Journal articles: 'Leatherback turtle Leatherback turtle Sea turtles'

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Báez, José C., David Macías, Salvador García-Barcelona, and Raimundo Real. "Interannual Differences for Sea Turtles Bycatch in Spanish Longliners from Western Mediterranean Sea." Scientific World Journal 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/861396.

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Recent studies showed that regional abundance of loggerhead and leatherback turtles could oscillate interannually according to oceanographic and climatic conditions. The Western Mediterranean is an important fishing area for the Spanish drifting longline fleet, which mainly targets swordfish, bluefin tuna, and albacore. Due to the spatial overlapping in fishing activity and turtle distribution, there is an increasing sea turtle conservation concern. The main goal of this study is to analyse the interannual bycatch of loggerhead and leatherback turtles by the Spanish Mediterranean longline fishery and to test the relationship between the total turtle by-catch of this fishery and the North Atlantic Oscillation (NAO). During the 14 years covered in this study, the number of sea turtle bycatches was 3,940 loggerhead turtles and 8 leatherback turtles, 0.499 loggerhead turtles/1000 hooks and 0.001014 leatherback turtles/1000 hooks. In the case of the loggerhead turtle the positive phase of the NAO favours an increase of loggerhead turtles in the Western Mediterranean Sea. However, in the case of leatherback turtle the negative phase of the NAO favours the presence of leatherback turtle. This contraposition could be related to the different ecophysiological response of both species during their migration cycle.

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Belmahi, Alae Eddine, Youcef Belmahi, Mouloud Benabdi, Amaria Latefa Bouziani, Samira Ait Darna, Yahia Bouslah, Mohamed Bendoula, and Mohamed Bouderbala. "First study of sea turtle strandings in Algeria (western Mediterranean) and associated threats: 2016–2017." Herpetozoa 33 (May 28, 2020): 113–20. http://dx.doi.org/10.3897/herpetozoa.33.e48541.

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Between December 2015 and December 2017 a total of 63 sea turtles were recorded as being stranded along the Algerian coast. The loggerhead sea turtle Caretta caretta was the most commonly stranded species (n = 44) (69.8%), followed by the leatherback Dermochelys coriacea (n = 18) (28.6%) and the green turtle Chelonia mydas (n = 1). There was a slight dominance of the adult size class for stranded loggerhead turtles, while, for the leatherback, late juveniles and adults prevailed. Most loggerhead turtles stranded during the summer months (July and August), whereas most leatherbacks stranded during winter. The breakdown of the strandings by region shows a slight dominance along the western and central shores for C. caretta and a clear dominance in the west for D. coriacea. The primary cause of death was determined in 50.8% of the stranded turtles. Regarding the evidence of interactions with humans the major cause of stranding in loggerhead turtles was incidental catch by artisanal fisheries, followed by boats’ collisions. The main causes of leatherback strandings were boats’ collisions. Algerian data show that human activities affect loggerhead turtles and also prove a significant presence of the leatherback turtle on this coast.

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Robinson, Nathan J., Eric A. Lazo-Wasem, Frank V. Paladino, John D. Zardus, and Theodora Pinou. "Assortative epibiosis of leatherback, olive ridley and green sea turtles in the Eastern Tropical Pacific." Journal of the Marine Biological Association of the United Kingdom 97, no. 6 (May 19, 2016): 1233–40. http://dx.doi.org/10.1017/s0025315416000734.

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Sea turtles host a diverse array of epibionts, yet it is not well understood what factors influence epibiont community composition. To test whether epibiont communities of sea turtles are influenced by the hosts’ nesting or foraging habitats, we characterized the epibiota of leatherback, olive ridley and green turtles nesting at a single location on the Pacific coast of Costa Rica. We also compared the epibiota of these turtles to conspecific populations nesting elsewhere in the East Pacific. If epibiont communities are influenced by nesting habitats, we predicted that sympatrically nesting turtles would have comparable epibiont taxa. Alternatively, if epibiont communities are influenced by foraging habitats, we predicted the diversity of epibiont taxa should reflect the type and diversity of the hosts’ foraging habitats. We identified 18 epibiont taxa from 18 leatherback, 19 olive ridley and six green turtles. Epibiont diversity was low on leatherbacks (four taxa), but higher for olive ridley and green turtles (12 and nine epibiont taxa respectively). The epibiont communities of olive ridley and green turtles were not statistically different, but both were different from leatherbacks. In addition, conspecific sea turtles from other nesting locations hosted more similar epibiont communities than sympatrically nesting, non-conspecifics. We conclude that epibiont diversity of nesting sea turtles is partially linked to the diversity of their foraging habitats. We also conclude that the surface properties of the skin and carapace of these turtles may contribute to the uniqueness of leatherback turtle epibiont communities and the similarities between olive ridley and green turtle epibiont communities.

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Godfrey, Matthew H., N. Mrosovsky, and R. Barreto. "Estimating past and present sex ratios of sea turtles in Suriname." Canadian Journal of Zoology 74, no. 2 (February 1, 1996): 267–77. http://dx.doi.org/10.1139/z96-033.

