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- Title
- Developmental Morphology of Flippers in Sea Turtles and Penguins.
- Creator
- Kwong, Grace W., Wyneken, Jeanette, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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There are no modem anatomical studies of flipper development or particularly any examining limb formation across distantly related taxa converging on similar flipper morphology. This study compares and contrasts the development of flippers in sea turtle (Caretta caretta) and penguin (Spheniscus demersus , Eudyptula minor) embryos. Embryos were fixed, cleared and stained for cartilage anlagen, and prepared as whole mounts. Skeletal elements forming the flipper and changes in their growth rates...
Show moreThere are no modem anatomical studies of flipper development or particularly any examining limb formation across distantly related taxa converging on similar flipper morphology. This study compares and contrasts the development of flippers in sea turtle (Caretta caretta) and penguin (Spheniscus demersus , Eudyptula minor) embryos. Embryos were fixed, cleared and stained for cartilage anlagen, and prepared as whole mounts. Skeletal elements forming the flipper and changes in their growth rates were described across developmental stages. Results suggest skeletal elements contribute differently to sea turtle and penguin flipper blades and there are significant differences in bone shape and growth patterns. Greater proportional increases in lengths and areas were found in sea turtles elements compared to penguins. Sea turtles appear to depend on a pathway resulting in elongation of distal elements to build a flipper, whereas penguin limbs undergo flattening and expansion of fewer elements to meet a similar structural goal.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fau/fd/FA00000784
- Subject Headings
- Sea turtles--Physiology, Sea turtles--Morphology, Penguins--Morphology, Animal locomotion, Marine ecology
- Format
- Document (PDF)
- Title
- Feeding behavior of loggerhead and leatherback sea turtles:a study to better understand longline bycatch.
- Creator
- Warraich, Natasha, Wyneken, Jeanette, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Two species of sea turtle, loggerheads (Caretta caretta) and leatherbacks (Dermochelys coriacea) are caught frequently as bycatch in longline fisheries. These fisheries use hooks baited with fish or squid. Yet, leatherbacks feed on gelatinous prey while loggerheads are carnivores. I investigated the responses of these two species to bait odors in controlled laboratory experiments to better understand their feeding behavior and why they interact with longlines. Both species initiated feeding...
Show moreTwo species of sea turtle, loggerheads (Caretta caretta) and leatherbacks (Dermochelys coriacea) are caught frequently as bycatch in longline fisheries. These fisheries use hooks baited with fish or squid. Yet, leatherbacks feed on gelatinous prey while loggerheads are carnivores. I investigated the responses of these two species to bait odors in controlled laboratory experiments to better understand their feeding behavior and why they interact with longlines. Both species initiated feeding behavior in the presence of squid bait odors and just C. caretta showed feeding behavior with sardine odors; neither responded to mackerel odors. The turtles are hooked differently on longlines. Loggerheads are usually hooked in the mouth while leatherbacks are usually hooked in the shoulder or flippers. Comparisons of prey attack behavior and accuracy in apprehending a stimulus in the presence of waterborne food odors identified speciesspecific differences that may predispose the turtles to particular kinds of hooking.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004171, http://purl.flvc.org/fau/fd/FA00004171
- Subject Headings
- Bycatches (Fisheries) -- Prevention, Longlining (Fisheries) -- Bycatches -- Prevention, Longlining (Fisheries) -- Environmental aspects, Sea turtles -- Effect of fishing on, Sea turtles -- Habitat -- Conservation, Sea turtles -- Mortality, Wildlife conservation
- Format
- Document (PDF)
- Title
- Gopher tortoise habitat use and spatial distribution in a southeastern Florida population.
- Creator
- King, E. H., Florida Atlantic University, Wyneken, Jeanette, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Gopher tortoise ecology is poorly understood in the rapidly developing, urbanized southeastern end of its range. This study reports on a population at Florida Atlantic University in Boca Raton, Florida. Burrow surveys were conducted from May to July 2003 and May to August 2004. Burrows were marked and mapped as was vegetative cover. Burrow locations were tested against vegetative cover height and soil types. Burrow locations did not differ among soil types. The densest concentrations of...
