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- Title
- A seasonal and latitudinal assessment of early growth rates in northern and southeastern loggerhead sea turtles (Caretta caretta L.).
- Creator
- Stokes, Lesley., Florida Atlantic University, Wyneken, Jeanette
- Abstract/Description
-
To improve our understanding of loggerhead life history, particularly factors affecting the duration of each age class and survivorship, detailed growth data must be interpreted. The purpose of this study was to investigate how temporal and spatial nest origin influence initial hatchling size and growth potential. Seasonal environmental fluctuations and maternal resource allocation could result in differential hatchling size and development. Hatchlings from ten sites from North Carolina to...
Show moreTo improve our understanding of loggerhead life history, particularly factors affecting the duration of each age class and survivorship, detailed growth data must be interpreted. The purpose of this study was to investigate how temporal and spatial nest origin influence initial hatchling size and growth potential. Seasonal environmental fluctuations and maternal resource allocation could result in differential hatchling size and development. Hatchlings from ten sites from North Carolina to Florida representing 2 subpopulations were sampled during 3 phases of the season. The largest (WT, SCL and SCW) hatchlings came from the northernmost site with initial size decreasing as latitude decreased. Turtles deposited during the earliest phase of the nesting season grew faster than those from later phases of the season. Differences in initial size and growth potential could influence early stage survivorship as a function of size-based predation, and may imply the need for separate consideration when constructing population models.
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fcla/dt/13070
- Subject Headings
- Loggerhead turtle--Growth, Sea turtles
- Format
- Document (PDF)
- Title
- The effect of filtered roadway lighting on nesting by loggerhead sea turtles (Caretta caretta L.).
- Creator
- Pennell, Jeffrey P., Florida Atlantic University, Salmon, Michael, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
The purpose of this study was to determine if filtered street lighting affected the nesting behavior of loggerhead sea turtles ( Caretta caretta L.). My study site was a nesting beach at Carlin Park, Jupiter, Florida. During the 1999 nesting season, portions of the beach were either kept dark or were illuminated by four 70 W high-pressure sodium (HPS) streetlights, each housed in a cut-off fixture covered by an acrylic (model #2422) filter. These filters excluded all light wavelengths below...
Show moreThe purpose of this study was to determine if filtered street lighting affected the nesting behavior of loggerhead sea turtles ( Caretta caretta L.). My study site was a nesting beach at Carlin Park, Jupiter, Florida. During the 1999 nesting season, portions of the beach were either kept dark or were illuminated by four 70 W high-pressure sodium (HPS) streetlights, each housed in a cut-off fixture covered by an acrylic (model #2422) filter. These filters excluded all light wavelengths below 540 nm. The excluded wavelengths repel nesting females. Daily counts of nesting and non-nesting crawls were made. Data from the 1999 nesting season were compared to historical records of nesting at the site between 1990 and 1998. I found no evidence that filtered lights affected nesting densities, or the ratio of successful to unsuccessful crawls. These results suggest that at Carlin Park, the nesting behavior of loggerhead females is unaffected by exposure of the beach to filtered street lighting.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12720
- Subject Headings
- Loggerhead turtle, Sea turtles--Nests
- Format
- Document (PDF)
- Title
- A comparative approach to understanding sea turtle hatchling metabolism during emergence.
- Creator
- Redfearn, Erin Cherish., Florida Atlantic University, Wyneken, Jeanette
- Abstract/Description
-
Sea turtle nests were compared to determine the effects of nest depth on hatchling anaerobic metabolism in Juno Beach, Florida, USA. In situ nests of 3 species (Caretta caretta, Chelonia mydas and Dermochelys coriacea) were compared. Relocated loggerhead nests were studied under an experimental regime. Nest temperatures and oxygen concentrations were monitored. On the night of first emergence, blood samples were taken from hatchlings resting at the nest chamber bottom and sand surface, and...
