Juvenile Green Turtles Research Articles

The effect of diet on the gastrointestinal microbiome of juvenile rehabilitating green turtles (Chelonia mydas).

Threatened and endangered green turtles (Chelonia mydas) are unique because as juveniles they recruit from pelagic to near-shore waters and shift from an omnivorous to primarily herbivorous diet (i.e. seagrass and algae). Nevertheless, when injured and ill animals are admitted to rehabilitation, animal protein (e.g. seafood) is often offered to combat poor appetite and emaciation. We examined how the fecal microbiome of juvenile green turtles changed in response to a dietary shift during rehabilitation. We collected fecal samples from January 2014 –January 2016 from turtles (N = 17) in rehabilitation at the Georgia Sea Turtle Center and used next generation sequencing to analyze bacterial community composition. Samples were collected at admission, mid-rehabilitation, and recovery, which entailed a shift from a mixed seafood–vegetable diet at admission to a primarily herbivorous diet at recovery. The dominant phyla changed over time, from primarily Firmicutes (55.0%) with less Bacteroidetes (11.4%) at admission, to primarily Bacteroidetes (38.4%) and less Firmicutes (31.8%) at recovery. While the microbiome likely shifts with the changing health status of individuals, this consistent inversion of Bacteroidetes and Firmicutes among individuals likely reflects the increased need for protein digestion, for which Bacteroidetes are important. Firmicutes are significant in metabolizing plant polysaccharides; thus, fewer Firmicutes may result in underutilization of wild diet items in released individuals. This study demonstrates the importance of transitioning rehabilitating green turtles to an herbivorous diet as soon as possible to afford them the best probability of survival.

Contrasted habitats and individual plasticity drive the fine scale movements of juvenile green turtles in coastal ecosystems

BackgroundA strong behavioural plasticity is commonly evidenced in the movements of marine megafauna species, and it might be related to an adaptation to local conditions of the habitat. One way to investigate such behavioural plasticity is to satellite track a large number of individuals from contrasting foraging grounds, but despite recent advances in satellite telemetry techniques, such studies are still very limited in sea turtles.MethodsFrom 2010 to 2018, 49 juvenile green turtles were satellite tracked from five contrasting feeding grounds located in the South-West Indian Ocean in order to (1) assess the diel patterns in their movements, (2) investigate the inter-individual and inter-site variability, and (3) explore the drivers of their daily movements using both static (habitat type and bathymetry) and dynamic variables (daily and tidal cycles).ResultsDespite similarities observed in four feeding grounds (a diel pattern with a decreased distance to shore and smaller home ranges at night), contrasted habitats (e.g. mangrove, reef flat, fore-reef, terrace) associated with different resources (coral, seagrass, algae) were used in each island.ConclusionsJuvenile green turtles in the South-West Indian Ocean show different responses to contrasting environmental conditions - both natural (habitat type and tidal cycle) and anthropogenic (urbanised vs. uninhabited island) demonstrating the ability to adapt to modification of habitat.

Behavioral effects of scents from male mature Rathke glands on juvenile green sea turtles (Chelonia mydas).

Sea turtles can detect airborne and waterborne odors, but whether they recognize scents from the same species and if so, how they affect their behavior remains unknown. The present study evaluated the behavioral effects of odorants on juvenile green sea turtles (Chelonia mydas). The odorants were derived from Rathke glands (external scent glands) of mature male green sea turtles, and from two types of food. The activity of the juveniles increased when exposed to food scents, and significantly decreased compared with controls when exposed to scents from Rathke glands. These findings indicated that scents from the same species affect behavior, and that chemical communication via olfaction has important outcomes for sea turtles.

Plasma cholinesterase activity as an environmental impact biomarker in juvenile green turtles (Chelonia mydas)

ABSTRACT: The objective of this study was to evaluate the enzymatic activity of plasma cholinesterase in Chelonia mydas marine turtles belonging to two populations, according to their capture sites, under the absence and probable influence of anthropic effects. A total of 74 animals were used and later divided into two groups, based on the capture site. Blood samples were collected from all captured animals, which were then released into the sea at the site of capture. A descriptive statistical analysis of the plasma cholinesterase activity values and an analysis comparing these values based on the capture site were performed. Samples of heparinized plasma from animals captured at the two different sites were analyzed. Plasma cholinesterase activity ranged from 121 to 248U/L, with a mean and standard deviation of 186.1±30.68U/L. When comparing plasma cholinesterase activity values in individuals based on the capture site, a significant difference was observed. Establishing reference values for different sea turtle populations is necessary to interpret future sampling results and to allow sea turtles to be used as sentinels of ecosystem health. Future studies are needed to evaluate other populations and the activity of plasma cholinesterase in juvenile marine turtles, in relation to environmental contamination.