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Leatherback (Dermochelys coriacea) and green (Chelonia mydas) sea turtles in Suriname lay eggs over several months of the year. During this nesting season, changes in rainfall produce changes in sand temperature, which in turn influence the sexual differentiation of incubating sea turtle embryos. The overall sex ratio of leatherback and green sea turtle hatchlings produced at Matapica beach in Suriname was investigated. Estimates of the sex ratios of these turtles in 1993 (green turtles 63.8% female, leatherbacks 69.4% female) were roughly 10% more female-biased than those from an earlier study in 1982. For both species, a significant negative relationship was found between monthly rainfall and monthly sex ratios. Using this relationship and data on rainfall in the past, it was possible to estimate overall sex ratios for an additional 12 years. These estimates varied considerably among different years, ranging from 20 to 90% female in the case of green turtles. Nevertheless, males tended to be produced primarily in April and May, while some females were produced in all months. Such seasonal patterns of production of turtles of different sexes have implications for sea turtle conservation programs that involve manipulating or harvesting eggs.

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Weir, Caroline R., Tamar Ron, Miguel Morais, and Agostinho Domingos C. Duarte. "Nesting and at-sea distribution of marine turtles in Angola, West Africa, 2000–2006: occurrence, threats and conservation implications." Oryx 41, no. 2 (April 2007): 224–31. http://dx.doi.org/10.1017/s003060530700186x.

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AbstractThe status of marine turtles in Angola, West Africa, is poorly known, and therefore during 2000–2006 a combination of both dedicated and opportunistic beach and at-sea turtle surveys were carried out, and interviews conducted with fishing communities and at markets. Green Chelonia mydas, olive ridley Lepidochelys olivacea, leatherback Dermochelys coriacea and loggerhead turtles Caretta caretta were recorded, and nesting of the first three species confirmed during September–March (peaking November–December). Green turtles nested mainly in the south, leatherback turtles in north and central Angola, and olive ridley turtle nesting was widespread. Olive ridley turtle nest density at Palmeirinhas averaged 32 nests km−1. At-sea surveys produced 298 turtle records, with peak occurrence during August. Significant anthropogenic-related mortality (including exploitation of meat and eggs and fishing bycatch) was recorded, in addition to natural predation and other threats. Maintenance of the long-term sustainability of these turtle populations should focus on the involvement of fishing communities and increasing awareness throughout Angola.

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James, Michael C., and N. Mrosovsky. "Body temperatures of leatherback turtles (Dermochelys coriacea) in temperate waters off Nova Scotia, Canada." Canadian Journal of Zoology 82, no. 8 (August 1, 2004): 1302–6. http://dx.doi.org/10.1139/z04-110.

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The leatherback sea turtle, Dermochelys coriacea (Vandelli, 1761), has the most extensive range of any reptile, migrating from tropical and subtropical nesting areas to distant foraging habitats, including those in temperate and even boreal waters. This implies flexible thermal functioning. It has been inferred that leatherbacks support active foraging by keeping warm in cold water, rather than becoming lethargic as other marine turtles do. However, data consistent with this view have come from captive turtles in unnatural and stressful conditions. In the present case, foraging leatherbacks were captured at sea off Nova Scotia and their body temperature recorded within 10 min, before such large animals could change their body temperatures appreciably. Mean excess temperature over that of the sea surface (15.0–16.7 °C) averaged 8.2 °C. These results attest to, but underestimate, the capacity of free-swimming leatherbacks to keep warm in northern waters, as data from another turtle that was instrumented to record ocean temperature while diving revealed that leatherbacks foraging in this area at the same time of year may spend 40% of their time diving to waters cooler than the surface.

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Murphy, Colm. "Effects of deep diving on the trachea of the leatherback turtle." Boolean: Snapshots of Doctoral Research at University College Cork, no. 2010 (January 1, 2010): 119–24. http://dx.doi.org/10.33178/boolean.2010.27.

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This work is concerned with the effects of deep sea diving on the trachea (airway passage) of the leatherback turtle. Leatherback turtles are capable of diving to depths greater than 1,200 meters. Humans, in comparison, may only reach depths of around 30 meters unaided. It is believed that the response of the trachea along with its material properties plays a leading role in determining the depth that can be attained during a dive. The long term objective of this research is to investigate the response of the trachea of the leatherback turtle during deep dives (300-1250m). Questions remain as to the material properties from which the trachea is composed of and how exactly does the trachea respond as it undergoes a deep dive. Answering these questions will help not only to build a complete understanding of the leatherback’s ability to dive to depths greater than 1,000m, but will also inform ...

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Lutcavage, Molly E., Peter G. Bushnell, and David R. Jones. "Oxygen stores and aerobic metabolism in the leatherback sea turtle." Canadian Journal of Zoology 70, no. 2 (February 1, 1992): 348–51. http://dx.doi.org/10.1139/z92-051.

