Leatherback Research Articles

Missing Data in Sea Turtle Population Monitoring: A Bayesian Statistical Framework Accounting for Incomplete Sampling

Monitoring how populations respond to sustained conservation measures is essential to detect changes in their population status and determine the effectiveness of any interventions. In the case of sea turtles, their populations are difficult to assess because of their complicated life histories. Ground-derived clutch counts are most often used as an index of population size for sea turtles; however, data are often incomplete with varying sampling intensity within and among sites and seasons. To address these issues, we: (1) develop a Bayesian statistical modelling framework that can be used to account for sampling uncertainties in a robust probabilistic manner within a given site and season; and (2) apply this to a previously unpublished long-term sea turtle dataset (n = 17 years) collated for the Republic of the Congo, which hosts two sympatrically nesting species of sea turtle (leatherback turtle [Dermochelys coriacea] and olive ridley turtle [Lepidochelys olivacea]). The results of this analysis suggest that leatherback turtle nesting levels dropped initially and then settled into quasi-cyclical levels of interannual variability, with an average of 573 (mean, 95% prediction interval: 554–626) clutches laid annually between 2012 and 2017. In contrast, nesting abundance for olive ridley turtles has increased more recently, with an average of 1,087 (mean, 95% prediction interval: 1,057–1,153) clutches laid annually between 2012 and 2017. These findings highlight the regional and global importance of this rookery with the Republic of the Congo, hosting the second largest documented populations of olive ridley and the third largest for leatherback turtles in Central Africa; and the fourth largest non-arribada olive ridley rookery globally. Furthermore, whilst the results show that Congo’s single marine and coastal national park provides protection for over half of sea turtle clutches laid in the country, there is scope for further protection along the coast. Although large parts of the African coastline remain to be adequately monitored, the modelling approach used here will be invaluable to inform future status assessments for sea turtles given that most datasets are temporally and spatially fragmented.

Balancing conservation and commerce: A shadow value viability approach for governing bycatch

The losses from extinction events are not well-known, making an expected net benefits approach to conservation problems difficult to implement. A viable control strategy instead focuses on limiting the risk of extinction to some acceptably low level at the least possible cost. Here we describe a shadow value viability approach for solving conservation problems with irreversible thresholds with dynamic programming. A social planner calculates the minimal (virtual) level of loss from extinction that would trigger sufficient action to avoid extinction with the desired confidence. The cost-effective policy then arises from acting as if the resulting shadow value is real. We demonstrate the method in a numerical application to the conservation of the Pacific leatherback turtle population, which co-mingles with the Pacific swordfish fishery. We show how the cost-effective outcome can be achieved among decentralized fishers by using the planner’s shadow value to set market-based instruments for managing turtle bycatch. This approach translates the species viability objective into economic terms so conservation and commercial harvest can be rationally integrated.

09. First live stranding of a leatherback sea turtle [Dermochelys coriacea] in Alagoas, north-east Brazil

09. First live stranding of a leatherback sea turtle [Dermochelys coriacea] in Alagoas, north-east Brazil

The Value of Characters in Tabob Folklore (the Leatherback Turtle) in Southeast Maluku

This study aims to (1) describe the form of character values in the Tabob folklore, Southeast Maluku district. (2) Describe the function of the Southeast Maluku Tabob folklore. (3) Analyzing the character values of the Southeast Maluku Tabob folklore. The data in this study are, in the form of written or spoken words from the informants. Sources of data in this study are informants, documents of informants, informants or the community who provide information about local fishermen's folklore. Other data sources such as. The data collection techniques are observation, interview, documentation, and literature study. The data analysis technique used is data reduction, data presentation, and drawing conclusions. The results of the study show that the process of revealing intermediate values in the three folk tales of fishermen, by using respondents or fishermen and local communities who understand the three folklores to provide data. This can be seen from some of the respondents or fishermen who are able to provide data related to the three folklores of Southeast Maluku fishermen well and implemented.

