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In migratory marine species, demographic estimates are often generated from capture-mark-recapture (CMR) studies conducted at terrestrial breeding sites. However, when logistical difficulties limit the geographic area of these surveys, demographic estimates are vulnerable to biases. We compared demographic rates generated from CMR data of nesting loggerhead turtles (Caretta caretta) collected between 2010 and 2017 at one focal site (Wassaw Island, Georgia, USA; 31.89° N, 80.97° W) with estimates generated from the same group of turtles but including all other nesting events from adjacent sites in Georgia, South Carolina, and North Carolina. We found that estimates of annual recruitment at the focal site were overestimated: each year, 29–45% putative first-time nesters at the focal beach had, in fact, nested on a different beach in a previous season. Estimates of clutch frequency and breeding frequency generated at the focal site were biased low and skewed towards values of one, while estimates for remigration interval were not significantly over- or underestimated. Additionally, estimates of annual and total population productivity in terms of clutches, eggs, and hatchlings were underestimated by more than half at the focal site. Our results show how weak fidelity to a focal nesting/tagging site can affect demographic estimates in marine turtle populations and highlight the need to reconsider estimates from other populations that might be vulnerable to similar biases.

Sea level rise (SLR) and disturbances from increased storm activity are expected to diminish coastal ecosystems available to nesting species by removing habitat and inundating nests during incubation. We updated the United States Geological Survey's (USGS) Coastal Vulnerability Index, which provides a qualitative and relative assessment of a coastal area's vulnerability to erosion and shoreline retreat as a function of SLR and other factors, for the South Atlantic Bight. We considered a eustatic SLR projection of 14 cm by 2030. We linked long-term survey data for 3 sea turtle species, 3 shorebird species, and 5 seabird species to future coastal erosion vulnerability to SLR to understand effects of future SLR on nesting habitats. Over 2,000 km (43%) of the South Atlantic Bight coastline is projected to have an increase in coastal erosion vulnerability by the 2030s, with respect to its present vulnerability. Future vulnerability of SLR-induced erosion along the South Atlantic Bight is spatially variable, and the 11 coastal study species also varied in their use of coastal habitats with high future coastal vulnerability to SLR. For example, only 23% of high-density nesting habitat for the brown pelican (Pelecanus occidentalis) is expected to be at increased vulnerability to SLR, whereas >70% of the high-nesting density habitat for 2 seabird species (gull-billed tern [Gelochelidon nilotica], sandwich tern [Thalasseus sandvicensis]) is predicted to have higher future coastal erosion vulnerability by 2030. We provide predictions for the level of susceptibility of the study species to erosion from future SLR, which is the first step in managing coastal species for the changing environmental conditions associated with climate change and SLR. (c) 2019 The Authors. Journal of Wildlife Management Published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. USFWS; South Atlantic Landscape Conservation Cooperative The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the U.S. Fish and Wildlife Service. Sea turtle data were provided by the Florida Fish and Wildlife Conservation Commission Statewide Nesting Beach Survey, Canaveral National Seashore, University of Central Florida Marine Turtle Research Group, Archie Carr National Wildlife Refuge survey, Georgia Department of Natural Resources Sea Turtle Conservation Program, South Carolina Department of Natural Resources Marine Turtle Conservation Program, and North Carolina Wildlife Resources Commission Sea Turtle Project. D. Griffin provided data and information for South Carolina sea turtles. Seabird and shorebird nesting and occupancy data were provided by the Florida Fish and Wildlife Conservation Commission, Georgia Department of Natural Resources, South Carolina Department of Natural Resources, and North Carolina Wildlife Resources Commission. J. Brush provided the Florida seabird and shorebird data and background information. We sincerely thank the individual permit holders and volunteers who collected the sea turtle data for Florida, Georgia, North Carolina, and South Carolina, and the Air Force, 45th Space Wing. We appreciate the contributions from S. Pierre and M. Auman in organizing the biological data. We also thank S. Maddock and W. Golder for wintering piping plover data. The authors thank S. Dellinger and J. Heisey for their contributions to the wave gauge data analyses. We thank S. Hagan and D. Passeri for their contribution to the shoreline change analysis. Funding for Florida's sea turtle monitoring program has been provided by grants to the Florida Wildlife Commission under Project E -7 from the USFWS and by proceeds from sales of the Florida marine turtle license plates. This work was funded by the South Atlantic Landscape Conservation Cooperative.