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The leatherback sea turtle, Dermochelys coriacea, is a large, deep-diving species that has a blood oxygen carrying capacity twice that of smaller, shallow-diving sea turtles. In this study we measured lung volume (by argon dilution) and blood volume (by dilution of Evans' blue dye) in leatherbacks to estimate partitioning of oxygen stores and their potential contribution to aerobic metabolism during diving. Blood volume (77 mL∙kg−1) was slightly higher, yet lung volume was considerably smaller (64 mL∙kg−1), than in other sea turtles, so that potential oxygen stores were almost equally divided between the lung (12 mL∙kg−1) and the blood and tissues (15 mL∙kg−1). At a body temperature of 32–34 °C and high heart rates (43–48/min), oxygen consumption of beached and netted leatherbacks was 1.1 mL∙min−1∙kg−1. The respiratory quotient exceeded unity, suggesting that the turtles were repaying an oxygen debt incurred in the netting procedure. Estimates of the probable utilization of oxygen stores and possible maximum and minimum oxygen uptakes were used to obtain a range of dive times (5–70 min) that can be supported aerobically.

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Werneck, M. R., and R. J. Da Silva. "Checklist of sea turtles endohelminth in Neotropical region." Helminthologia 53, no. 3 (September 1, 2016): 211–23. http://dx.doi.org/10.1515/helmin-2016-0045.

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SummaryThis paper presents a list of parasites described in sea turtles from the Neotropical region. Through the review of literature the occurrence of 79 taxa of helminthes parasites were observed, mostly consisting of the Phylum Platyhelminthes with 76 species distributed in 14 families and 2 families of the Phylum Nematoda within 3 species. Regarding the parasite records, the most studied host was the green turtle (Chelonia mydas) followed by the hawksbill turtle (Eretmochelys imbricata), olive ridley turtle (Lepidochelys olivacea), loggerhead turtle (Caretta caretta) and leatherback turtle (Dermochelys coriacea). Overall helminths were reported in 12 countries and in the Caribbean Sea region. This checklist is the largest compilation of data on helminths found in sea turtles in the Neotropical region.

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Rakotonirina, Berthin, and Andrew Cooke. "Sea turtles of Madagascar – their status, exploitation and conservation." Oryx 28, no. 1 (January 1994): 51–61. http://dx.doi.org/10.1017/s0030605300028295.

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Five species of sea turtles are known from Madagascar's coastal waters. Fishermen on the western and south-western coasts take green turtle Chelonia mydas, loggerhead turtle Caretta caretta and olive ridley Lepidochelys olivacea for their meat. The hawksbill turtle Eretmochelys imbricata is taken mainly for its shell and for making stuffed specimens while the leatherback Dermochelys coriacea is seldom caught. Anecdotal evidence of fishermen and dealers in turtle products, measurement of captured animals and personal observations of the authors all point to declines in numbers and average size for green and hawksbill turtles, coupled with marked declines in nesting rates for these and the olive ridley.

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Gardner, Beth, Patrick J. Sullivan, Stephen J. Morreale, and Sheryan P. Epperly. "Spatial and temporal statistical analysis of bycatch data: patterns of sea turtle bycatch in the North Atlantic." Canadian Journal of Fisheries and Aquatic Sciences 65, no. 11 (November 2008): 2461–70. http://dx.doi.org/10.1139/f08-152.

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Loggerhead ( Caretta caretta ) and leatherback ( Dermochelys coriacea ) sea turtle distributions and movements in offshore waters of the western North Atlantic are not well understood despite continued efforts to monitor, survey, and observe them. Loggerhead and leatherback sea turtles are listed as endangered by the World Conservation Union, and thus anthropogenic mortality of these species, including fishing, is of elevated interest. This study quantifies spatial and temporal patterns of sea turtle bycatch distributions to identify potential processes influencing their locations. A Ripley’s K function analysis was employed on the NOAA Fisheries Atlantic Pelagic Longline Observer Program data to determine spatial, temporal, and spatio-temporal patterns of sea turtle bycatch distributions within the pattern of the pelagic fishery distribution. Results indicate that loggerhead and leatherback sea turtle catch distributions change seasonally, with patterns of spatial clustering appearing from July through October. The results from the space–time analysis indicate that sea turtle catch distributions are related on a relatively fine scale (30–200 km and 1–5 days). The use of spatial and temporal point pattern analysis, particularly K function analysis, is a novel way to examine bycatch data and can be used to inform fishing practices such that fishing could still occur while minimizing sea turtle bycatch.

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Lockley, Martin G., Hayley C. Cawthra, Jan C. De Vynck, Charles W. Helm, Richard T. McCrea, and Ronel Nel. "New fossil sea turtle trackway morphotypes from the Pleistocene of South Africa highlight role of ichnology in turtle paleobiology." Quaternary Research 92, no. 3 (August 23, 2019): 626–40. http://dx.doi.org/10.1017/qua.2019.40.