Health assessment of juvenile green turtles in southern São Paulo State, Brazil: a hematologic approach.

We assessed the health status and hematologic and blood chemistry values of 48 juvenile green turtles (Chelonia mydas) on the southeastern coast of Brazil (25°S 48°W). We investigated the impact of size and weight, nutritional condition, and presence of epibionts and fibropapilloma tumors. Nutritional status was good for 39 animals; these animals had higher serum albumin, cholesterol, and phosphorus concentrations than 9 animals with a fair nutritional score. Reference values for hematology and biochemistry were calculated for 39 individuals without fibropapillomas (FPs). Turtles with epibionts (n = 33) had lower hemoglobin (Hb) than turtles without epibionts (n = 15; t = -2.09, p = 0.04), and the area occupied by epibionts was positively correlated with the white blood cell count (r = 0.37, p = 0.03). FP turtles had significantly lower hematocrit (Hct), Hb, and red blood cell (RBC) counts than non-FP turtles; serum albumin and cholesterol were higher in non-FP than FP turtles. A negative correlation between curved carapace length (CCL) and Hct (r = -0.51, p = 0.0002) and RBC (r = -0.47, p = 0.0007), and between serum cholesterol, sodium, and uric acid and CCL (r = -0.53, p = 0.0001; r = -0.38, p = 0.007; r = -0.35, p = 0.014, respectively) were identified. The health of turtles appears to deteriorate as they get larger, which manifests in more FPs, decreased body condition, and systemic physiologic changes consistent with chronic disease including lower Hct, RBC counts, serum cholesterol, sodium, and uric acid.

Discovery of the first feeding area for adult and juvenile green turtles and loggerhead turtles in Greece

Discovery of the first feeding area for adult and juvenile green turtles and loggerhead turtles in Greece

Acoustic tag retention rate varies between juvenile green and hawksbill sea turtles

BackgroundBiotelemetry has become a key tool for studying marine animals in the last decade, and a wide range of electronic tags are now available for answering a range of research questions. However, comparatively, less attention has been given to attachment methods for these tags and the implications of tag retention on study design, especially when designing a comparative study looking at multiple species. Here, we reported our findings on acoustic tag retention rates for juveniles of two species of marine turtle: the green sea turtle (Chelonia mydas) and the hawksbill sea turtle (Eretmochelys imbricata). We captured both species twice annually (spring and fall) from 2012 through 2017, as part of a capture–mark–recapture study at Buck Island Reef National Monument, St. Croix, U.S. Virgin Islands. We assessed tag retention rates using physical recaptures of turtles previously outfitted with an acoustic tag.ResultsWe deployed 72 acoustic tags on 60 juvenile greens and 37 acoustic tags on 29 hawksbills. We estimated the half-life for tags on greens to be 150 days (95% CI 117–188 days), whereas the half-life for tags on hawksbills was 1077 days (95% CI 870–2118 days), a marked difference. We observed that tag attachment holes, drilled into the posterior marginal scutes, migrated laterally towards the outer edge of the marginals in both species. Green turtles tended to exhibit tear-outs, as their attachment holes wore and/or tags grew near the edge of their scutes, whereas hawksbills tended to maintain the structure of these holes and did not exhibit these tear-outs.ConclusionsWe conclude that hawksbills can be tagged with long-battery-life acoustic tags for long-term studies of habitat use and movement patterns, whereas greens are likely to shed their tags in the 1st year, making long-term studies difficult. This study is the first clear evidence that tagging protocols should vary between species of hard-shelled turtles. Furthermore, shed tags on the seafloor continue to be detected by acoustic receivers, creating a challenge in data filtering before analysis. We encourage future research into an efficient method for filtering these data points prior to analysis.

Fatal Rameshwarotrema uterocrescens infection with ulcerative esophagitis and intravascular dissemination in green turtles.