Anatomy of the heart of the leatherback turtle.

Non‐crocodylian reptiles have hearts with a single ventricle, which is partially separated by a muscular ridge that provides some separation of blood flows. An exceptional situation exists in monitor lizards and pythons, where the ventricular left side generates a much higher systolic blood pressure than the right side, thus resembling mammals and birds. This functional division of the ventricle depends on a large muscular ridge and may relate to high metabolic demand. The large leatherback turtle (<1000 kg), with its extensive migrations and elevated body temperatures, may have similar adaptations. We report on the anatomy of the hearts of two leatherback turtles. One stranded in Ballum, Denmark in 2020, and was examined in detail, supplemented by observations and photos of an additional stranding specimen from Canada. The external morphology of the leatherback heart resembles that of other turtles, but it is large. We made morphometric measurements of the Ballum heart and created an interactive 3D model using high‐resolution MRI. The volume of the ventricle was 950 ml, from a turtle of 300 kg, which is proportionally almost twice as large as in other reptiles. The Ballum heart was compared to MRI scans of the hearts of a tortoise, a python, and a monitor lizard. Internally, the leatherback heart is typical of non‐crocodylian reptiles and did not contain the well‐developed septation found in pythons and monitor lizards. We conclude that if leatherback turtles have exceptional circulation needs, they are sustained with a relatively large but otherwise typical non‐crocodylian reptile heart.

The effects of nest location and beach environment on hatching success for leatherback (Dermochelys coriacea) and green (Chelonia mydas) sea turtles on Bioko Island, Equatorial Guinea

Hatching success of sea turtle eggs can be reduced by a variety of biotic and abiotic factors. This study of the nesting ecology of leatherback (Dermochelys coriacea) and green (Chelonia mydas) sea turtles, investigated how several environmental factors and beach characteristics on Bioko Island, Equatorial Guinea influence sea turtle reproductive success. Average hatching success was 40.4% for green turtles and 41.73% for leatherback turtles. For leatherback turtles, clutch elevation relative to the high tide line (HTL) was found to be the most influential factor in determining hatching success, highlighting the sensitivity of this species to sea-level rise (SLR). Multiple linear regression analysis demonstrated that nest distance to vegetation, temperature, sand grain size, location on the beach, and sand conductivity also played significant roles in leatherback clutch hatching success. For leatherback clutches, 33% percent of nests were affected by inundation and 17% by predation. An optimum clutch elevation range for leatherback turtles was identified, where a distinct increase in hatching success was observed between − 0.286 and − 0.0528 m above the HTL. For green sea turtles, 64% of experimental nests were affected by predation, confounding conclusions about the roles of environmental characteristics in green turtle hatching success. We propose further investigation into influential characteristics in green turtle nests and confirmation of the observed optimum elevation range on Bioko Island and other nesting grounds. Identified sensitivities of each species to SLR and beach characteristics will be used to encourage the government of Equatorial Guinea to consider the vulnerability of their resident turtle populations when planning for future coastal development.

Differences in visual perception are correlated with variation in sea-finding behaviour between hatchling leatherback, Dermochelys coriacea, and loggerhead, Caretta caretta, marine turtles