Population assessments conducted at reproductive sites of migratory species necessitate understanding the foraging-area origins of breeding individuals. Without this information, efforts to contextualize changes in breeding populations and develop effective management strategies are compromised. We used stable isotope analysis of tissue samples collected from loggerhead sea turtles (Caretta caretta) nesting at seven sites in the Northern Recovery Unit (NRU) of the eastern United States (North Carolina, South Carolina and Georgia) to assign females to three separate foraging areas in the Northwest Atlantic Ocean (NWA). We found that the majority of the females at NRU nesting sites (84.4%) use more northern foraging areas in the Mid-Atlantic Bight, while fewer females use more proximate foraging areas in the South Atlantic Bight (13.4%) and more southerly foraging areas in the Subtropical Northwest Atlantic (2.2%). We did not find significant latitudinal or temporal trends in the proportions of NRU females originating from different foraging areas. Combining these findings with previous data from stable isotope and satellite tracking studies across NWA nesting sites showed that variation in the proportion of adult loggerheads originating from different foraging areas is primarily related differences between recovery units: individuals in the NRU primarily use the Mid-Atlantic Bight foraging area, while individuals from the three Florida recovery units primarily use the Subtropical Northwest Atlantic and Eastern Gulf of Mexico foraging areas. Because each foraging area is associated with its own distinct ecological characteristics, environmental fluctuations and anthropogenic threats that affect the abundance and productivity of individuals at nesting sites, this information is critical for accurately evaluating population trends and developing effective region-specific management strategies.

Nesting beach management is a vital element of the population recovery efforts for the vulnerable loggerhead sea turtle (Caretta caretta) across the globe. In the southeast United Sates, turtle nests are threatened by numerous anthropogenic and natural threats, including predation of eggs by native and non-native predators. We analyzed loggerhead nest predation and other egg; loss using an exceptional 10-year data set (2009–2018) that covered nesting beaches on 12 islands on the Georgia coast. Our objectives were to 1) determine which predators cause the greatest loss of loggerhead sea turtle eggs, 2) evaluate whether non-native species have a higher; rate of predation than native species, and 3) compare predation rates to other major sources of egg loss across these islands. Our results show that under current strategies for nest management: 1) non-native feral hogs and native raccoons have the greatest impact as predators on sea turtle eggs; 2) non-native predators have caused significantly more egg loss across Georgia’s coast than native species, but the impact varies greatly by species; and 3) losses to predation are similar in magnitude to post-management losses from tides and storms over the last decade. We recommend the continued use of multiple management techniques, including nest screening and; targeted predator management, but caution that predator controls should be focused on those demonstrated to cause significant losses in order to prioritize conservation funding.

Loggerhead sea turtle (Caretta caretta) nesting-beach management is an integral component of population recovery efforts for this internationally threatened species. In Georgia, nests threatened by tidal inundation are commonly relocated to elevated dunes, and screens are placed over nests to prevent depredation. The objective of this study was to examine the effects of nest relocation and nest screening on both hatching success (proportion of successfully hatched eggs) and emergence success (proportion of hatchlings successfully emerging from the egg chamber) at Sapelo Island, Georgia. Results suggest that high hatching and emergence success rates can be maintained on Sapelo Island without nest relocation. Predator screens do not appear to affect hatching or emergence success and should continue to be used to protect nests from depredation.