The trematode Rameshwarotrema uterocrescens (Digenea: Pronocephalidae) parasitizes the glands of the caudal esophagus of Chelonia mydas. In the present study, 741 C. mydas were examined, 85 animals had adult specimens of R. uterocrescens associated with necrotizing ulcerous esophagitis, of these 85, 21 presented invasion of the esophageal mural vessels in the caudal esophagus of juvenile green turtles (Chelonia mydas). Necrotizing granulomatous splenitis, hepatitis, and nephritis were associated with the presence of parasites. The eggs from R. uterocrescens are birefringent under plane-polarized light, which distinguishes them from those of spirorchiid trematodes. This study contributes novel data on R. uterocrescens, methods for detecting this parasite, and demonstrates the fatal potential of parasitism in C. mydas.

Bacteriophage versus antibiotic therapy on gut bacterial communities of juvenile green turtle, Chelonia mydas.

Green turtles are endangered marine herbivorous hindgut fermenters that contribute to a variety of marine ecosystems. Debilitated turtles are often rehabilitated in turtle hospitals. Since accurate diagnosis of disease is difficult, broad-spectrum antibiotics are routinely used as a general treatment, potentially causing collateral damage to the gut microbiome of the patient. Here, we evaluated the concept of the application of bacteriophage (phages) to eliminate targeted intestinal bacteria as an alternative to a broad-spectrum antibiotic (enrofloxacin) in clinically healthy, captive green turtles. Additionally, the impact of a broad-spectrum antibiotic (enrofloxacin) and phage therapy on the gut bacterial communities of green turtles was evaluated. Gut bacterial communities in faecal samples were analysed by sequencing the V1-V3 regions of the bacterial 16S rRNA. Bacteria-specific phage cocktails significantly (P < 0.05) reduced targeted Acinetobacter in phage-treated turtles during the therapy. Compared to control, no significant difference was observed in the bacterial diversity and compositions in phage-treated turtles. In contrast, bacterial diversity was significantly (P < 0.05) reduced in antibiotic-treated turtles at day 15 and throughout the trial. The alteration in the bacterial microbiota of antibiotic-treated turtles was largely due to an increase in abundance of Gram-positive Firmicutes and a concurrent decrease in Gram-negative Bacteroidetes, Proteobacteria and Verrucomicrobia. Additionally, we observed the relative abundance of several bacteria at lower taxonomic level was much less affected by phages than by antibiotics. These data offer the proof of concept of phage therapy to manipulate transient as well as indigenous bacterial flora in gut-related dysbiosis of turtles.

The Genus Rhytidodoides Price, 1939 (Digenea: Rhytidodidae) in Brazil: New Geographic Occurrence and Report of Pathology in the Gallbladder.

SummaryThe present note describes the occurrence of Rhytidodoides intestinalis and Rhytidodoides similis (Digenea: Rhytidodidae) in the gallbladder of two juvenile green turtles (Chelonia mydas - Testudines, Cheloniidae) found on the coast of Brazil. Both were detected in gallbladder and intestine of green turtles: Rhytidodoides similis (United States, Panama, Costa Rica and Brazil) and R. intestinais (United States, Panama and Costa Rica). This note is the first report of R. intestinalis in Brazil and South-West Atlantic Ocean. Also the histological lesions caused by the parasites in one gallbladder are described.

Individual variability in the settlement of juvenile green turtles in the western South Atlantic Ocean: relevance of currents and somatic growth rate

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 614:173-182 (2019) - DOI: https://doi.org/10.3354/meps12909 Individual variability in the settlement of juvenile green turtles in the western South Atlantic Ocean: relevance of currents and somatic growth rate Patricia Campos, Luis Cardona* IRBio and Department of Evolutionary Biology, Ecology and Environmental Science, Faculty of Biology, University of Barcelona, Avenida Diagonal 643, 08028 Barcelona, Spain *Corresponding author: luis.cardona@ub.edu ABSTRACT: The settlement of demersal animals is influenced both by physical processes ruling the distribution of pelagic juveniles in the open ocean and by their active selection of suitable benthic habitats. Green turtles Chelonia mydas inhabiting the coastal areas of the western South Atlantic Ocean derive primarily from the rookery at Ascension Island and settle over a huge area spanning from northern Brazil to Uruguay. Here, we analysed the stable C and N isotope ratios in 30 µm of carapace layers from juvenile green turtles collected from 2 distinct areas of Brazil (Praia do Forte, 12°38’S, 38°05’W, and Ubatuba, 23°26’S, 45°05’W), with the goal of reconstructing their individual diets and habitat use patterns. Juvenile neritic green turtles from Praia do Forte usually had herbivorous diets, with limited individual variability and few temporal changes in diet or habitat. Conversely, most juvenile green turtles from Ubatuba had omnivorous diets, although they exhibited high levels of individual and temporal variability. These contrasting patterns could be linked to less abundant and predictable food availability in subtropical Ubatuba compared to tropical Praia do Forte. It is unknown why large numbers of juvenile green turtles bypass foraging grounds in north-eastern Brazil to settle in subtropical or warm temperate areas, although it may be related to individual differences in growth rate and their size being too small when reaching Brazil from Ascension Island. KEY WORDS: Juvenile turtles · Chelonia mydas · Settlement · Developmental habitat · Stable isotopes Full text in pdf format PreviousNextCite this article as: Campos P, Cardona L (2019) Individual variability in the settlement of juvenile green turtles in the western South Atlantic Ocean: relevance of currents and somatic growth rate. Mar Ecol Prog Ser 614:173-182. https://doi.org/10.3354/meps12909 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 614. Online publication date: April 04, 2019 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2019 Inter-Research.