After completing embryonic development, marine turtle hatchlings emerge from their subsurface nest, generally at night, and crawl to the ocean (‘sea finding’). That response depends upon the ability of the turtles to discriminate between the brighter seaward versus a dimmer landward horizon, followed by a positive phototaxis. While the crawls of most marine turtle hatchlings are well oriented and straight, those of leatherback hatchlings are sometimes interrupted by bouts of circling. We conducted experiments comparing the orientation and crawling behaviour of leatherbacks to those of loggerhead hatchlings to determine why those differences occur. The two species did not differ in the light spectra attracting the hatchlings, but leatherback thresholds for detection and for intensity discrimination were significantly higher than those of loggerheads. At the nesting beach, loggerheads under full (bright) or new (darker) moon conditions crawled straight to the ocean; circling rarely occurred. Leatherback crawls under a full moon were indistinguishable from those of loggerheads, but during new moon trials, when horizon brightness differences approached leatherback intensity discrimination thresholds, circling increased significantly. We conclude that circling is probably used by leatherbacks to reinforce orientation decisions when horizon cues become more difficult to discern. Circling could be costly as it lengthens the crawl and increases exposure to terrestrial predators. We hypothesize that those costs persist because other visual adaptations affecting sensitivity enhance the ability of leatherbacks to detect prey, mates or favourable habitats in an open ocean environment. • We compared leatherback and loggerhead hatchlings' phototaxis responses. • Leatherbacks were less sensitive to wavelengths of 340–580 nm than loggerheads. • Under full moon, both species crawled directly from the nest to the sea. • Under new moon, leatherbacks were less accurate; loggerheads remained unchanged. • These responses may reflect sea-finding orientation–foraging efficiency trade-offs.

Recent observations of Dermochelys coriacea (Vandelli, 1761), in the waters of Pacific Panama

The situation of the Eastern Tropical Pacific subpopulation of the leatherback sea turtle (Dermochelys coriacea) is critical due to the drastic declines of nesting females. Evidence of the presence of leatherback sea turtles along the Pacific coast of Panama is anecdotal and is based on the local knowledge of local residents. I present here an uncommon observation of a subadult and an adult D. coriacea in the waters off the coast of Azuero Peninsula in central Panama. These observations indicate the need for intensive surveys along this coast that in part may rely on key local informants to urgently implement conservation efforts for this species.

Diving behavior and energetic strategy of leatherback sea turtles during internesting intervals on St. Croix, U.S. Virgin Islands

Female leatherback sea turtles (Dermochelys coriacea; hereafter referred to as leatherbacks) nesting on St. Croix in the U.S. Virgin Islands in the spring lay 5–6 clutches, with an ~10-day internesting interval at sea between clutches. Although leatherbacks feed on gelatinous zooplankton during the winter, foraging and prey preference during the internesting interval has remained speculative. The goal of this study was to use miniature, animal-borne video and data recorders and satellite telemetry to monitor the diving behavior and movements of leatherbacks during the internesting interval on St. Croix. Our hypothesis was that foraging is rare and opportunistic during the internesting interval. Our results show that leatherbacks make two types of dives: Shallow Transit (ST) and Deep Transit (DT). ST dives were short (1.14 min), shallow (3.0 m). and associated with slow (0.6 m sec−1), subsurface swimming to reduce drag with no periods of gliding descent. DT dives were longer (13.42 min), deeper (84.0 m), and covered a 10-fold greater distance (446 m) than ST dives but at the same slow speed. The deepest and longest DT dive was 531 m in depth and 28.9 min in duration, but only 4% of DT dives were deeper than 200 m. Leatherbacks spent 94% of the time at sea making ST and DT dives with short resting periods at the surface. Six species of gelatinous prey were identified from recorded video, but feeding was rare and opportunistic indicating fasting during the nesting season. The estimated energy expended while at sea for five internesting trips over six weeks was equivalent to the catabolism of 28.2 kg of fat. An additional 12 kg of fat was needed for egg production, resulting in a total energy requirement equivalent to 40.2 kg of fat (~12% of body mass). Our results indicate that the purpose of the internesting interval is not foraging and that leatherbacks are capital breeders, which fast during the nesting season after acquiring energy reserves (i.e., fat) during the non-breeding season at higher latitudes where foraging effort may be more efficient.