Nest counts are often used as indices for nesting female abundance in marine turtle monitoring, but accurately interpreting nest count trends requires context on the scale of demographic connectivity and estimates of reproductive parameters. Weak nest site fidelity (NSF) relative to the scale of tagging effort may bias parameter estimates. The reproductive ecology of Northern Recovery Unit (NRU) loggerhead turtles (Caretta caretta) was assessed through subpopulation-scale genetic capture-recapture via clutch sampling from approximately 1000 km of coastline from Georgia to Maryland, USA (30.75–38.06°N and 75.24–81.45°W). Of 20,682 clutches recorded from 2010 to 2012, 20,222 sampled clutches were assigned to 5684 unique females through microsatellite genotyping. Approximately 73% of females detected laying multiple clutches deposited them within a 20-km span, suggesting the possibility of demographic structuring across NRU rookeries that warrants further investigation. Estimated clutch frequencies (ECF) generated from open robust design modeling were 4.28 (4.02–4.54) in 2010, 4.63 (4.45–4.80) in 2011, and 4.57 (4.28–4.77) in 2012, and were significantly higher than observed clutch frequencies. ECF generated from single-island data were biased low by 23–50% relative to those from regional genetic tagging. Among females that nested at least once on a physical tagging beach, 54% also nested elsewhere, with 81% of these “permanently” emigrating during the nesting season. This pattern of relatively strong NSF, but distributed across multiple nearby islands, confounded modeling of detection in single-island datasets and highlights the need for regional coverage for generating robust estimates of demographic parameters for marine turtles.

From 1998 to 2008, 68 adult female loggerhead sea turtles (Caretta caretta) were instrumented with platform transmitter terminals at nesting beaches in Georgia, North Carolina (NC) and South Carolina (SC) on the East Coast of the United States of America (30°48′N, 81°28′W to 33°51′N, 77°59′W). The majority of post-nesting loggerheads (N = 42, 62 %) migrated to foraging habitats in the Mid-Atlantic Bight during May–October, with a subsequent migration occurring during November–March to foraging habitats south of Cape Hatteras, NC. Nine (13 %) loggerheads initially foraged in the near-shore, coastal areas of the South Atlantic Bight, but moved to offshore habitats—closer to the Gulf Stream—during November–March, while fourteen (21 %) loggerheads remained in foraging areas along the mid-continental shelf off of the eastern coast of Florida and/or continued southward to Florida Bay and the Bahamas. The present study delineates important, post-nesting foraging habitats and migration corridors where loggerheads may interact with commercial fisheries—providing managers opportunities to develop and implement optimally effective conservation actions for the recovery of this threatened species.

Recovery of loggerhead turtle Caretta caretta populations depends on many factors, including reducing anthropogenic mortality of adult turtles. Shrimp trawls are considered a major source of mortality for adult loggerhead turtles despite the mandatory use of turtle excluder devices. We modeled scenarios for reducing the likelihood of interaction between nesting adult loggerhead turtles and shrimp trawlers operating off the coast of Georgia during the nesting season (May–August). We used satellite telemetry and aerial surveys to describe the distribution patterns of nesting adult female turtles (2004–2005; n = 22) and shrimp trawls (1999–2005), respectively, across waters adjacent to the Georgia shoreline. Adult female turtles and shrimp trawlers both occupied state waters extensively during the nesting season. Turtles tended to have long, narrow home ranges that were located parallel to shore and that overlapped with the shrimp trawl distribution, which showed a slight grouping around deep channe...

The southeastern USA hosts the largest nesting concentration of loggerhead turtles Caretta caretta in the Atlantic. Regionally significant nesting also occurs along the Caribbean coast of Mexico, in Cuba, and in the Bahamas. Previous studies of North Atlantic loggerhead turtle rookeries based on a 380 bp fragment of the mitochondrial control region supported recognition of 8 demographically independent nesting populations (management units) in the Northwest Atlantic in addition to Cape Verde in the eastern Atlantic. Recent analysis of expanded mitochon- drial control region sequences revealed additional genetic diversity and increased population structure between western and eastern Atlantic loggerhead turtle rookeries. We se quenced an 817 bp mitochondrial DNA fragment in 2427 samples from nesting beaches in the southeastern USA, Cay Sal Bank, Bahamas, and Quintana Roo, Mexico. Pairwise FST comparisons, pairwise exact tests of population differentiation, and analysis of molecular variance support previously proposed management unit designations and additionally indicate that southeastern and south- western Florida rookeries should be recognized as distinct management units. Therefore, North- west Atlantic loggerhead turtle rookeries can be subdivided into 10 management units, corre- sponding to the beaches from (1) Virginia through northeastern Florida, (2) central eastern Florida, (3) southeastern Florida, (4) Dry Tortugas, Florida, (5) Cay Sal, Bahamas, (6) southwestern Cuba, (7) Quintana Roo, Mexico, (8) southwestern Florida, (9) central western Florida, and (10) northwestern Florida. We confirmed increased resolution of stock structure between many North- west Atlantic management units and the Cape Verde rookery with the expanded control region haplotypes.