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AbstractMore than 130 late Pleistocene trackway sites from the coastal eolianites and beach deposits of the Cape south coast, South Africa, have previously mostly yielded tracks of large mammals and birds. However, two sites east of Still Bay, and a third near Garden Route National Park, yield distinctive trackways of hatchling sea turtles, made during the short posthatching (postemergence) interval when the trackmakers headed for the sea. One assemblage of approximately parallel trackways indicates smaller loggerhead turtle hatchlings, with alternating gaits, and contrasts with a wider trackway indicating a leatherback turtle hatchling. These are the world's first reports of fossil traces that document this brief “run-for the-sea” phenomenon. They help delineate late Pleistocene sea turtle breeding ranges and indicate climatic conditions along the Cape south coast. Ichnotaxonomically defined swim tracks of large adult sea turtles are known from a few Mesozoic sites. Likewise, walking and swim traces of terrestrial freshwater turtles are also known from the Mesozoic and Cenozoic. However, as no ichnotaxonomy exists for these diagnostic hatchling trails, we assign the trackways of the inferred loggerheads to the new ichnotaxon Australochelichnus agulhasii ichnogen. et ichnosp. nov., and the inferred leatherback trackway to Marinerichnus latus ichnogen. et ichnosp. nov.

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Lehman, Thomas M., and Susan L. Tomlinson. "Terlinguachelys fischbecki, a new genus and species of sea turtle (Chelonioidea: Protostegidae) from the Upper Cretaceous of Texas." Journal of Paleontology 78, no. 6 (November 2004): 1163–78. http://dx.doi.org/10.1017/s0022336000043973.

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Remains of a large sea turtle, Terlinguachelys fischbecki n. gen. and sp., were recovered from paralic deposits of the Upper Cretaceous (Campanian) Aguja Formation in Big Bend National Park, Texas. T. fischbecki is a primitive protostegid that retains a constricted humerus, well ossified plastron and costals, prominent retroarticular process on the lower jaw, and long slender femora; however, it has some features, such as a prominent tubercle at the base of the scapular acromion process, found elsewhere only in derived leatherback sea turtles. The unique combination of primitive and derived traits in T. fischbecki illustrates further diversity among Cretaceous sea turtles and another case of parallelism common in sea turtle phylogeny.

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Eckert, Scott A. "Swim speed and movement patterns of gravid leatherback sea turtles(Dermochelys coriacea) at St Croix, US Virgin Islands." Journal of Experimental Biology 205, no. 23 (December 1, 2002): 3689–97. http://dx.doi.org/10.1242/jeb.205.23.3689.

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SUMMARYSwim speed, dive behavior and movements were recorded for seven female leatherback sea turtles (Dermochelys coriacea Vandelli 1761) during a single internesting interval near St Croix in the US Virgin Islands. Modal speeds ranged from 0.56 to 0.84 m s-1, maximum speed range 1.9-2.8 m s-1. Turtles swam continuously throughout the day and night. There were two swim-speed patterns; the most common was slightly U-shaped,with high speeds at the initiation and conclusion of the dive, and the less common was continuous high-speed swimming. The U-shaped speed patterns were coincident with vertical diving by the turtles, while the second pattern occurred most frequently during the daytime, with the turtle swimming within 2 m of the surface. This latter swim behavior appeared to be designed to maximize efficiency for long-distance travel. The hypothesis that leatherbacks rest or bask at midday during their internesting interval is refuted by this study.

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Watson, John W., Sheryan P. Epperly, Arvind K. Shah, and Daniel G. Foster. "Fishing methods to reduce sea turtle mortality associated with pelagic longlines." Canadian Journal of Fisheries and Aquatic Sciences 62, no. 5 (May 1, 2005): 965–81. http://dx.doi.org/10.1139/f05-004.

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Changes in hook design and bait type were investigated as measures to reduce the bycatch of sea turtles on pelagic longlines in the western North Atlantic Ocean. Specifically, the effectiveness of 18/0 circle hooks and mackerel (Scomber scombrus) bait was evaluated with respect to reducing sea turtle interactions and maintaining swordfish (Xiphias gladius) and tuna (Thunnus spp.) catch rates. Individually, circle hooks and mackerel bait significantly reduced both loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) sea turtle bycatch. Circle hooks also significantly reduced the rate of hook ingestion by the loggerheads, potentially reducing postrelease mortality. The combination of circle hooks and mackerel bait was even more effective for loggerhead turtles and had no negative effect on swordfish catch. These modifications in fishing methods, in conjunction with tools developed to remove hooks and line from the turtles, significantly reduced the capture rate of sea turtles and potentially the post-hooking mortality of those that were caught and did not negatively impact the primary target species catch rate. In addition, these mitigation measures have the potential to reduce mortality of sea turtles and other bycatch species worldwide.

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James, Michael C., Ransom A. Myers, and C. Andrea Ottensmeyer. "Behaviour of leatherback sea turtles, Dermochelys coriacea , during the migratory cycle." Proceedings of the Royal Society B: Biological Sciences 272, no. 1572 (July 11, 2005): 1547–55. http://dx.doi.org/10.1098/rspb.2005.3110.