Ontogenetic allometry underlies trophic diversity in sea turtles (Chelonioidea)

Despite only comprising seven species, extant sea turtles (Cheloniidae and Dermochelyidae) display great ecological diversity, with most species inhabiting a unique dietary niche as adults. This adult diversity is remarkable given that all species share the same dietary niche as juveniles. These ontogenetic shifts in diet, as well as a dramatic increase in body size, make sea turtles an excellent group to examine how morphological diversity arises by allometric processes and life habit specialisation. Using three-dimensional geometric morphometrics, we characterise ontogenetic allometry in the skulls of all seven species and evaluate variation in the context of phylogenetic history and diet. Among the sample, the olive ridley (Lepidochelys olivacea) has a seemingly average sea turtle skull shape and generalised diet, whereas the green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) show different extremes of snout shape associated with their modes of food gathering (grazing vs. grasping, respectively). Our ontogenetic findings corroborate previous suggestions that the skull of the leatherback (Dermochelys coriacea) is paedomorphic, having similar skull proportions to hatchlings of other sea turtle species and retaining a hatchling-like diet of relatively soft bodied organisms. The flatback sea turtle (Natator depressus) shows a similar but less extreme pattern. By contrast, the loggerhead sea turtle (Caretta caretta) shows a peramorphic signal associated with increased jaw muscle volumes that allow predation on hard shelled prey. The Kemp’s ridley (Lepidochelys kempii) has a peramorphic skull shape compared to its sister species the olive ridley, and a diet that includes harder prey items such as crabs. We suggest that diet may be a significant factor in driving skull shape differences among species. Although the small number of species limits statistical power, differences among skull shape, size, and diet are consistent with the hypothesis that shifts in allometric trajectory facilitated diversification in skull shape as observed in an increasing number of vertebrate groups.

Saving the sea turtles of Anguilla: Combining scientific data with community perspectives to inform policy decisions

Historic over-exploitation and the more recent threats caused by fisheries by-catch, disease and climate change have left sea turtle populations in the Wider Caribbean at risk of extinction. In 1995, following regional declines in nesting and foraging populations, the island of Anguilla implemented a moratorium on the hunting of turtles. At the request of the Government of Anguilla for scientific data to either support or remove the moratorium, comprehensive population estimates were obtained, and foraging, nesting and migratory movements were examined. In addition, community perspectives on turtles and their protection were assessed. Between 2015 and 18 surveys of 30 nesting beaches estimated low nesting activity with a maximum of 41 hawksbill, 15 green, and 1–2 leatherback turtles nesting in Anguilla annually. The inter-nesting range of hawksbills exhibited high levels of geographic overlap and occurred within 1.5 km of nesting beaches. Migratory tracks of hawksbill turtles traversed through seven exclusive economic zones, two of which allow a legal turtle fishery. Site fidelity was observed in foraging areas of green turtles and genetic analysis revealed population differentiation between green turtle foraging sites in Anguilla and between hawksbill rookeries in Anguilla compared to other Leeward Islands, indicating the individual importance of each foraging and nesting site. The Anguillan public (n = 302) overwhelmingly agreed with the current ban on harvesting sea turtles and considered turtles important for ecotourism. Our work provides a case-study, that can be applied globally, of how scientific research combined with community perspectives can effectively inform policy and ultimately protect endangered species, and highlights that local Governments provided with high quality data in a timely fashion for their policy making timetable are more likely to integrate findings into their decision-making process.

Ontogeny and ecological significance of metabolic rates in sea turtle hatchlings

BackgroundSea turtle hatchlings must avoid numerous predators during dispersal from their nesting beaches to foraging grounds. Hatchlings minimise time spent in predator-dense neritic waters by swimming almost continuously for approximately the first 24 h post-emergence, termed the ‘frenzy’. Post-frenzy, hatchling activity gradually declines as they swim in less predator-dense pelagic waters. It is well documented that hatchlings exhibit elevated metabolic rates during the frenzy to power their almost continuous swimming, but studies on post-frenzy MRs are sparse.ResultsWe measured the frenzy and post-frenzy oxygen consumption of hatchlings of five species of sea turtle at different activity levels and ages to compare the ontogeny of mass-specific hatchling metabolic rates. Maximal metabolic rates were always higher than resting metabolic rates, but metabolic rates during routine swimming resembled resting metabolic rates in leatherback turtle hatchlings during the frenzy and post-frenzy, and in loggerhead hatchlings during the post-frenzy. Crawling metabolic rates did not differ among species, but green turtles had the highest metabolic rates during frenzy and post-frenzy swimming.ConclusionsDifferences in metabolic rate reflect the varying dispersal stratagems of each species and have important implications for dispersal ability, yolk consumption and survival. Our results provide the foundations for links between the physiology and ecology of dispersal of sea turtles.