Show moreSea turtle nests were compared to determine the effects of nest depth on hatchling anaerobic metabolism in Juno Beach, Florida, USA. In situ nests of 3 species (Caretta caretta, Chelonia mydas and Dermochelys coriacea) were compared. Relocated loggerhead nests were studied under an experimental regime. Nest temperatures and oxygen concentrations were monitored. On the night of first emergence, blood samples were taken from hatchlings resting at the nest chamber bottom and sand surface, and digging to the sand surface. Samples were analyzed for lactate concentrations. Blood lactate levels were high in hatchlings actively digging and low for those resting. Lactate levels differed among species and nest depths. Within in situ nests, actively digging green turtle hatchlings had the highest lactate, followed by loggerhead hatchlings and leatherbacks (lowest). Loggerhead hatchlings digging from deeper relocated nests had higher lactate than those digging from shallower depths.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/15770
- Subject Headings
- Sea turtles--Metabolism, Loggerhead turtle, Green turtle, Leatherback turtle
- Format
- Document (PDF)
- Title
- Using unmanned aerial vehicle (UAV) surveys and traditional methods to examine influences on loggerhead sea turtle (Caretta caretta) nest site selection.
- Creator
- Manestar, Summer, Briggs, Tiffany Roberts, Florida Atlantic University, Department of Geosciences, Charles E. Schmidt College of Science
- Abstract/Description
-
This study examined the environmental and anthropogenic factors that may influence loggerhead sea turtle nest site selection and how these factors vary between successful nesting attempts and false crawls on a high-density sea turtle nesting beach in Boca Raton, Florida. Beach morphology, sand texture, and nests’ proximity to artificial structures were measured using a combination of drone-based photogrammetry, traditional surveys with Real Time Kinematic Global Positioning System (RTK GPS),...
Show moreThis study examined the environmental and anthropogenic factors that may influence loggerhead sea turtle nest site selection and how these factors vary between successful nesting attempts and false crawls on a high-density sea turtle nesting beach in Boca Raton, Florida. Beach morphology, sand texture, and nests’ proximity to artificial structures were measured using a combination of drone-based photogrammetry, traditional surveys with Real Time Kinematic Global Positioning System (RTK GPS), and sediment granulometry. Proximity to dune crossover stairs was significantly different between nests and false crawls, and the probability of a false crawl occurring decreased as proximity to dune crossover stairs increased. The results of this study will provide researchers with a new tool for nest monitoring and a better understanding of the microhabitat cues that may influence loggerhead sea turtle nest site selection and aid in guiding beach and sea turtle management decisions.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014184
- Subject Headings
- Loggerhead sea turtles, Drone aircraft, Sea turtles--Nests, Geomorphology
- Format
- Document (PDF)
- Title
- Surveying Antibiotic Resistance of Gram-Negative Bacteria Isolated from Wild-Caught and Rehabilitated Green Sea Turtles (Chelonia mydas) and Loggerhead Sea Turtles (Caretta caretta) of Florida.
- Creator
- Cortes, Christina M., Milton, Sarah L., Florida Atlantic University, Department of Marine Science and Oceanography, Charles E. Schmidt College of Science
- Abstract/Description
-
Antibiotic resistance is a growing concern due to the improper use of antibiotics. Not only is antibiotic resistance increasingly occurring in human populations, but it appears to be spreading in wildlife populations too due to drug overuse and misuse in medicine, farming, and industrial settings, and the subsequent release into watersheds. This project examined the prevalence of antibiotic resistant bacteria in the hindgut microbiome of green (Chelonia mydas) (n=60) and loggerhead (Caretta...
Show moreAntibiotic resistance is a growing concern due to the improper use of antibiotics. Not only is antibiotic resistance increasingly occurring in human populations, but it appears to be spreading in wildlife populations too due to drug overuse and misuse in medicine, farming, and industrial settings, and the subsequent release into watersheds. This project examined the prevalence of antibiotic resistant bacteria in the hindgut microbiome of green (Chelonia mydas) (n=60) and loggerhead (Caretta caretta) (n=57) sea turtles. Hindgut swabs were cultured for gram negative bacteria and exposed to 6 antibiotics. 83.3% of samples were resistant or intermediately resistant to at least one antibiotic, and 27.7% of samples were resistant or intermediately resistant to three antibiotics. This study provides more information regarding the relationship between turtle characteristics and the presence of antibiotic resistance in the hindgut of Florida sea turtles, as well as examine the types of bacteria found in the hindgut.
Show less - Date Issued
- 2024
- PURL
- http://purl.flvc.org/fau/fd/FA00014489
- Subject Headings
- Green sea turtles, Loggerhead sea turtles, Sea turtles--Florida, Drug Resistance, Bacterial
- Format
- Document (PDF)
- Title
- Calcium requirement and growth in the hatchling loggerhead sea turtle (Caretta caretta L.).