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Leatherback sea turtles, Dermochelys coriacea , undertake broad oceanic movements. While satellite telemetry has been used to investigate the post-nesting behaviour of female turtles tagged on tropical nesting beaches, long-term behavioural patterns of turtles of different sexes and sizes have not been described. Here we investigate behaviour for 25 subadult and adult male and female turtles satellite-tagged in temperate waters off Nova Scotia, Canada. Although sex and reproductive condition contributed to variation in migratory patterns, the migratory cycle of all turtles included movement between temperate and tropical waters. Marked changes in rates of travel, and diving and surfacing behaviour, accompanied southward movement away from northern foraging areas. As turtles approached higher latitudes the following spring and summer, they assumed behaviours consistent with regular foraging activity and eventually settled in coastal areas off Canada and the northeastern USA. Behavioural patterns corresponding to various phases of the migratory cycle were consistent across multiple animals and were repeated within individuals that completed return movements to northern waters. We consider the potential biological significance of these patterns, including how turtle behaviour relates to predator avoidance, thermoregulation and prey distribution.

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Barata, Paulo C. R., Eduardo H. S. M. Lima, Márcio Borges-Martins, Juarez T. Scalfoni, Claudio Bellini, and Salvatore Siciliano. "Records of the leatherback sea turtle (Dermochelys coriacea) on the Brazilian coast, 1969–2001." Journal of the Marine Biological Association of the United Kingdom 84, no. 6 (November 23, 2004): 1233–40. http://dx.doi.org/10.1017/s0025315404010720h.

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Data from several sources and original data are presented regarding sightings, strandings and incidental captures of leatherback sea turtles (Dermochelys coriacea) on the Brazilian coast in a 33 year period, from 1969 to 2001. Two of the turtles were small juveniles (curved carapace length=40 cm and approximately 85 cm) and the remaining animals with known carapace size were large juveniles or adults. The origin of leatherbacks observed in Brazil is unknown. Several colonies in South America, including a Brazilian one, in the Caribbean, in western Africa and even in eastern South Africa could be the source of these turtles. The data presented here suggest that more effort should be directed to the assessment of the impact of fishing gear and marine pollution on leatherbacks and that systematic surveys on beaches should be maintained in order to monitor long term fluctuations in stranding levels and spatial stranding patterns. Genetic studies and satellite telemetry would be helpful in clarifying the origin of leatherbacks stranded or incidentally captured on the Brazilian coast.

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Caut, Stéphane, Elodie Guirlet, Pascal Jouquet, and Marc Girondot. "Influence of nest location and yolkless eggs on the hatching success of leatherback turtle clutches in French Guiana." Canadian Journal of Zoology 84, no. 6 (June 2006): 908–15. http://dx.doi.org/10.1139/z06-063.

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The hatching success of leatherback turtles, Dermochelys coriacea (Vandelli, 1761), is influenced by heterogeneously distributed ecological factors. However, the hatching success according to nest-site selection has rarely been studied and little is known about the role of nest-site selection and infertile (yolkless) egg production on the predation rate and development of fertile eggs in leatherback turtle nests laid in French Guiana. A field study of 99 leatherback turtle nests was conducted to quantify the relationships between hatching success and (i) the nest-site selection (i.e., vegetation line, sea tide line) and (ii) the infertile eggs, especially their state after incubation (i.e., hydrated or dehydrated) and their effects on predation rate. We found that hatching success on this beach was very low (38.2%). This study illustrates that nest-site selection influences the predation rate and the dehydration of yolkless eggs, while the production of yolkless eggs by leatherback turtles has consequences on nest success. The proportion of yolkless eggs in the clutch, as well as their status at the end of incubation (hydrated or not, preyed upon), correlates with predation rate, development of yolked eggs, and hatching success. There was a significant relationship between nest location (relative to high tide line and vegetation line) and both the predation rates of eggs and the percentage of dehydrated yolkless eggs within a clutch. The production of yolkless eggs was related to hatching success and supports the hypothesis that yolkless eggs have a positive effect on the future of the clutch.

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Eckert, Scott A., Karen L. Eckert, P. Ponganis, and G. L. Kooyman. "Diving and foraging behavior of leatherback sea turtles (Dermochelys coriacea)." Canadian Journal of Zoology 67, no. 11 (November 1, 1989): 2834–40. http://dx.doi.org/10.1139/z89-399.

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Remote time–depth recorders (TDR) were deployed on six gravid leatherbacks nesting on Sandy Point, St. Croix. Dive behavior was monitored continuously for each turtle during internesting intervals ranging from 9 to 11 days. Dive duration averaged 9.9 min/dive (SD = 5.3, n = 5096); mean depth was 61.6 m (SD = 59.1, n = 5096). One turtle dived twice beyond the range of her TDR to depths we estimate >1000 m. Postdive surfacing intervals averaged 4.9 min/dive (SD = 13.1, n = 5090). Differences in mean dive depth, dive duration, and surface intervals among turtles were not attributable to differences in body size (length or mass). Distinct diel periodicity was observed in dive behavior; submergence intervals were longest at dawn, declined throughout the day, and were shortest at dusk. Night dives (19:00–04:59) were shorter, shallower, and more frequent than day dives (05:00–18:59). Dive depth was less variable at night than during the day. The dive pattern suggests nocturnal foraging within the deep scattering layer, a hypothesis that is corroborated by seasonal weight loss data.