Show moreGopher tortoise ecology is poorly understood in the rapidly developing, urbanized southeastern end of its range. This study reports on a population at Florida Atlantic University in Boca Raton, Florida. Burrow surveys were conducted from May to July 2003 and May to August 2004. Burrows were marked and mapped as was vegetative cover. Burrow locations were tested against vegetative cover height and soil types. Burrow locations did not differ among soil types. The densest concentrations of burrows were located in areas of low, patchy vegetative cover. This is consistent with known gopher tortoise habitat preferences elsewhere in their range. Gopher tortoises on this site appeared to be acclimated to anthropogenic disturbance.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/13272
- Subject Headings
- Ecology, Gopher tortoise--Geographical distribution, Habitat (Ecology)--Florida, Zoogeography
- Format
- Document (PDF)
- Title
- Identifying mating systems of imperiled marine turtles nesting in southern Florida through exclusion analysis to estimate the breeding sex ratio.
- Creator
- Lasala, Jacob A., Wyneken, Jeanette, Hughes, Colin, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The reproductive behavior of migratory organisms is difficult to characterize as the mating behavior can be difficult to observe. For some species, one sex can be readily observable, but the other may remain hidden, confounding attempts to assess population demographics. For such species, it can be difficult to determine the sex ratio of the population. Without accurate accounts of the numbers of males and females, conservation methods may be insufficient and their performance unclear....
Show moreThe reproductive behavior of migratory organisms is difficult to characterize as the mating behavior can be difficult to observe. For some species, one sex can be readily observable, but the other may remain hidden, confounding attempts to assess population demographics. For such species, it can be difficult to determine the sex ratio of the population. Without accurate accounts of the numbers of males and females, conservation methods may be insufficient and their performance unclear. Alternative methods of measuring sex ratios therefore must be used to estimate the number of individuals and assess breeding behavior. Here I identified breeding sex ratios (BSR) measured using paternity analysis of offspring through exclusion analysis to quantify the numbers of males contributing. Here I discuss the mating behavior of three species of marine turtle that nest in southern Florida: the loggerhead (Caretta caretta), the leatherback (Dermochelys coriacea), and the green sea turtle (Chelonia mydas) at three beaches (Boca Raton, Juno Beach, and Sanibel Island) from 2013-2017; over 400 nesting females were identified and genotyped and almost 7,000 hatchlings were collected and genotyped. Females from all three species successfully mated with more than one male in all years analyzed demonstrating multiple paternity of clutches. For loggerheads, many male genotypes were identified, suggesting that females likely mate en route to their nesting grounds, inducing a male-biased BSR. Examination of females that were sampled more than once per season (repeats), evidence of sperm storage was found for all nests and some turtles might mate in between nesting events. Leatherback females displayed a higher rate of multiple paternity than was previously published for other Caribbean nesting sites; I hypothesize that this result may be due to a mainland nesting beach effect. The leatherback BSR over all years was approximately 1:1, and one male was identified fathering than two different females’ nests (polygyny). For green turtles, multiple paternity was found and there was evidence of polygyny. Across all three species, evidence for indirect benefits of mating multiply (hatching success or larger hatchlings) was weak or not supported. Together, the four studies contribute to the overall body of reproductive behavior studies.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FA00013161
- Subject Headings
- Sea turtles--Florida, Mating behavior, Sex ratio
- Format
- Document (PDF)
- Title
- Measuring Nest-to-Surf Mortality of Florida’s East and West Coast Loggerhead Sea Turtle (Caretta caretta) Hatchlings.
- Creator
- Villegas Vindiola, Brianna, Wyneken, Jeanette, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Sea turtle hatchlings emerge from their nest and quickly crawl to the surf. During the crawl, hatchlings may encounter threats, biotic and abiotic, which can affect their ability to successfully reach the surf. The impact of these threats on hatchling survival during that crawl is largely undocumented. Current methods used to estimate cohort recruitment rely heavily on nest inventory data. This method, however, does not account for post-emergent hatchling mortality that occurs during the...