Aim Although satellite tracking has yielded much information regarding the migrations and habitat use of threatened marine species, relatively little has been published about the environmental niche for loggerhead sea turtles Caretta caretta in north-west Atlantic waters. Location North Carolina, South Carolina and Georgia, USA. Methods We tracked 68 adult female turtles between 1998 and 2008, one of the largest sample sizes to date, for 372.2 ± 210.4 days (mean ± SD). Results We identified two strategies: (1) ‘seasonal’ migrations between summer and winter coastal areas (n = 47), although some turtles made oceanic excursions (n = 4) and (2) occupation of more southerly ‘year-round’ ranges (n = 18). Seasonal turtles occupied summer home ranges of 645.1 km2 (median, n = 42; using α-hulls) predominantly north of 35 ° latitude and winter home ranges of 339.0 km2 (n = 24) in a relatively small area on the narrow shelf off North Carolina. We tracked some of these turtles through successive summer (n = 8) and winter (n = 3) seasons, showing inter-annual home range repeatability to within 14.5 km of summer areas and 10.3 km of winter areas. For year-round turtles, home ranges were 1889.9 km2. Turtles should be tracked for at least 80 days to reliably estimate the home range size in seasonal habitats. The equivalent minimum duration for ‘year-round’ turtles is more complex to derive. We define an environmental envelope of the distribution of North American loggerhead turtles: warm waters (between 18.2 and 29.2 °C) on the coastal shelf (in depths of 3.0–89.0 m). Main conclusions Our findings show that adult female loggerhead turtles show predictable, repeatable home range behaviour and do not generally leave waters of the USA, nor the continental shelf (

The southeastern United States supports one of two large loggerhead turtle (Caretta caretta) nesting aggregations worldwide and is therefore critical to global conservation and recovery efforts for the species. Previous studies have established the presence of four demographically distinct nesting populations (management units) corresponding to beaches from (1) North Carolina through northeastern Florida, (2) peninsular Florida, (3) the Dry Tortugas, and (4) northwest Florida. Temporal and geographic genetic structure of the nesting aggregation was examined utilizing partial mitochondrial control region haplotype frequencies from 834 samples collected over the 2002 through 2008 nesting seasons from 19 beaches as well as previously published haplotype data. Most rookeries did not exhibit interannual genetic variation. However, the interannual variation detected did significantly impact the interpretation of spatial genetic structure in northeastern Florida. Based on pairwise F ST comparisons, exact tests of population differentiation, and analysis of molecular variance, the present study upholds the distinctiveness of the four currently recognized management units and further supports recognition of discrete central eastern, southern (southeastern and southwestern), and central western Florida management units. Further subdivision may be warranted, but more intensive genetic sampling is required. In addition, tools such as telemetry and mark-recapture are needed to complement genetic data and overcome limitations of genetic markers in resolving loggerhead turtle rookery connectivity in the southeastern USA.

Collisions with marine vessels represent a significant threat to many marine vertebrates, including whales, dolphin, manatees, and sea turtles. Many recovered turtles display injuries that appear to result from interactions with marine vessels and their associated propulsion systems, yet the details of these interactions and the potential for reducing their lethality have not been previously investigated. This paper describes a series of experiments designed to investigate the type and severity of damage inflicted on full-scale model loggerhead sea turtles struck by small vessels, and the potential for reducing the likelihood of fatal interactions by modifying either the vessel propulsion system or operational characteristics. Artificial carapaces were developed to mimic selected material properties of a natural loggerhead carapace. These were secured to frames to yield models with size, mass, and density representative of real animals. The model turtles were subjected to impact by small (3–6 m) vessels with traditional outboard, jet outboard, and inboard jet propulsion systems under controlled conditions in the field. Dependence of catastrophic injury on vessel speed, model depth below the water surface, and propulsion system was investigated via repeated tests. The effectiveness of two commercial propeller guards was also investigated. Results indicate that vessel speed does significantly influence the likelihood of catastrophic damage, whereas depth in the water column does not. Propeller guards were ineffective at planing speed and only slightly helpful at idle speed. Both tested jet propulsion systems yielded dramatic improvements in animal safety compared to a traditional outboard and propeller arrangement. Results thus suggest that appropriate changes in both vessel operation and configuration can reduce threats to sea turtles, and likely other marine organisms.