- Creator
- Alexander, Jeanne Louise., Florida Atlantic University, Wyneken, Jeanette
- Abstract/Description
-
The calcium requirement in captive-raised hatchling loggerhead sea turtles (Caretta caretta) was investigated. Comparisons were made among turtles on 6 experimental diets and between captive and wild turtles. Diets consisted of trout chow diets containing 1%, 2%, 3%, or 4% calcium and 1.65% phosphorous, AquaMax 500RTM (2% Ca), and shrimp. Feeding trials lasted 28 days and changes in body size and bone density were measured. The calcium and phosphorous content of foods eaten by post-hatchlings...
Show moreThe calcium requirement in captive-raised hatchling loggerhead sea turtles (Caretta caretta) was investigated. Comparisons were made among turtles on 6 experimental diets and between captive and wild turtles. Diets consisted of trout chow diets containing 1%, 2%, 3%, or 4% calcium and 1.65% phosphorous, AquaMax 500RTM (2% Ca), and shrimp. Feeding trials lasted 28 days and changes in body size and bone density were measured. The calcium and phosphorous content of foods eaten by post-hatchlings in the sargassum were compared with captive diets. Results showed that shrimp was high in protein and low in calcium, with nearly twice as much P as Ca. The growth trials showed that turtles fed shrimp versus all other diets grew larger. There was no difference in total bone density of any treatment over the study. No signs of hypocalcemia were present, therefore, no lower limit for calcium requirement was determined in this study.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12708
- Subject Headings
- Loggerhead turtle, Sea turtles--Nutrition, Calcium in animal nutrition
- Format
- Document (PDF)
- Title
- Orientation of hatchling loggerhead sea turtles in response to the inclination of the magnetic field.
- Creator
- Light, Phillip Richard, Florida Atlantic University, Salmon, Michael, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Recent studies have shown that hatchling loggerhead sea turtles possess the ability to orient to the earth's magnetic field. These experiments did not identify the specific component of the field used by turtles to determine direction. One of the field's most important characteristics, inclination, has been implicated as the specific property used by birds to orient. This study investigated the possibility that sea turtles use the inclination of the earth's field in a similar manner. Results...
Show moreRecent studies have shown that hatchling loggerhead sea turtles possess the ability to orient to the earth's magnetic field. These experiments did not identify the specific component of the field used by turtles to determine direction. One of the field's most important characteristics, inclination, has been implicated as the specific property used by birds to orient. This study investigated the possibility that sea turtles use the inclination of the earth's field in a similar manner. Results show that turtles determine direction with the use of an inclination compass similar to the one used by birds to orient. This study has important implications regarding the mechanisms used by animals to orient and navigate.
Show less - Date Issued
- 1992
- PURL
- http://purl.flvc.org/fcla/dt/14787
- Subject Headings
- Loggerhead turtle, Animal orientation, Magnetic fields, Sea turtles--Migration
- Format
- Document (PDF)
- Title
- The magnetic compass of the loggerhead sea turtle (Caretta caretta L.): Can surface waves establish magnetic directional preference?.
- Creator
- Goff, Matthew Douglas, Florida Atlantic University, Salmon, Michael
- Abstract/Description
-
Hatchling loggerhead sea turtles emerge from their nests on oceanic beaches, crawl to the surf zone, and swim out to sea. How do turtles maintain oriented headings once they lose contact with land? I tested the hypothesis that by swimming into surface waves hatchlings establish an offshore heading (directional preference), and that once out to sea this heading is transferred to, and maintained by, a magnetic compass. This hypothesis was supported by laboratory and field experiments, described...
Show moreHatchling loggerhead sea turtles emerge from their nests on oceanic beaches, crawl to the surf zone, and swim out to sea. How do turtles maintain oriented headings once they lose contact with land? I tested the hypothesis that by swimming into surface waves hatchlings establish an offshore heading (directional preference), and that once out to sea this heading is transferred to, and maintained by, a magnetic compass. This hypothesis was supported by laboratory and field experiments, described herein. A directional preference can also be established by oriented crawling (from the nest to the surf zone). Thus hatchlings possess two mechanisms (crawling and swimming) for the establishment of an offshore heading. The use of these alternative mechanisms probably assures that turtles escape from shore under the broad range of conditions which they naturally encounter after emerging from their nests.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/15285
- Subject Headings
- Loggerhead turtle, Sea turtles--Orientation, Animal navigation
- Format
- Document (PDF)
- Title
- The effects of beach renourishment on the nesting behavior and hatching success of the loggerhead sea turtle on Jupiter Island, Florida: A seven year study.