Habitat Use and Behavior of Multiple Species of Marine Turtles at a Foraging Area in the Northeastern Gulf of Mexico

Multi-species conservation strategies can be useful to maximize allocation of resources. To effectively plan for multi-species management practices, it is important to have a robust understanding of the variability in the spatial and behavioral ecology of sympatric species. To address this in the context of marine turtles, this study explored fine-scale habitat use by three sympatric species (juvenile green turtles (Chelonia mydas), Kemp’s ridley turtles (Lepidochelys kempii) and loggerhead turtles (Caretta caretta)) in a foraging area near Crystal River, Florida, USA. By combining sighting surveys and satellite tracking methods, we found that the distribution of the three species of marine turtles in this region overlapped both in space and time. We also observed differences in the fine-scale location of hotspots and in-water behavior among species, with some degree of apparent habitat partitioning. Habitat partitioning was particularly evident when assessing the diving and surfacing behavior of tracked turtles, with some degree of differentiation in diel diving patterns, particularly depths utilized during daytime/nighttime and the dive/surface duration. Our study provides ecological baseline data on the spatial overlap, habitat use and behavior of three sympatric marine turtle species, which can inform future management strategies at nearshore marine habitats in the Northeastern Gulf of Mexico.

Hg and δ15N in juvenile green turtles from southeastern Brazil (~23°S): Inferences about contamination levels and recruitment to coastal waters

Total mercury (THg) and δ15N were analysed in liver and muscle of juvenile green turtles (Chelonia mydas) from a foraging site in southeastern Brazil (~23°S) to evaluate contamination levels and make inferences about the timescale that animals were recruited from oceanic to coastal waters. The values for THg and δ15N in liver and muscle were 432.2 and 72.8 μg kg−1 and 10.0‰ and 9.2‰, respectively. THg concentrations in tissues indirectly indicated that the main food resources for this consumer (i.e., macroalgae) had negligible levels of this element. Thus, this foraging site could be considered a pristine area in terms of Hg contamination. The THg and δ15N in liver were derived by more recent food ingestion than those in muscle. The juvenile green turtles that died because of incidental captures in fisheries practiced along this foraging site were individuals newly recruited from oceanic waters.

Mixed stock analysis of juvenile green turtles aggregating at two foraging grounds in Fiji reveals major contribution from the American Samoa Management Unit

In this study we assessed the breeding population, or Management Unit (MU), origin of green turtles (Chelonia mydas) present at Yadua Island and Makogai Island foraging grounds in Fiji, central South Pacific. Based on analysis of mitochondrial (mt) DNA sequences from 150 immature green turtles caught during surveys carried out in 2015–2016, we identified a total of 18 haplotypes, the most common being CmP22.1 (44%) which is a primary haplotype characterizing the American Samoa breeding population. Results of a Bayesian mixed-stock analysis reveals that the two foraging grounds are used by green turtles from the American Samoa MU (72%, Credible Interval (CI): 56–87%), New Caledonia MU (17%, CI: 6–26%) and French Polynesia MU (7%, CI: 0–23%). The prominence of the contribution we found from the American Samoa MU compared to that of French Polynesia, both which have historic telemetry and tagging data showing connectivity with Fijian foraging areas, may reflect the current relative abundance of these two nesting populations and draws attention to a need to update population surveys and identify any significant nesting in Fiji that may have been overlooked.