Show moreSea turtle hatchlings emerge from their nest and quickly crawl to the surf. During the crawl, hatchlings may encounter threats, biotic and abiotic, which can affect their ability to successfully reach the surf. The impact of these threats on hatchling survival during that crawl is largely undocumented. Current methods used to estimate cohort recruitment rely heavily on nest inventory data. This method, however, does not account for post-emergent hatchling mortality that occurs during the crawl. During the 2017-2018 nesting seasons, I quantified the fates of 1,379 loggerhead (Caretta caretta) hatchlings from 26 nest emergences during their crawl from the nest to the surf on the east and west coasts of Florida. I documented hatchling fates at 5 Florida nesting beaches: Wabasso, Boca Raton, Keewaydin Island, Naples, and Anna Maria Island. Overall, 6.5% of all emergent hatchlings died during the crawl from the nests to the surf. Ghost crabs, night herons, foxes, and coyotes killed hatchlings and photopollution and barriers on the beach (both abiotic threats) caused hatchling mortality. Anthropogenic (abiotic) threats accounted for more mortality than did predators. In order to assess how beach urbanization impacts hatchling mortality, I categorized each study site as urban (Wabasso and Naples), intermediate (Anna Maria Island and Boca Raton), or natural (Keewaydin Island) based on the relative levels of shoreline development and human activity at each beach. Sites with intermediate levels of urbanization accounted for greater levels of hatchling mortality than at other beaches due to the absolutely larger numbers of hatchlings lost to a disorientation event and to a beach barrier. Given the small numbers of emergences, at all sites, only a small proportion of the hatchlings mortalities (e.g., between 3 and 12 percent), site type could not be rigorously used as a discriminator. My results provide a better understanding of how specific environmental threats contribute to hatchling mortality. While nest-to-surf mortality is relatively low, its cumulative costs add up to several hundreds of thousands of hatchlings. Armed with this information, nesting beach managers can assess risks and focus their efforts to implement the most effective management practices to minimize losses of this imperiled species.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013277
- Subject Headings
- Loggerhead turtle--Florida, Caretta caretta, Sea turtles--Nests, Sea turtles--Mortality
- Format
- Document (PDF)
- Title
- MULTIPLE ENVIRONMENTAL FACTORS PRODUCE HIGH HATCHING AND EMERGENCE SUCCESS IN NORTHWEST ATLANTIC LOGGERHEADS (CARETTA CARETTA).
- Creator
- Gravelle, Jessica, Wyneken, Jeanette, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Sea turtle nest success, defined as the number of eggs in a nest that successfully hatch and emerge, is closely linked to environmental conditions. Interacting biotic and abiotic factors influence hatching and hatchling emergence success. To date, combinations of multiple factors interacting together, which result in highly successful sea turtle nests are not well understood. Using 25-years of historic nest data and local expert experience, I identified five historically successful loggerhead...
Show moreSea turtle nest success, defined as the number of eggs in a nest that successfully hatch and emerge, is closely linked to environmental conditions. Interacting biotic and abiotic factors influence hatching and hatchling emergence success. To date, combinations of multiple factors interacting together, which result in highly successful sea turtle nests are not well understood. Using 25-years of historic nest data and local expert experience, I identified five historically successful loggerhead (Caretta caretta) nesting beaches (hotspots) along the Florida (USA) Atlantic coast and measured nest environments along with nest success. Principal component analysis was used to reduce 12 environmental variables so that the relative contributions of sand characteristics, nest temperature, sand moisture, and nest location were considered. The nest environments differed among nesting beaches and were broadly segregated into two distinct climates: subtropical (hot and humid) and warm-temperate (warm and dry). I found that nests at subtropical sites, compared with the warm-temperate sites, were characterized by environmental gradients in contrasting ways. Nest locations were predominantly mid-beach in subtropical sites but clustered at higher elevations and closer to the base of the dune at warm-temperate climate sites. Collectively, highly successful nest hotspots represent a mosaic of abiotic factors providing conditions that promote successful hatching and emergence. This new perspective on consistently successful loggerhead nesting beach traits demonstrate that the key traits of sea turtle nesting habitat vary with prevailing climate type and should be managed accordingly.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013900
- Subject Headings
- Loggerhead turtle--Florida, Sea turtles--Nests, Caretta caretta, Sea turtles--Habitat--Conservation
- Format
- Document (PDF)
- Title
- Nest-to-surf mortality of loggerhead (Caretta caretta) sea turtle hatchlings on Florida’s east coast in 2016.