- Creator
- Steinitz, Mary Julie., Florida Atlantic University, Salmon, Michael
- Abstract/Description
-
Jupiter Island is a barrier Island on the central East Coast of Florida whose beaches are subject to severe erosion. At intervals of several years, lost sand is replaced by the addition of sand ("renourishment") from other locations. In this study, I determined the effect of sand replacement on sea turtle nesting activity, and on the survival of nests placed on renourished and an adjacent natural beach. Renourishment caused a reduction in nesting activity by the turtles, which lasted about...
Show moreJupiter Island is a barrier Island on the central East Coast of Florida whose beaches are subject to severe erosion. At intervals of several years, lost sand is replaced by the addition of sand ("renourishment") from other locations. In this study, I determined the effect of sand replacement on sea turtle nesting activity, and on the survival of nests placed on renourished and an adjacent natural beach. Renourishment caused a reduction in nesting activity by the turtles, which lasted about two years. Thereafter, turtle nesting on renourished and control beaches was similar. There were no differences in nest survival between the two sites. Renourishment prevents the loss of beach and shoreline property, but is not necessarily beneficial to sea turtles.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/15292
- Subject Headings
- Loggerhead turtle, Sea turtles--Florida--Jupiter Island, Beach nourishment
- Format
- Document (PDF)
- Title
- The orientation and survival of loggerhead sea turtle hatchlings (Caretta caretta L.) in the nearshore environment.
- Creator
- Glenn, Lawrence, Florida Atlantic University, Salmon, Michael, Wyneken, Jeanette
- Abstract/Description
-
Hatchling sea turtles emerge at night from underground nests, crawl to the ocean, and swim out to sea. In this study, I determined how offshore orientation and shallow-water predation rates varied under natural (sand bottom and patch reef) and modified (submerged breakwater and open-beach hatchery) ecological circumstances. Hatchling offshore orientation in the sea was normal under all conditions; there were no significant differences in either scatter or direction among groups. However,...
Show moreHatchling sea turtles emerge at night from underground nests, crawl to the ocean, and swim out to sea. In this study, I determined how offshore orientation and shallow-water predation rates varied under natural (sand bottom and patch reef) and modified (submerged breakwater and open-beach hatchery) ecological circumstances. Hatchling offshore orientation in the sea was normal under all conditions; there were no significant differences in either scatter or direction among groups. However, predators (tarpon, snapper, barracuda, jacks, and grouper) took more hatchlings as they swam over submerged reefs, and after they entered the water in front of hatcheries. Predators were concentrated at both of these sites probably because prey (small fishes and invertebrates at patch reefs and turtles entering the water where nests were concentrated in hatcheries) occur in greater abundance.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/15282
- Subject Headings
- Loggerhead turtle, Sea turtles--Orientation, Animal navigation
- Format
- Document (PDF)
- Title
- Endogenous programs and the development of sea-finding orientation of loggerhead hatchlings (Caretta caretta).
- Creator
- Barrett, Christie A., Florida Atlantic University, Salmon, Michael
- Abstract/Description
-
This study's objective was to determine if the transfer of a crawling direction to a magnetic compass in loggerhead hatchling sea turtles ( Caretta caretta L.) was facilitated by how long the turtle crawled (an "endogenous timing" component). I first determined how long it took hatchlings to crawl from their nest to the ocean. Two types of experiments were then carried out. In the first, crawling time varied. In the second, both crawling time and direction varied. I found that at most beaches...
Show moreThis study's objective was to determine if the transfer of a crawling direction to a magnetic compass in loggerhead hatchling sea turtles ( Caretta caretta L.) was facilitated by how long the turtle crawled (an "endogenous timing" component). I first determined how long it took hatchlings to crawl from their nest to the ocean. Two types of experiments were then carried out. In the first, crawling time varied. In the second, both crawling time and direction varied. I found that at most beaches hatchlings crawled to the ocean in less than 5 min. My experiments showed that if crawls are too short (1 min), or too long (5 min), vector transfer is weakened compared to a 2 min crawl. I also found that a period of non-directional crawling interfered with the ability of a 2 min crawl to promote calibration. These results confirm that efficient transfer of a crawling vector, maintained by visual compass, to a swimming vector, maintained by a magnetic compass, depends upon an endogenous timing program in hatchlings. The temporal properties of that program are, in turn, apparently shaped by where their mothers place nests on the beach.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fcla/dt/13175
- Subject Headings
- Animal orientation, Animal navigation, Sea turtles--Orientation, Loggerhead turtle
- Format
- Document (PDF)
- Title
- The risk of hatchling loss to nearshore predators at a high-density loggerhead nesting beach in southeast Florida.