Tagging studies on nesting beaches are commonly used to estimate nesting frequency, remigration interval and nesting population size for marine turtle rookeries. Estimates of these demographic parameters from tagging projects may be biased because of the small scale of tagging efforts relative to female nest site fidelity and the logistical difficulty of intercepting all nesting females. Therefore, alternative and supplemental means of individual identification of nesting females are required. We demonstrate that maternal nuclear microsatellite DNA can be isolated from unincubated eggshells of the loggerhead sea turtle (Caretta caretta) through comparison of DNA extracted from 59 eggs collected within 15 h of oviposition and DNA derived from skin samples from respective nesting females. Scorable microsatellite genotypes were produced in 897 of 994 (90.2%) single-locus egg amplifications attempted. Among eggs from known females, 730 of 748 (97.6%) single-locus, egg-derived genotypes matched the respective skin-derived genotypes. Allelic dropout was the most common type of error, followed by the presence of nonmaternal, presumably paternal, alleles. Genotypes derived from unincubated eggshells permit individual assignment of nests and therefore demographic parameter estimates for loggerhead turtle nesting populations, despite genotyping errors that require further optimization. Although sampling unincubated eggs is destructive, this technique is noninvasive to nesting females and is applicable in marine turtle population genetics studies when individual resolution is required but direct interception of nesting females is undesirable or logistically infeasible.

The effectiveness of recovery plans for threatened and endangered species has been questioned in academic and political domains. A comprehensive assessment of species recovery plans concluded that quantification and prioritization of threats have received insufficient attention, which contributes to the failure of some plans. On the basis of this assessment, we developed and implemented a detailed analysis of threats in the Recovery Plan for the Northwest Atlantic Population of the Loggerhead Sea Turtle (Caretta caretta), produced by the National Marine Fisheries Service and US Fish and Wildlife Service. The analytical approach that we designed and summarize here provides an objective process for quantifying known threats and prioritizing recovery actions in terms of their relative impact on population growth rate (λ) of the loggerhead sea turtle. Although this process was developed for loggerhead sea turtles, it can be applied to other species.

The loggerhead sea turtle (Caretta caretta) is a federally threatened species and listed as endangered by the World Conservation Union (IUCN). We describe primers and polymerase chain reaction (PCR) conditions to amplify 11 novel tetranucleotide microsatellite loci from the loggerhead sea turtle. We tested primers using samples from 22 females that nested at Melbourne Beach, Florida (USA). Primer pairs yielded an average of 11.2 alleles per locus (range of 4–24), an average observed heterozygosity of 0.83 (range 0.59–0.96), and an average polymorphic information content of 0.80 (range 0.62–0.94). We also demonstrate the utility of these primers, in addition to primers for 15 loci previously described, for amplifying microsatellite loci in four additional species representing the two extant marine turtle families: olive ridley (Lepidochelys olivacea), hawksbill (Eretmochelys imbricata), green turtle (Chelonia mydas), and leatherback (Dermochelys coriacea).

We describe primers and polymerase chain reaction conditions to amplify 15 tetranucleotide microsatellite loci from the loggerhead sea turtle ( Caretta caretta ). The primers were tested on 30 individuals that nested along the Georgia, USA coast. The primer pairs developed in this study yielded an average of 13.9 alleles per locus (range of 10–21), an average observed heterozygosity of 0.91 (range 0.79–1.00), and an average polymorphic information content of 0.88 (range 0.84–0.92).