Diverse foraging habits of juvenile green turtles (Chelonia mydas) in a summer-restricted foraging habitat in the northwest Pacific Ocean

Green turtles in year-round neritic foraging habitats are widely considered to have small home ranges and to mainly feed on plant-based diets. In contrast, few studies have examined the summer-restricted habitats to which these turtles seasonally migrate. In this study, we investigated the foraging habits of green turtles migrating to the Sanriku Coast, a summer-restricted foraging habitat in a temperate area (38–39°N) of the northwest Pacific Ocean, using stable isotope analysis and biologging experiments from 2007 to 2015. Stable isotope analysis (n = 40, straight carapace length (SCL): 36.8–90.9 cm) indicated that most of the turtles, especially all smaller turtles (n = 35, SCL < 58 cm), relied on gelatinous prey before arriving at the Sanriku Coast. According to the biologging experiments (451.2 h of behavioral data and 43.2 h of video data, n = 6, SCL: 44.5–81.0 cm), the turtles shifted their main food to macro-algae (135 out of 148 feeding events) and consumed it at the sea bottom during their stay in the specific localized area of the Sanriku Coast. However, the turtles still consumed gelatinous prey in midwater during their movement to other locations along the Sanriku Coast and/or during their migration to southern overwintering habitats (13 events). These results indicated that green turtles migrating to the Sanriku Coast exhibit dietary diversity relative to year-round habitats, and the turtles in this area seem to consume gelatinous prey during the transit period in addition to feeding on macro-algae during the resident period.

Fine scale geographic residence and annual primary production drive body condition of wild immature green turtles (Chelonia mydas) in Martinique Island (Lesser Antilles).

ABSTRACTThe change of animal biometrics (body mass and body size) can reveal important information about their living environment as well as determine the survival potential and reproductive success of individuals and thus the persistence of populations. However, weighing individuals like marine turtles in the field presents important logistical difficulties. In this context, estimating body mass (BM) based on body size is a crucial issue. Furthermore, the determinants of the variability of the parameters for this relationship can provide information about the quality of the environment and the manner in which individuals exploit the available resources. This is of particular importance in young individuals where growth quality might be a determinant of adult fitness. Our study aimed to validate the use of different body measurements to estimate BM, which can be difficult to obtain in the field, and explore the determinants of the relationship between BM and size in juvenile green turtles. Juvenile green turtles were caught, measured, and weighed over 6 years (2011–2012; 2015–2018) at six bays to the west of Martinique Island (Lesser Antilles). Using different datasets from this global database, we were able to show that the BM of individuals can be predicted from body measurements with an error of less than 2%. We built several datasets including different morphological and time-location information to test the accuracy of the mass prediction. We show a yearly and north–south pattern for the relationship between BM and body measurements. The year effect for the relationship of BM and size is strongly correlated with net primary production but not with sea surface temperature or cyclonic events. We also found that if the bay locations and year effects were removed from the analysis, the mass prediction degraded slightly but was still less than 3% on average. Further investigations of the feeding habitats in Martinique turtles are still needed to better understand these effects and to link them with geographic and oceanographic conditions.

Mass sea turtle slaughter at Pulau Tiga, Malaysia: Genetic studies indicate poaching locations and its potential effects

It is important to identify the location of illegal poaching and its effects on the conservation of endangered species. This study applied molecular techniques to estimate the origin of sea turtle carcasses (N = 53) found at Pulau Tiga, Kudat, Malaysia (Borneo) in 2014. All carcasses were of adult (77%) and large juvenile (23%) green turtles (Chelonia mydas). A total of 10 haplotypes of mitochondrial DNA were identified. A Bayesian mixed-stock analysis showed that the natal origin was mainly from the Sulu and Celebes Seas (uninformative prior: median = 53.0%, 95% credible interval [CI] = 34.5–76.9%; informative prior: median = 61.3%, CI = 36.9–89.4%). The estimation of source foraging grounds of the carcasses as poaching sites indicated the Brunei Bay in the South China Sea as the most probable source (median = 90.2%, CI = 11.2–99.9%), although caution is needed since there is a possibility of poaching at unsampled foraging grounds. The results indicate that such poaching has negative effects especially for the nesting populations at the Sulu and Celebes Seas. This study provides information that contributes to the development of measures against poaching activities by regional collaboration regarding sea turtle traffic and law enforcement in Southeast Asia.