What type of plastic do sea turtles in Korean waters mainly ingest? Quantity, shape, color, size, polymer composition, and original usage

Globally, sea turtles are at high risk of ingesting plastic. However, research on plastic ingestion by sea turtles in East Asia is scant, and no quantitative or qualitative investigation has been conducted in Korean waters. This study examined the plastic ingestion of sea turtles stranded, floating, or incidentally captured in Korean waters between 2012 and 2018. The quantity, shape, color, size, polymer type, and original usage of plastic debris (>1 mm) ingested by sea turtles were analyzed after being sorted from the gastrointestinal tracts of 34 turtles (21 loggerheads (Caretta caretta), 9 green turtles (Chelonia mydas), 2 leatherbacks (Dermochelys coriacea), and 2 olive ridleys (Lepidochelys olivacea)). The ingestion frequencies of greens, loggerheads, olive ridleys, and leatherbacks were 100%, 81%, 50%, and 50%, respectively. The mean amount of plastic ingested was 108 ± 253 mg/kg (38 ± 61 n/ind.). The ingested debris tended to be films and fibers (>80%), light in color (white and transparent; 65%), and light polymers (polyethylene, polypropylene, polypropylene [poly (ethylene:propylene)], expanded polystyrene; 93%). The original uses were identified for 187 pieces; single-use plastics (e.g., plastic bag and packaging) and fishing and aquaculture items (e.g., twine and net) were found to dominate. Green turtles (264 ± 433 mg/kg) ingested significantly higher amounts of plastic than loggerheads (72.8 ± 156 mg/kg). Green turtles ingested mostly fibers (51%), such as rope, twine, and net, while loggerheads ingested largely films (61%), such as plastic bags and packaging. Interspecies differences in quantities and shapes of ingested debris may be related to their distinct feeding habits and geographical range of movement. The present study demonstrates that sea turtles foraging in Korean waters are considerably affected by marine plastic debris, and indicates that proper waste management of single-use plastics and fishing gears is urgently needed to mitigate the damage that plastic debris causes to marine wildlife.

Morphometrics and blood analytes of leatherback sea turtle hatchlings (Dermochelys coriacea) from Florida: reference intervals, temporal trends with clutch deposition date, and body size correlations.

The northwest Atlantic leatherback sea turtle (Dermochelys coriacea) population is exhibiting decreasing trends along numerous nesting beaches. Since population health and viability are inherently linked, it is important to establish species- and life-stage class-specific blood analyte reference intervals (RIs) so that effects of future disturbances on organismal health can be better understood. For hatchling leatherbacks, the objectives of this study were to (1) establish RIs for morphometrics and blood analytes; (2) evaluate correlations between hatchling morphometrics, blood analytes, and hatching success; and (3) determine temporal trends in hatchling morphometrics and blood analytes across nesting season. Blood samples were collected from 176 naturally emerging leatherback hatchlings from 18 clutches. Reference intervals were established for morphometrics and blood analytes. Negative relationships were noted between hatchling mass and packed cell volume, total white blood cells, heterophils, lymphocytes, and total protein and between body condition index (BCI) and immature red blood cells (RBC), RBC polychromasiaand anisocytosis, and total protein. Clutch deposition date showed positive relationships with lymphocytes and total protein, and negative relationships with hatchling mass and BCI. Hatching success was positively correlated with mass, and negatively with total protein and glucose, suggesting that nutritional provisions in eggs, incubation time, and/or metabolic rates could change later in the season and affect survivorship. These various observed correlations provide evidence for increased physiological stress (e.g., inflammation, subclinical dehydration) in hatchlings emerging later in nesting season, presumably due to increased nest temperatures or other environmental factors (e.g., moisture/rainfall). Data reported herein provide morphometric and blood analyte data for leatherback hatchlings and will allow for future investigations into spatiotemporal trends and responses to various stressors.