The ''landscape of fear'' model has been proposed as a unifying concept in ecology, describing, in part, how animals behave and move about in their environment. The basic model predicts that as an animal's landscape changes from low to high risk of predation, prey species will alter their behavior to risk avoidance. However, studies investigating and evaluating the landscape of fear model across large spatial scales (tens to hundreds of thousands of square kilometers) in dynamic, open, aquatic systems involving apex predators and highly mobile prey are lacking. To address this knowledge gap, we investigated predator- prey relationships between tiger sharks (Galeocerdo cuvier) and loggerhead turtles (Caretta caretta) in the North Atlantic Ocean. This included the use of satellite tracking to examine shark and turtle distributions as well as their surfacing behaviors under varying levels of home range overlap. Our findings revealed patterns that deviated from our a priori predictions based on the landscape of fear model. Specifically, turtles did not alter their surfacing behaviors to risk avoidance when overlap in shark-turtle core home range was high. However, in areas of high overlap with turtles, sharks exhibited modified surfacing behaviors that may enhance predation opportunity. We suggest that turtles may be an important factor in determining shark distribution, whereas for turtles, other life history trade-offs may play a larger role in defining their habitat use. We propose that these findings are a result of both biotic and physically driven factors that independently or synergistically affect predator-prey interac- tions in this system. These results have implications for evolutionary biology, community ecology, and wildlife conservation. Further, given the difficulty in studying highly migratory marine species, our approach and conclusions may be applied to the study of other predator- prey systems.

Juvenile loggerhead turtles (Caretta caretta) from West Atlantic nesting beaches occupy oceanic (pelagic) habitats in the eastern Atlantic and Mediterranean, whereas larger juvenile turtles occupy shallow (neritic) habitats along the continental coastline of North America. Hence the switch from oceanic to neritic stage can involve a trans-oceanic migration. Several researchers have suggested that at the end of the oceanic phase, juveniles are homing to feeding habitats in the vicinity of their natal rookery. To test the hypothesis of juvenile homing behaviour, we surveyed 10 juvenile feeding zones across the eastern USA with mitochondrial DNA control region sequences (N = 1437) and compared these samples to potential source (nesting) populations in the Atlantic Ocean and Mediterranean Sea (N = 465). The results indicated a shallow, but significant, population structure of neritic juveniles (ΦST = 0.0088, P = 0.016), and haplotype frequency differences were significantly correlated between coastal feeding populations and adjacent nesting populations (Mantel test R2 = 0.52, P = 0.001). Mixed stock analyses (using a Bayesian algorithm) indicated that juveniles occurred at elevated frequency in the vicinity of their natal rookery. Hence, all lines of evidence supported the hypothesis of juvenile homing in loggerhead turtles. While not as precise as the homing of breeding adults, this behaviour nonetheless places juvenile turtles in the vicinity of their natal nesting colonies. Some of the coastal hazards that affect declining nesting populations may also affect the next generation of turtles feeding in nearby habitats.

An increase in the incidence of debilitated loggerhead sea turtle (Caretta caretta) strandings in the southeastern United States has been observed in recent years. These turtles are characterized by emaciation and heavy burdens of external and internal parasites, and bacterial infections, but the underlying cause of their condition is unknown. To investigate further the causes of these strandings, a health assessment was performed on stranded, debilitated loggerhead turtles, and contaminant concentrations in various tissues were compared to those from healthy turtles. This portion of the study investigated the potential role of mercury (Hg) toxicity in the debilitated condition described above. Hematocrit, total protein, albumin, globulin, glucose, calcium, lymphocyte counts, heterophil:lymphocyte ratios, aspartate aminotransferase, uric acid, sodium, and chloride were altered in debilitated loggerheads relative to healthy animals. However, none of the aforementioned health indicators correlated with Hg concentrations in either red blood cells (RBCs) or plasma. The Hg concentration in RBCs was 129+/-72 (mean+/-standard deviation) times higher than in plasma, causing a significant dilution of Hg in whole blood due to extreme anemia. Mercury concentrations in RBCs (73.7+/-21.2 ng/g) and scutes (455+/-57 ng/g) from debilitated turtles were similar to or lower than those reported for healthy animals, indicating no elevation in Hg exposure before and during the progression of this condition. These findings suggest that Hg toxicity does not play a role in the debilitated loggerhead condition observed in the southeastern United States.