- Creator
- Stewart, Kelly Rhoda., Florida Atlantic University, Wyneken, Jeanette
- Abstract/Description
-
It has been recognized that mortality is high for juvenile stages of long-lived vertebrates such as sea turtles, however few studies have quantified mortality rates. The objective of this study was to assess the relative risk that hatchlings face in their first few minutes in the water, at the commencement of their offshore migration from a natural high-density nesting beach (Juno/Jupiter, FL). I followed 217 hatchlings at night by kayak, as they left the beach and documented the proportion...
Show moreIt has been recognized that mortality is high for juvenile stages of long-lived vertebrates such as sea turtles, however few studies have quantified mortality rates. The objective of this study was to assess the relative risk that hatchlings face in their first few minutes in the water, at the commencement of their offshore migration from a natural high-density nesting beach (Juno/Jupiter, FL). I followed 217 hatchlings at night by kayak, as they left the beach and documented the proportion surviving the initial 15 minutes in the water. Of these, 206 survived for an empirical survival rate of 95%. Tarpon were the most common predator observed. This survival rate is much higher than that previously observed at a hatchery (72%); this may be due to temporal and spatial variation in nest location at the natural beach. Juno and Jupiter beaches are therefore highly productive sea turtle rookeries.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12822
- Subject Headings
- Loggerhead turtle--Florida, Sea turtles--Mortality
- Format
- Document (PDF)
- Title
- Relocation and Flood Impacts on Loggerhead Sea Turtle (Caretta caretta) Nest Success.
- Creator
- Esposito, Lisa Anne, Milton, Sarah L., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Sea level rise threatens loggerhead sea turtle (Caretta caretta) nests laid close to the high tide line (HTL) with inundation from washover. Boca Raton, Florida is a relatively steep, dynamic beach with changes in beach morphology even during nonactive hurricane seasons. One potential solution to conserve sea turtle nests is to relocate nests laid at or below the HTL closer to the dune. In this study, I examined reproductive success for in situ vs relocated nests. Relocation did not decrease...
Show moreSea level rise threatens loggerhead sea turtle (Caretta caretta) nests laid close to the high tide line (HTL) with inundation from washover. Boca Raton, Florida is a relatively steep, dynamic beach with changes in beach morphology even during nonactive hurricane seasons. One potential solution to conserve sea turtle nests is to relocate nests laid at or below the HTL closer to the dune. In this study, I examined reproductive success for in situ vs relocated nests. Relocation did not decrease reproductive success, while nests left near the HTL were at risk of washout. During a dry season, nests that experienced one to three days of washover had significantly higher reproductive success than nests that experienced no washover. Relocation can be a useful method to preserve nests against sea level rise, but nonrelocated nests near the HTL may sometimes benefit from washover to cool the nests during hot and dry years.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014177
- Subject Headings
- Loggerhead turtle, Caretta caretta, Sea turtles--Nests
- Format
- Document (PDF)
- Title
- Incubation temperature, morphology, and loggerhead (Caretta caretta) sea turtle hatchling hydrodynamics.
- Creator
- Moyle, Alexis K., Milton, Sarah L., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
High nest incubation temperatures can result in numerous physiological and behavioral outcomes in sea turtle hatchlings, including body characteristics for efficient swimming. This project examined the effects of incubation temperature on yolk metabolization, body morphology, buoyancy, swimming kinematics, and blood chemistry to better understand variations in locomotor performance in loggerhead (Caretta caretta) sea turtle hatchlings of South Florida. Nest temperatures, body measurements,...
Show moreHigh nest incubation temperatures can result in numerous physiological and behavioral outcomes in sea turtle hatchlings, including body characteristics for efficient swimming. This project examined the effects of incubation temperature on yolk metabolization, body morphology, buoyancy, swimming kinematics, and blood chemistry to better understand variations in locomotor performance in loggerhead (Caretta caretta) sea turtle hatchlings of South Florida. Nest temperatures, body measurements, and blood samples were collected in conjunction with swim-trial force measurements and video recordings. Data suggest hatchlings from nests with higher incubation temperatures tend to be significantly smaller in size, less buoyant, and display lower power stroke frequencies. These variations between hatchling morphology and performance indicate hatchlings from high temperature nests (i.e., >33°C) may exhibit weaker swimming abilities. The results of this study provide a further understanding of the effect of incubation temperatures on hatchling physiology and early survival in their important frenzy period.