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Davenport, J., D. L. Holland, and J. East. "Thermal and biochemical characteristics of the lipids of the leatherback turtle Dermochelys coriacea: evidence of endothermy." Journal of the Marine Biological Association of the United Kingdom 70, no. 1 (February 1990): 33–41. http://dx.doi.org/10.1017/s0025315400034172.

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Unlike other sea turtles, the leatherback Dermochelys coriacea forages widely in temperate waters during summer and dives to abyssal depths (>1000 m) where temperatures are low. There is strong anatomical plus limited physiological evidence in favour of at least facultative endothermy. The lipids of leatherbacks exhibit features which are consistent with maintenance of a core temperature above ambient levels when in cool waters. The lipid of flipper adipose tissue freezes at a lower temperature than lipids extracted from the blubber lining carapace and plastron. Lipid freezing points in leatherbacks are lower than for tropical caimans or terrestrial sheep, but higher than for lipids taken from the blubber of a grey seal. Leatherback adipose tissues show levels of unsaturation in neutral lipid fractions intermediate between those of seals and sheep.

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Holtz, Bethany, Kelly R. Stewart, and Wendy E. D. Piniak. "Influence of environmental and anthropogenic acoustic cues in sea-finding of hatchling leatherback (Dermochelys coriacea) sea turtles." PLOS ONE 16, no. 7 (July 1, 2021): e0253770. http://dx.doi.org/10.1371/journal.pone.0253770.

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Although the visual and geomagnetic orientation cues used by sea turtle hatchlings during sea-finding have been well studied, the potential for auditory stimuli to act as an orientation cue has not been explored. We investigated the response of sea turtle hatchlings to natural and anthropogenic noises present on their nesting beaches during sea-finding. The responses of hatchling leatherback sea turtles, Dermochelys coriacea, collected from the Sandy Point National Wildlife Refuge, St. Croix, were measured in the presence of aerial acoustic sounds within hatchlings’ hearing range of 50 to 1600 Hz. The highest sound energy produced by beach waves occurs at frequencies 50–1000 Hz, which overlaps with the most sensitive hearing range of hatchling leatherbacks (50–400 Hz). Natural beach wave sounds, which have highest sound energy at frequencies of 50–1000 Hz, may be masked by human conversations (85–650 Hz) and vehicle traffic noise (60–8000 Hz). In the presence of three stimuli, a) beach wave sounds (72.0 dB re: 20 μPa), b) human conversation (72.4 dB re: 20 μPa), and c) vehicle traffic noise (71.1 dB re: 20 μPa), hatchlings exhibited no phonotaxic response (wave sounds: mean angle = 152.1°, p = 0.645; human conversation: mean angle = 67.4°, p = 0.554; traffic noise: mean angle = 125.7°, p = 0.887). These results may be due to the hatchlings being unable to localize sounds in the experimental arena. Visual and auditory cues may also converge to affect sea-finding orientation. Future studies should focus on the localization ability of sea turtles and on the role that sound may play in orientation when combined with other sensory and environmental cues.

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Yewen, Martha Yulita, and I. Made Bayu Ariwangsa. "Peran Stakeholders dalam Konservasi Penyu Belimbing di Pantai Peneluran Jamursba Medi Kabupaten Tambrauw Provinsi Papua Barat." JURNAL DESTINASI PARIWISATA 5, no. 2 (November 1, 2018): 349. http://dx.doi.org/10.24843/jdepar.2017.v05.i02.p27.

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The conservation potential of Leatherback Sea Turtle in Jamursba Medi Spawning Beach is for ecotourism attraction. This research was conducted at PeneluranJamursbaMedi Beach. This research was conducted to find out the potential of Leatherback Sea Turtle at JamursbaMediSpawningBeach as ecotourism attraction in Tambrauw Regency and also to find out the form of cooperation of Stakeholders in the area of Jamursba Medi Spawning Beach, Regency of Tambrauw, Province of West Papua. The type of data being used in this research was qualitative and quantitative with primary and secondary data source obtained through data sampling technique of depth interview observation, literature study with informant determination technique of purposive sampling and data analysis technique of descriptive qualitative. The result of research shows that in the area of Spawning Beach, Leatherback Sea Turtles have a potential to support tourism development in the form of natural, cultural and human. These three potencies are the assets to give contribution for tourism development and management of coastal park and has potential for ecotourism sector. So participation and active role of stakeholders namely Government, Population, and non-governmental organizations / WWF (World Wildlife Fund) is required for advancement and development in the area of Jamursba Medi Spawning Beach. Key words: Potency, Ecotourism Conservation, Stakeholder.