- Creator
- Erb, Victoria, Wyneken, Jeanette, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Worldwide, sea turtles are especially vulnerable immediately after emerging from nests. Many monitoring programs measure hatchling production from nest inventories. These inventories rarely account for mortality occurring post-emergence, leaving an incomplete estimate of hatchling production. This study addresses the nest-to-surf data gap for Florida’s east coast nesting assemblages of loggerhead sea turtles (Caretta caretta). Five locations were surveyed during the 2016 nesting season by...
Show moreWorldwide, sea turtles are especially vulnerable immediately after emerging from nests. Many monitoring programs measure hatchling production from nest inventories. These inventories rarely account for mortality occurring post-emergence, leaving an incomplete estimate of hatchling production. This study addresses the nest-to-surf data gap for Florida’s east coast nesting assemblages of loggerhead sea turtles (Caretta caretta). Five locations were surveyed during the 2016 nesting season by using infrared time-lapse imagery, night vision optics, and track maps. Over all beaches, 7.6% of the observed hatchlings did not survive to reach the water. Mortality sources varied by location. Observed predators included: foxes, bobcats, yellow-crowned night herons, ghost crabs, and gulls. Hatchling disorientation and misorientation occurred more frequently in urban areas than natural areas. Factors including number of hatchlings emerging, nest-to-surf distance, and urbanization may help managers estimate nest-to-surf mortality. This study will improve life history models that serve as foundations of conservation management.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004934, http://purl.flvc.org/fau/fd/FA00004934
- Subject Headings
- Sea turtles--Mortality--Florida., Loggerhead turtle--Mortality., Predation (Biology), Sea turtles--Orientation., Animal navigation., Fire ants--Venom--Physiological effect.
- Format
- Document (PDF)
- Title
- NESTING AND IN-WATER HABITAT-USE OF LOGGERHEAD SEA TURTLES (CARETTA CARETTA) AT A GLOBALLY IMPORTANT ROOKERY IN SOUTHEAST FLORIDA, USA.
- Creator
- Hirsch, Sarah, Wyneken, Jeanette, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Despite decades of conservation efforts, population recovery remains elusive for the loggerhead sea turtles (Caretta caretta) nesting in Florida, the largest aggregation globally. Limited studies exist regarding reproductive strategies and in-water habitat use of loggerheads in southeastern Florida. I used satellite telemetry to track the movements of 17 nesting loggerheads on Juno and Jupiter Beaches during the 2020 and 2021 nesting seasons. The majority of females displayed high nest-site...
Show moreDespite decades of conservation efforts, population recovery remains elusive for the loggerhead sea turtles (Caretta caretta) nesting in Florida, the largest aggregation globally. Limited studies exist regarding reproductive strategies and in-water habitat use of loggerheads in southeastern Florida. I used satellite telemetry to track the movements of 17 nesting loggerheads on Juno and Jupiter Beaches during the 2020 and 2021 nesting seasons. The majority of females displayed high nest-site fidelity. Inter-nesting intervals ranged from 10–19 days and were negatively correlated with water temperatures. Core inter-nesting areas ranged from 3.7–805.8 km2 and were located a mean 1.6 km from land. Mean clutch frequency was 5.9 nests/female, the highest reported for any loggerhead population worldwide. These findings suggest the number of females in the southeastern Florida population may be over-estimated due to an underestimated clutch frequency. Protective measures should target high-use coastal areas to maximize conservation benefits.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013882
- Subject Headings
- Loggerhead sea turtles, Loggerhead turtle--Florida, Turtles--Conservation, Biotelemetry
- Format
- Document (PDF)
- Title
- Predicting leatherback sea turtle sex ratios using spatial interpolation of nesting beach temperatures.