Show less - Date Issued
- 2023
- PURL
- http://purl.flvc.org/fau/fd/FA00014268
- Subject Headings
- Loggerhead turtle, Eggs--Incubation, Sea turtles--Ecology
- 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
- Nest placement by three species of sea turtles in southeast Florida, USA.
- Creator
- Wood, Lawrence D., Florida Atlantic University, Koch, Marguerite
- Abstract/Description
-
Studies of loggerhead, leatherback and green turtle nest distribution across beaches (between water and dune) have revealed conflicting random versus non-random patterns of nest placement. I examined nest placement on a southeast Florida beach (Juno and Jupiter) with average beach widths of 30 (natural) and 90 m (nourished beach) and tested slope as a proximal cue for nesting using long-term data sets and GPS technology. All three species had similar species-specific crawl lengths and nest...
Show moreStudies of loggerhead, leatherback and green turtle nest distribution across beaches (between water and dune) have revealed conflicting random versus non-random patterns of nest placement. I examined nest placement on a southeast Florida beach (Juno and Jupiter) with average beach widths of 30 (natural) and 90 m (nourished beach) and tested slope as a proximal cue for nesting using long-term data sets and GPS technology. All three species had similar species-specific crawl lengths and nest sites relative to distance from water, regardless of beach width. Loggerheads and leatherbacks crawled and nested significantly shorter median distances (8--14 m) relative to the water compared to greens (15 m), corresponding to sites of maximum productivity measured as percent hatchling success. The observed consistencies of crawl distance across all beach profiles suggest a strong evolutionary selection for a non-random crawl length at this study site, regardless of beach width and slight shifts in slope.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fcla/dt/13185
- Subject Headings
- Sea turtles--Florida--Palm Beach County, Loggerhead turtle--Florida, Sea turtles--Nests--Florida
- 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
-
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
- IMPACT OF DEVELOPED COASTLINE ON NESTING AND HATCHLING SEA TURTLES IN SOUTHEASTERN FLORIDA.
- Creator
- MANN, THOMAS MASON, Florida Atlantic University
- Abstract/Description
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The impact of coastline development on nesting sea turtles, nest contents, and hatchlings was investigated in southeastern Florida. There were 95-128 loggerhead (Caretta caretta) nests per mile on six miles of beach. Seventeen green turtle (Chelonia mydas) nests were found. Nesting females did not avoid lighted, developed beaches in favor of undeveloped beaches. Hatchling emergence bearings were measured at 397 nests, and ambient light intensities were correlated with the incidence of...
Show moreThe impact of coastline development on nesting sea turtles, nest contents, and hatchlings was investigated in southeastern Florida. There were 95-128 loggerhead (Caretta caretta) nests per mile on six miles of beach. Seventeen green turtle (Chelonia mydas) nests were found. Nesting females did not avoid lighted, developed beaches in favor of undeveloped beaches. Hatchling emergence bearings were measured at 397 nests, and ambient light intensities were correlated with the incidence of misorientation. Most hatchlings emerging where artificial light sources were visible were misoriented inland. From 0-96% of misoriented hatchlings were killed by automobiles, ghost crabs, or dessication. Mortality was greatest where hatchlings were able to enter roadways, and lowest where barriers prevented this. Analysis of post-emergence contents of 422 nests revealed that mortality within nests was greater on soft beaches with large-grained sand than on fine-grained, firmer beaches, and was increased by human footfalls and beach-cleaning machinery.
Show less - Date Issued
- 1977
- PURL
- http://purl.flvc.org/fcla/dt/13839
- Subject Headings
- Sea turtles--Florida--Palm Beach County, Sea turtles--Florida--Broward County, Green turtle, Loggerhead turtle
- Format
- Document (PDF)
- Title
- Polychlorinated biphenyls and p,p’-DDE in loggerhead and green postyearling Atlantic sea turtles.
- Creator
- McKim, James M., Jr., Johnson, Kenneth L., Harbor Branch Oceanographic Institute
- Date Issued
- 1983
- PURL
- http://purl.flvc.org/FCLA/DT/3176716
- Subject Headings
- Sea turtles, Polychlorinated biphenyls, Green turtle, Loggerhead turtle, Chelonia mydas, Caretta caretta, Pesticides
- Format
- Document (PDF)