Seasonal factors affecting sea turtle nesting in the Southeastern Caribbean Sea (Gulf of Paria, Venezuela)

The nesting characteristics (number of nests and eggs, time of year, nesting initiation, and nesting length) of leatherback (Dermochelys coriacea) and hawksbill (Eretmochelys imbricata) sea turtles of the southern Caribbean Sea (specifically in the Gulf of Paria in Venezuela), were examined in association with weekly precipitation averages and number of rainy days per week during the period between 2009 and 2018. We hypothesized about the influence of rainfall intensity and patterns as the main abiotic factor for sea turtle nesting. On average, leatherbacks preferred nesting during the drier season of each year (March, April, and May), while hawksbills nested during the rainy season (June to September). For both species, we found few significant correlations between the number of nests or clutch size (number of eggs per nest) and weekly averages of seasonal precipitation rates in the region. Average hawksbill clutch sizes were not correlated with average precipitation rates but were positively correlated with the number of rainy days per week (r=0.66, P≤0.05). Average hawksbill clutch sizes decreased each year on average (-3.3 eggs/year, r=-0.88, P≤0.001), which coincided with a negative long-term trend in the number of rainy days (-0.11 rainy days/week, r=-0.69, P≤0.05). During the study period, nesting activities for both leatherback and hawksbills started progressively later (0.9 and 0.6 weeks/year, respectively p≤0.05) and were shorter (-0.9 and -0.8 weeks /year, P≤0.1 and P≤0.05, respectively).

Marine turtles and their barnacles from Scottish waters and adjacent seas

The history of marine turtles in Scottish waters and adjacent seas is reviewed. The recording and reporting schemes for stranded marine animals in Scotland and the U.K. are highlighted. Detailed descriptions are provided of strandings of a loggerhead turtle (Caretta caretta) at Irvine, Ayrshire in December 2015, with numerous attached goose barnacles (Lepas anatifera) and a leatherback turtle (Dermochelys coriacea) at St. Cyrus, Aberdeenshire in January 2016, with several acorn barnacles (Stomatolepas dermochelys). A review of U.K. marine animal strandings reports revealed additional records of L. anatifera and L. hillii, from stranded loggerheads in Carmarthenshire in 2006 and in Cornwall in 2016 respectively, as well as another leatherback with S. dermochelys in Cornwall in 2018. The occurrence of lepadomorph and balanomorph barnacles on turtles is discussed including historical records from the U.K. and Ireland, and adjacent waters in the Mediterranean and the north-east Atlantic. Taxonomic confusion within the genus Stomatolepas is clarified. Other species of barnacle that might occur on turtles reaching the waters of the U.K. and Ireland in the future are discussed along with other exotic fauna that can accompany turtles. The impact of barnacles on turtles and how turtles remove attached epibionts is summarised.