- Creator
- Weston, Emily G., Wyneken, Jeanette, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Sex determination in leatherback sea turtles is directed primarily by the temperatures a clutch experiences during the middle third of development. Warmer temperatures tend to produce females will cooler temperatures yield males. Nest temperatures can vary spatially and temporally. During the 2010 and 2011 nesting seasons, this study estimated the hatchling sex ratio of leatherback sea turtles on Sandy Point National Wildlife Refuge (SPNWR), St. Croix, U.S. Virgin Islands. I measured sand...
Show moreSex determination in leatherback sea turtles is directed primarily by the temperatures a clutch experiences during the middle third of development. Warmer temperatures tend to produce females will cooler temperatures yield males. Nest temperatures can vary spatially and temporally. During the 2010 and 2011 nesting seasons, this study estimated the hatchling sex ratio of leatherback sea turtles on Sandy Point National Wildlife Refuge (SPNWR), St. Croix, U.S. Virgin Islands. I measured sand temperatures from May- August and across the spatial range of leatherback nesting habitat. I spatially interpolated those temperatures to create maps that predicted temperatures for all nests incubating on SPWNR. Nest temperatures were also directly measured and compared with predicted nest temperatures to validate the prediction model. Sexes of dead-in-nest hatchlings and full term embryos were used to confirm the sex-temperature response. The model showed that microclimatic variation likely impacts the production of both sexes on SPNWR.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004071
- Subject Headings
- Leatherback turtle -- Habitat -- St. Croix -- Sandy Point National Wildlife Refuge (United States Virgin Islands), Loggerhead turtle -- Effect of temperature on, Sandy Point National Wildlife Refuge (United States Virgin Islands), Sea turtles -- Nests -- St. Croix -- Sandy Point National Wildlife Refuge (United States Virgin Islands), Sex determination, Genetic, Sex ratios, Vegetation dynamics
- Format
- Document (PDF)
- Title
- Spatial and temporal distributions of sea turtles within the Florida current and surrounding waters.
- Creator
- Bovery, Caitlin M., Wyneken, Jeanette, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to their migratory nature and use of large current systems. Concentrations of animals can shift because turtles undergo large-scale migrations and habitat shifts seasonally as well as a function of lifestage. Surface counts of marine turtles in waters off Florida’s east coast were made in and adjacent to the Florida Current using standard aerial surveys....
Show moreAssessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to their migratory nature and use of large current systems. Concentrations of animals can shift because turtles undergo large-scale migrations and habitat shifts seasonally as well as a function of lifestage. Surface counts of marine turtles in waters off Florida’s east coast were made in and adjacent to the Florida Current using standard aerial surveys. While it is understood that marine turtles use waters off the eastern coast of Florida, here we document the magnitude of the shift in turtle presence each season throughout a two year study and identify habitat characteristics where turtles occur most frequently. Our assessment of marine turtles in the waters off southeast Florida provide valuable metrics describing the in-water biology of sea turtles in this area to inform future management strategies of these endangered species.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004083, http://purl.flvc.org/fau/fd/FA00004083
- Subject Headings
- Sea turtles -- Atlantic Coast (U.S.) -- Florida -- Distribution, Sea turtles -- Atlantic Coast (U.S.) -- Florida -- Geographical distribution
- Format
- Document (PDF)
- Title
- THE IMPACT OF ENVIRONMENTAL FACTORS ON LOGGERHEAD SEA TURTLE (CARETTA CARETTA) HATCHLING BIOLOGY.
- Creator
- Lolavar, Alexandra A., Wyneken, Jeanette, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The eggs of all sea turtle species develop in underground nests on oceanic nesting beaches. Eggs are unattended and their incubation conditions are subject to effects of the environment. Nest temperature influences various aspects of hatchling biology, including sex determination. Past studies identified that sea turtle embryos have a warm female cool male response pattern and rainfall has been thought to cool nest temperature. The effects of rainfall or periods of drought were often inferred...