Biphasic allometric growth in juvenile green turtles Chelonia mydas

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 37:301-308 (2018) - DOI: https://doi.org/10.3354/esr00930 Biphasic allometric growth in juvenile green turtles Chelonia mydas Michael Salmon1,*, Cody R. Mott2, Michael J. Bresette2 1Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida, 33431, USA 2Inwater Research Group, Jensen Beach, Florida 34957, USA *Corresponding author: salmon@fau.edu ABSTRACT: Green turtles raised in the laboratory widen faster than they lengthen, thus changing in shape from the proportions they show as hatchlings. By doing so, young turtles may sooner achieve a size refuge from their gape-limited predators. In this study, we document that wild juveniles captured at open-water weed lines in the Gulf of Mexico show similarly wider proportions, demonstrating for the first time that this growth pattern occurs in nature. We additionally quantified the shell dimensions of older juveniles that had abandoned weed lines and returned to occupy shallow coastal reefs. Those turtles exhibited a narrower ’hatchling like’ body shape. We conclude that juvenile green turtles show a biphasic pattern of initial widening, followed later by a secondary narrowing once they achieve a size that exceeds 25-30 cm in straight-line carapace length. We hypothesize that secondary narrowing may be advantageous for reducing lethal interactions with a different subset of larger predators, those that typically dismember their prey rather than swallow them whole. Finally, we categorize this complex growth pattern as one of several vulnerability traits that promote juvenile turtle survival, and document that they are expressed in different combinations among other marine turtle species. KEY WORDS: Allometric growth · Evolution · Predator-prey · Sea turtle · Vulnerability traits Full text in pdf format PreviousCite this article as: Salmon M, Mott CR, Bresette MJ (2018) Biphasic allometric growth in juvenile green turtles Chelonia mydas. Endang Species Res 37:301-308. https://doi.org/10.3354/esr00930 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 37. Online publication date: December 13, 2018 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2018 Inter-Research.

Connecting paths between juvenile and adult habitats in the Atlantic green turtle using genetics and satellite tracking.

Although it is commonly assumed that female sea turtles always return to the beach they hatched, the pathways they use during the years preceding their first reproduction and their natal origins are most often unknown, as it is the case for juvenile green turtles found in Martinique waters in the Caribbean. Given the oceanic circulation of the Guiana current flowing toward Martinique and the presence of important nesting sites for this species in Suriname and French Guiana, we may assume that a large proportion of the juvenile green turtles found in Martinique are originating from the Suriname–French Guiana beaches. To confirm this hypothesis, we performed mixed stock analysis (MSA) on 40 green turtles sampled in Martinique Island and satellite tracked 31 juvenile green turtles tagged in Martinique to (a) assess their natal origin and (b) identify their destination. Our results from MSA confirm that these juveniles are descendant from females laying on several Caribbean and Atlantic beaches, mostly from Suriname and French Guiana, but also from more southern Brazilian beaches. These results were confirmed by the tracking data as the 10 turtles leaving Martinique headed across the Caribbean–Atlantic region in six different directions and 50% of these turtles reached the Brazilian foraging grounds used by the adult green turtles coming from French Guiana. One turtle left the French Guianan coast to perform the first transatlantic migration ever recorded in juvenile green turtles, swimming toward Guinea‐Bissau, which is the most important nesting site for green turtles along the African coast. The extensive movements of the migrant turtles evidenced the crossing of international waters and more than 25 exclusive economic zones, reinforcing the need for an international cooperative network to ensure the conservation of future breeders in this endangered species.

Informing marine protected areas in Bimini, Bahamas by considering hotspots for green turtles (Chelonia mydas)

Knowledge on the spatial distribution, habitat use and processes of site selection by marine turtles is fundamental to identify key habitats, critical resources, and discrete foraging aggregations for protection. This is particularly important for regions of known importance for marine turtles and where widespread habitat degradation is taking place. The waters surrounding Bimini, Bahamas, provide important foraging areas for threatened juvenile green turtles (Chelonia mydas) however, these habitats are being severely degraded by coastal development. To inform managers on the design of planned future no-take marine protected areas (MPA) in Bimini, we used a spatial planning approach and incorporated diverse methodologies (e.g., visual surveys, capture events, passive acoustic telemetry) to identify areas of high use by juvenile green turtles. We also assessed forage items to understand habitat use by green turtles. This information was compared with how various stakeholders use the local waters to identify priority areas for protection within Bimini to maximize conservation of green turtles, while minimizing impact to society, and to meet the conservation target previously stipulated by government officials. Two regions within Bimini (South Flats in south Bimini and Bonefish Hole on the north Island) were identified as important areas for protection and suggestions are made on their considerations for MPA implementation.