The health status of 83 loggerhead sea turtles (Caretta caretta; 39 foraging, 31 nesting, and 13 stranded turtles) was analyzed using physical examinations, hematology, plasma biochemistry, plasma protein electrophoresis, and toxicologic parameters. Significant differences were noted in a number of health parameters between turtles exhibiting each of these behaviors. On physical examinations, stranded turtles had the highest prevalence of heavy carapace epibiont loads, miscellaneous abnormalities, emaciation, and weakness. Differences in hematologic values included a lower packed cell volume, higher number of lymphocytes, and lower number of monocytes in stranded turtles; lower white blood cell counts in foraging turtles; and significant differences in total solid values among turtles exhibiting all behaviors with the lowest values in stranded turtles and the highest values in nesting turtles. Differences in plasma biochemistry values included the highest uric acid, creatine kinase, and CO(2) values in stranded turtles; the highest glucose and potassium values in foraging turtles; and the highest cholesterol and triglyceride values, and lowest alanine aminotransferase, in nesting turtles. Differences in total protein, albumin, and globulin were found using plasma biochemistry values, with lowest values in stranded turtles and highest values in nesting females, whereas differences in blood urea nitrogen between turtles included the lowest values in nesting turtles and the highest in foraging turtles. Plasma organochlorine and polychlorinated biphenyl levels were below their limits of quantification in the 39 foraging, 11 nesting, and three stranded turtles tested. A statistically significant difference was noted in the level of whole blood mercury between the 23 foraging and 12 nesting turtles tested. There was no difference in arsenic or lead levels between turtles exhibiting any of the three behaviors. Although a few limitations exist with the present study and include unknown ambient temperatures, turtle handling times that varied from 15 min to 53 min per turtle, and the use of a different laboratory for processing complete blood counts and plasma biochemistries in stranded versus foraging and nesting turtles, we provide baseline blood values for two cohorts (foraging and nesting) of loggerhead sea turtles on the coast of Georgia. Additionally, we demonstrate significant differences in clinical findings and blood parameters between foraging, nesting, and stranded loggerhead turtles in the region.

Managing colonially nesting wading bird populations is often hampered by the lack of reliable information on colony sizes and population status. Therefore, we evaluated 9 techniques for accuracy and precision of counting great blue heron (Ardea herodias) nests in South Carolina. We examined accuracy by comparing percent deviation of technique estimates from corresponding ground counts. Precision of the different techniques was evaluated by comparing 95% confidence intervals for predicting individual colony size and the statewide nesting population. Techniques included point count, perimeter count, 40% sampling with 4-m-wide transects, 20% sampling with 2- and 4-m-wide transects, aerial estimate, aerial count, aerial photographic count, and post-nesting ground count. Error rates varied among techniques and for colonies containing 320 nests) colonies, post-nesting ground counts, aerial estimates, and all transect techniques had acceptable confidence interval widths ( 20%). Although couting techniques were not precise enough to be used for an estimate of the statewide nesting effort, managers using a combination of aerial counts of small (

Capture–mark–recapture (CMR) studies on marine turtle nesting beaches provide data on reproductive periodicity that inform population trends and models. Annual survival is estimated from observations of remigration, the return of females in subsequent nesting seasons. However, a significant proportion of tagged females are never encountered remigrating in many studies, presumably due to weak nest site fidelity (NSF). We employed a genetic CMR approach based on subpopulation-scale clutch sampling to conduct a 5-year evaluation of inter-seasonal recapture rates and NSF for Northern Recovery Unit loggerhead turtles (Caretta caretta). Of 1770 females genetically tagged from Georgia through Maryland in 2010, 1156 (65%) remigrated between 2011 and 2015. Inter-seasonal NSF, measured as shifts in median latitude nesting locations between years, was highly variable among individuals but strong overall (mean: 15.08 (± 44.61) km, median: 1.84 km). Among three focal beaches with nocturnal tagging projects, 69 of 173 females (40%) remigrated onsite whereas 115 (66%) were detected overall. Regional genetic sampling therefore yielded significantly higher inter-seasonal recapture rates, which may improve precision in future survival analyses. However, despite sampling ~ 1000 km with high annual detection probabilities (p* ≥ 0.94), 35% of 2010-females were not detected remigrating. Several non-exclusive hypotheses to explain these remaining “missing” remigrants should be considered: longer remigration intervals, imperfect detection within the study area, emigration to Florida, anthropogenic mortality, and natural mortality or senescence. This genetic tagging approach can be applied over large spatial scales where nesting densities permit, better characterizing inter-seasonal dispersal.