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Holst, Meike. "Marine Mammal and Sea Turtle Sightings During a Survey of the Endeavour Segment of the Juan de Fuca Ridge, British Columbia." Canadian Field-Naturalist 131, no. 2 (October 29, 2017): 120–24. http://dx.doi.org/10.22621/cfn.v131i2.1873.

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Marine mammals and sea turtles were documented as part of a monitoring and mitigation program during a seismic study offshore (~250 km) from Vancouver island, British Columbia, during August–September 2009. Forty-one marine mammals in nine groups were sighted. Dall’s Porpoise (Phocoenoides dalli) was the most frequently sighted species. A Sperm Whale (Physeter macrocephalus), a pod of Pacific White-sided Dolphins (Lagenorhynchus obliquidens), an unidentified toothed whale, a Northern Elephant Seal (Mirounga angustirostris), and a leatherback Turtle (Dermochelys coriacea) were also observed. These data augment current knowledge on the occurrence of marine mammals and sea turtles in the offshore waters of British Columbia.

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Darquea, Jodie J., Clara Ortiz-Alvarez, Francisco Córdova-Zavaleta, Robert Medina, Alessandra Bielli, Joanna Alfaro-Shigueto, and Jeffrey C. Mangel. "Trialing net illumination as a bycatch mitigation measure for sea turtles in a small-scale gillnet fishery in Ecuador." Latin American Journal of Aquatic Research 48, no. 3 (July 6, 2020): 446–55. http://dx.doi.org/10.3856/vol48-issue3-fulltext-2428.

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In Ecuador, one of the main hazards for threatened marine species, such as sea turtles, is small-scale fisheries bycatch. At a global scale, currently, bycatch reduction technologies (BRTs) are being tested in many coastal nations to mitigate this issue. Despite some advances in Ecuadorian efforts for wildlife protection, BRTs to reduce bycatch have yet to be assessed. The purpose of this study was to test the BRT of net illumination using violet light-emitting diodes (LEDs) as a mitigation measure to reduce sea turtle interactions in the small-scale driftnet fishery operating from the ports of Santa Rosa, Puerto Lopez and Jaramijo. A total of 146 pairs of experimental sets (control and illuminated panes) were deployed in all ports. A generalized linear mixed-effect model (GLMM) was employed to analyze the bycatch per unit of effort (BPUE) for sea turtles, and the catch per unit of effort (CPUE) for target species; for both control and illuminated panes. Thirty-two sea turtles from three species were observed captured: olive ridley Lepidochelys olivacea (n=18), green Chelonia mydas (n=13) and leatherback turtles Dermochelys coriacea (n=1). Turtle species-specific modeling showed bycatch of green turtles declined by 93% in illuminated nets compared with control, non-illuminated nets, whereas no significant difference between control and illuminated nets was observed for olive ridley turtles. The catch per unit effort of the target pelagic fish species including skipjack tuna, yellowfin tuna, mahi-mahi, thresher shark and smooth hammerhead shark was not affected by net illumination. Our results represent the first evaluation of the effects of net illumination using LEDs on reducing marine turtle bycatch in Ecuadorian small-scale driftnet fisheries. Despite its relatively small sample size, these results could be used by fisheries managers to support the implementation or further testing of this BRT in gillnet fisheries along the Ecuadorian coast.

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Witt, Matthew J., Eric Augowet Bonguno, Annette C. Broderick, Michael S. Coyne, Angela Formia, Alain Gibudi, Gil Avery Mounguengui Mounguengui, et al. "Tracking leatherback turtles from the world's largest rookery: assessing threats across the South Atlantic." Proceedings of the Royal Society B: Biological Sciences 278, no. 1716 (January 5, 2011): 2338–47. http://dx.doi.org/10.1098/rspb.2010.2467.

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Despite extensive work carried out on leatherback turtles ( Dermochelys coriacea ) in the North Atlantic and Indo-Pacific, very little is known of the at-sea distribution of this species in the South Atlantic, where the world's largest population nests in Gabon (central Africa). This paucity of data is of marked concern given the pace of industrialization in fisheries with demonstrable marine turtle bycatch in African/Latin American waters. We tracked the movements of 25 adult female leatherback turtles obtaining a range of fundamental and applied insights, including indications for methodological advancement. Individuals could be assigned to one of three dispersal strategies, moving to (i) habitats of the equatorial Atlantic, (ii) temperate habitats off South America or (iii) temperate habitats off southern Africa. While occupying regions with high surface chlorophyll concentrations, these strategies exposed turtles to some of the world's highest levels of longline fishing effort, in addition to areas with coastal gillnet fisheries. Satellite tracking highlighted that at least 11 nations should be involved in the conservation of this species in addition to those with distant fishing fleets. The majority of tracking days were, however, spent in the high seas, where effective implementation of conservation efforts is complex to achieve.