Show moreThe eggs of all sea turtle species develop in underground nests on oceanic nesting beaches. Eggs are unattended and their incubation conditions are subject to effects of the environment. Nest temperature influences various aspects of hatchling biology, including sex determination. Past studies identified that sea turtle embryos have a warm female cool male response pattern and rainfall has been thought to cool nest temperature. The effects of rainfall or periods of drought were often inferred but not verified. Using laboratory and field studies, I examined how changes in environmental factors during incubation, particularly sand moisture, can affect nest conditions and hatchling biology. I derived temperature-sex ratio response curves for eggs incubated at different moisture levels to determine the effect of moisture on how embryos respond to temperature. I also studied how increasing moisture levels in relocated nests through daily watering influence nest conditions and discuss if this method is an effective mitigation strategy for the detrimental effects of increasing temperatures on embryo survival and sex ratios. I investigated how environmental factors, nest conditions, and hatchling biology can differ among sites on a nesting beach. Extreme moisture conditions, both low and high, result in a narrower transition between one sex ratio bias to another. I demonstrated that watering nests decreases nest temperatures and increases hatching success but watering has a minimal impact on sex ratios. Ambient beach conditions vary slightly in air temperature, rainfall, solar radiation, and humidity, depending on beach location. Nest conditions such as nest temperature and moisture also differ, but hatching success and sex ratios do not vary among different sites on the same nesting beach in Boca Raton, Florida. Ultimately, these studies together help identify and demonstrate how these environmental factors and drivers can affect the nest environment during incubation. Further developing our understanding of environmental factors, particularly nest moisture, and their variability will provide better predictions of future climate change effects and perhaps create more effective mitigation strategies.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013390
- Subject Headings
- Loggerhead turtle, Sea turtles--Nests, Environment, Eggs--Hatchability, Eggs--Incubation, Moisture
- Format
- Document (PDF)
- Title
- UNDERSTANDING THE PHENOTYPE: A STUDY ON HOW THE INCUBATION ENVIRONMENT INFLUENCES EMBRYO GROWTH, SEX, AND SEX RATIOS IN TURTLES WITH TEMPERATURE DEPENDENT SEX DETERMINATION.
- Creator
- Tezak, Boris M., Wyneken, Jeanette, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Currently, one of the most critical research priorities in wildlife science is to understand, describe, and predict how the unprecedented rate of climate change will impact organisms and ecosystems. This is particularly essential for thermally sensitive organisms that are already imperiled, such as turtles. For all known turtle species, the nest incubation environment plays a critical role in many developmental processes which can directly influence a number of phenotypic traits, such as body...
Show moreCurrently, one of the most critical research priorities in wildlife science is to understand, describe, and predict how the unprecedented rate of climate change will impact organisms and ecosystems. This is particularly essential for thermally sensitive organisms that are already imperiled, such as turtles. For all known turtle species, the nest incubation environment plays a critical role in many developmental processes which can directly influence a number of phenotypic traits, such as body size, mass, locomotor performance, behavior and even sex. Most chelonians (and all extant marine turtles) possess a mechanism known as temperature dependent sex determination (TSD), whereby gonads differentiate into ovaries or testes depending on the incubation temperature of the eggs during a critical period of embryonic development. The rapid rate of climate change highlights the need for a clear understanding of how potential changes in the nest environment will affect turtle development and hatchling phenotype. However, it is poorly understood how different environmental factors interact with the embryo’s own genetic program to produce a specific phenotype. My thesis aims to (i) provide a better understanding of the complex relationship between the developing embryo and the nest environment and its effect on hatchling phenotype, and (ii) offer a solution to the difficulties associated with identifying primary sex ratios in turtle species with TSD.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013421
- Subject Headings
- Phenotype, Temperature-dependent sex determination, Turtles--Growth
- Format
- Document (PDF)