Sea turtle strandings and the importance of the restinga de Jurubatiba National Park in loggerhead (Caretta caretta) nesting sites

Protected areas represent important refuges for several species of fauna, mitigating human impacts and providing food resources and reproductive sites. In this study, analyzed the stranding pattern of sea turtles and the importance of the largest restinga protected area in Brazil, the Restinga de Jurubatiba National Park, Rio de Janeiro, Brazil, as a potential nesting site for Caretta caretta. A total of 352 strandings were recorded from October 2017 to September 2020 by direct monitoring on the beaches. The species with the highest recorded stranding was Chelonia mydas (n = 146), followed by Lepidochelys olivacea (n = 100), Caretta caretta (n = 91), Dermochelys coriacea (n = 11) and Eretmochelys imbricata (n = 4). The highest number of stranding records occurred in the end of winter and during spring. A total of 223 nests were registered, mostly in spring and summer, with most records of C. caretta nesting between November and December. The occurrence of nesting in the park area demonstrates it is importance for the conservation of sea turtles, since the lack of urbanization reduces anthropogenic impacts such as overfishing, egg collection, running over and artificial lighting, which favors that these animals complete their cycle of life.

Pan-oceanic distribution of mercury (Hg) in sea turtles: a review

With no known biological function, mercury (Hg) is highly toxic, bio-accumulates, and biomagnifies up the food web. Long-living marine animals, such as sea turtles, can be exposed to Hg in the oceans. The wide distributions of these reptiles and lifespans compatible with Hg residence time in ocean surface waters (approximately 30 yr) makes them reliable biological monitors of the long-term changes in Hg concentrations in the oceans. Taking this into consideration, we conducted a thorough review of studies to compare the concentrations of Hg in the 7 species of sea turtles distributed in different regions of the Atlantic, Pacific, and Indian Oceans and the Mediterranean Sea. Hg concentrations in muscle and scutes of Chelonia mydas were highest in the South Atlantic, whereas the highest concentrations found in Caretta caretta occurred in the Mediterranean Sea. The differences could be associated with the feeding habits of each species and the characteristics of the environment, such as the oligotrophic nature of the water and the lower productivity in the Mediterranean Sea. Unfortunately, few studies exist for the other 5 sea turtles (Dermochelys coriacea, Eretmochelys imbricata, Lepidochelys olivacea, L. kempii, and Natator depressus), which hampers a more detailed regional or ecological comparison among species. The results found in this review reveal information gaps that should be filled through more numerous studies focused on different oceanic regions and species.

Sea Turtle Nesting: What Is Known and What Are the Challenges under a Changing Climate Scenario

The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival; especially temperature increase, which is particularly fast, impacts life history characteristics, such as temperature-dependent sex determination (TSD), late maturity and sea turtles highly migratory nature. This review aims to identify and summarize the information that has been collected from 2009-2020 in order to aid future empirical studies that seek to fill these and other knowledge gaps, and subsequently assist conservationists in making multilevel decisions to protect sea turtle populations and species. In a summarized way the general knowledge acquired so far on the influence of environmental abiotic and biotic factors on nesting behaviour and hatching, emergence and survival successes of sea turtle hatchlings, was gathered. To accomplish this work, a search on Web of Science, Science Direct, NCBI/PubMed, and Google Scholar was carried out using the terms “sea turtles + climate change”. Published articles in the period 2009-2020 were selected, related to the nesting ecology of 5 species of sea turtles: Caretta caretta, Eretmochelys imbricata, Dermochelys coriacea, Chelonia mydas, Lepidochelys olivacea. Emphasis was also placed on geographical information and on population location (e.g. climatic conditions during the nesting season). These articles (N = 126) were analysed giving relevance to researcher’s data interpretations, comparisons with other researches, and the reached conclusions. An attempt was made to represent all 5 species of sea turtles when selecting articles on each of the environmental factors that influence sea turtle nesting: temperature, humidity, nesting substrate, gases, depth of the nest, sea surface temperature (SST), nest location on the beach, nesting phenology and geographic distribution of nesting habitats. The interaction between these parameters and their consequences on the terrestrial phase of reproduction are presented and discussed.

The Leatherback Turtle (Dermochelys Coriacea) and Plastics in the Northwest Atlantic Ocean: A Hazard Assessment

The Leatherback Turtle (Dermochelys Coriacea) and Plastics in the Northwest Atlantic Ocean: A Hazard Assessment