors, compounded by late maturity, obscure the relationship between trends on the nesting beach and the entire population. Using sea turtle nesting beach surveys as a population index for assessment is problematic, yet often pragmatic because this is the only population index that is easily accessible. It is advantageous to use a modelling approach that estimates interannual variability in life history traits, accounts for uncertainty from individual-level variability, and allows for population dynamics to emerge from individual behaviors. To this end, I analyzed a long-term data set of marked green sea turtles to determine the degree of temporal variability in key life history traits. From this analysis, I built an agent-based model (ABM) to form the basis of a new assessment tool -- Monitoring Strategy Evaluation. In Chapter 2, I evaluated annual changes in demographic indicators (DIs) of 3,677 nesting green turtles from a 38-year tagging program in the Hawaiian Islands to determine if key life history traits are changing over time and in response to nester density. I used linear mixed models and multistate open robust design models to estimate several DIs and correlated them with nesting female counts. Mean nester carapace length and breeding probability were highly variable over time, suggesting shifts in age structure that could be due to recruitment. The top-ranked model predicted constant female survival over time. A significant positive relationship between the nesting population and breeding probability was evident, and breeding probability shows promise as an indicator of population recovery. This work contributes to a growing set of studies evaluating sea turtle demography for temporal variability and is the first for Hawaiian green turtles. In Chapter 3, I develop the Green Sea Turtle Agent-Based Model (GSTABM) to evaluate how recovery processes differ across disturbance types. The GSTABM incorporates individually variable age-at-maturity, clutch frequency and clutch size, annually variable breeding probability, environmental stochasticity and density dependence in hatchling production. The GSTABM simulates the process of population impact and recovery and the monitoring process, with observation error, on the nesting beach. The GSTABM captures the emergent patterns of interannual nesting variation, nester recruitment, and realistic population growth rates. Changes in survival rates of the nearshore age-stage classes directly affected adult and nester abundance, population growth rate and nester recruitment more than any of the other input parameters. In simulating 100 years of recovery, experimentally disturbed populations began to increase but did not fully return to pre-disturbance levels in adult and nester abundance, population growth or nester recruitment. In simulations with different levels of monitoring effort, adult abundance was poorly estimated, was influenced by population trajectory and disturbance type, and showed marginal improvements in accuracy with increased detection probability. Estimating recruitment showed improvements with increasing detection levels. In the GSTABM, variability in the nesting beach does not mirror variability in adult abundance. The GSTABM is an important tool to determine relationships with monitoring, population assessment, and the underlying biological processes driving changes in the population, and especially, changes on the nesting beach. In Chapter 4, I develop a new simulation-based tool: Monitoring Strategy Evaluation (MoSE) to determine which data source yields the most useful information for population assessments. The MoSE has three main components: the simulated "true" operating, observation, and estimation models. To explore this first use of MoSE, I apply different treatments of disturbance, sampling, and detection to the virtual "true" population, and then sample the nests or nesters, with observation error, to test if the observation "data" accurately diagnose population status indicators. Based on the observed data, I estimated adult abundance, nester recruitment, and population trend and compare them to the known values. I tested the accuracy of the estimated abundance when annually varying inputs of breeding probability, detection and clutch frequency were used instead of constants. I also explored the improvement of trend accuracy with increased study duration. Disturbance type and severity can have important and persistent effects on the accuracy of population assessments drawn from monitoring rookeries. Accuracy in abundance estimates may be most improved by avoiding clutch frequency bias in sampling and including annually varying inputs in the estimation model. Accuracy of nester recruitment may be most improved by increasing detection level and avoiding age-bias in sampling. The accuracy of estimating population trend is most influenced by the underlying population trajectory, disturbance type and disturbance severity. At least 10 years of monitoring data are necessary to accurately estimate population trend, and longer if juvenile age classes were disturbed and trend estimates occur during the recovery phase. The MoSE is an important tool for sea turtle biologists and conservation managers and allows biologists to make informed decisions regarding the best monitoring strategies to employ for sea turtles. This modeling framework is designed to provide an evaluation of monitoring program effectiveness to assist in planning future programs for sea turtles. Altogether, my research suggests certain life history traits of green sea turtles have important temporal variation that should be accounted for in population models, understanding the relationships between nesting and the total population is essential, and basing population assessments from nesting beach data alone is likely to result in incorrect or biased estimates of status indicators. The quantitative tools employed here can be applied to other sea turtle populations and will improve monitoring, and result in better estimates of current population trends and enhance conservation for all species of sea turtles.

Book The Effects of Beach Renourishment on the Nesting Behavior and Hatching Success of the Loggerhead Sea Turtle on Jupiter Island Florida

Download or read book The Effects of Beach Renourishment on the Nesting Behavior and Hatching Success of the Loggerhead Sea Turtle on Jupiter Island Florida written by Mary Julie Steinitz and published by . This book was released on 1996 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Oceanic Abstracts

Download or read book Oceanic Abstracts written by and published by . This book was released on 1996-10 with total page 1002 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Beach Restoration in Florida

Download or read book Beach Restoration in Florida written by Mario Jorge Mota and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High sand compaction restricts gas diffusion between clutch and atmosphere. This accumulates carbon dioxide in the clutch and prevents oxygen from reaching the eggs. This combination of gases is detrimental to sea turtle development and leads to lower hatching and emerging successes. In the second experiment I found that high concentrations of unbound sand calcium carbonate reduced clutch carbon dioxide concentrations during the second half of incubation. This buffering effect maintained incubation gases within safe physiological levels and reduced clutch mortality. However, hatchlings emerging from these nests had significantly smaller body depths, higher packed cell volumes, higher total protein levels, and higher triglycerides. This physiological data indicate these hatchlings were more dehydrated and metabolized more yolk than controls. Their physiological condition worsened after crawling 10 meters, intended to replicate traversing the beach to ocean. Data show that although clutch carbon dioxide levels can be reduced by unbound sand calcium carbonate, high sand compaction has a consistently negative impact on diffusion of oxygen and carbon dioxide molecules. Differences in atmospheric concentrations, diffusion rates, and solubility of oxygen and carbon dioxide molecules, intensify this effect for the latter. Regulation of specific sand characteristics is paramount for beach nourishment projects. Engineers and regulators should incorporate the information emanating from this dissertation into future beach restoration projects because it relates human needs to the consequences beach sand can have on the incubation of loggerhead sea turtles.

Book 1982 Sea Turtle Project

Download or read book 1982 Sea Turtle Project written by Jennifer D. McMurtray and published by . This book was released on 1982 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Papers Presented at the Expert Consultation on Interactions Between Sea Turtles and Fisheries Within an Ecosystem Context

Download or read book Papers Presented at the Expert Consultation on Interactions Between Sea Turtles and Fisheries Within an Ecosystem Context written by and published by Food & Agriculture Org.. This book was released on 2004 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: The original report published in 2004 (ISBN 925105542)