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James, Amanda, Annie Page-Karjian, Kate E. Charles, Jonnel Edwards, Christopher R. Gregory, Sonia Cheetham, Brian P. Buter, and David P. Marancik. "Chelonid Alphaherpesvirus 5 Prevalence and First Confirmed Case of Sea Turtle Fibropapillomatosis in Grenada, West Indies." Animals 11, no. 6 (May 21, 2021): 1490. http://dx.doi.org/10.3390/ani11061490.

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Chelonid alphaherpesvirus 5 (ChHV5) is strongly associated with fibropapillomatosis, a neoplastic disease of sea turtles that can result in debilitation and mortality. The objectives of this study were to examine green (Chelonia mydas), hawksbill (Eretmochelys imbricata), and leatherback (Dermochelys coriacea) sea turtles in Grenada, West Indies, for fibropapillomatosis and to utilize ChHV5-specific PCR, degenerate herpesvirus PCR, and serology to non-invasively evaluate the prevalence of ChHV5 infection and exposure. One-hundred and sixty-seven turtles examined from 2017 to 2019 demonstrated no external fibropapilloma-like lesions and no amplification of ChHV5 DNA from whole blood or skin biopsies. An ELISA performed on serum detected ChHV5-specific IgY in 18/52 (34.6%) of green turtles tested. In 2020, an adult, female green turtle presented for necropsy from the inshore waters of Grenada with severe emaciation and cutaneous fibropapillomas. Multiple tumors tested positive for ChHV5 by qPCR, providing the first confirmed case of ChHV5-associated fibropapillomatosis in Grenada. These results indicate that active ChHV5 infection is rare, although viral exposure in green sea turtles is relatively high. The impact of fibropapillomatosis in Grenada is suggested to be low at the present time and further studies comparing host genetics and immunologic factors, as well as examination into extrinsic factors that may influence disease, are warranted.

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Whiting, AU, M. Chaloupka, N. Pilcher, P. Basintal, and CJ Limpus. "Sampling nesting sea turtles: optimizing survey design to minimize error." Marine Ecology Progress Series 674 (September 16, 2021): 257–70. http://dx.doi.org/10.3354/meps13824.

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Many sea turtle studies globally use counts of nesting activities as a proxy for population abundance estimates and as an indicator of trends within the population. Often these populations are sampled temporally and spatially, but few previous studies have examined the impact of different sampling techniques on the accuracy of these estimates. We investigated temporal sampling errors using a multi-species approach, examining 10 populations comprising green, loggerhead and leatherback sea turtles. Sampling errors were investigated from random, regular and continuous sampling regimes spanning 5-80% coverage. A count approach was used rather than an individual-based capture-mark-recapture approach to broaden the scope and application of the research. Modelling showed that even low survey coverage of 5% gave reasonably accurate estimates of annual nesting activity, with estimated errors of ca. 20% (mean + 1 SD equalling 84.1% of surveys). Survey error is low relative to changes in abundance from the inter-annual variations in nesting activity that occur in sea turtle populations. Thus, annual studies are important to estimate sea turtle abundance, even if these studies have low survey coverage. An increase in survey effort may be more cost effective if spent combining estimates of total nesting activity with sampling turtles as part of a capture-mark-recapture study. This approach will provide a second estimate of annual abundance as well as an estimate of demographic parameters including clutch frequencies, remigration intervals, survivorship, immigration and emigration. This estimation of sampling errors may be useful in the design of monitoring programmes and can be used to guide management and policy decisions.

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MAJEWSKA, ROKSANA. "Tursiocola neliana sp. nov (Bacillariophyceae) epizoic on South African leatherback sea turtles (Dermochelys coriacea) and new observations on the genus Tursiocola." Phytotaxa 453, no. 1 (July 20, 2020): 1–15. http://dx.doi.org/10.11646/phytotaxa.453.1.1.

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Tursiocola, a presumably exclusively epizoic diatom genus, comprises species found on various aquatic animals such as cetaceans, manatees, and marine and freshwater turtles. The genus is characterised by linear or lanceolate valves with well-developed pseudosepta at both poles, a valvocopula with three pairs of siliceous tabs, and a butterfly-like structure extending from the central nodule on the internal side of the valve. The current study describes a novel species of Tursiocola, T. neliana Majewska sp. nov. that grows epizoically on leatherback sea turtles from the Eastern Coast of South Africa based on detailed observations using light and scanning electron microscopy. The new taxon resembles the other currently known sea turtle-associated Tursiocola species in possessing relatively small, slightly heteropolar valves with acute apices and a strongly reduced butterfly structure on the internal side. However, T. neliana differs from all other members of the genus in being distinctly dorsiventral, with a clearly bowtie-shaped central area, unequal stria density on two sides of the raphe-sternum, and up to 8 areolae per stria. The description of the new taxon brings the total number of the sea turtle-associated Tursiocola species known so far up to four. An emended description of Tursiocola is proposed based on the new observations presented in this and other recent reports. Furthermore, the current understanding of the genus ecology is summarised.

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Eckert, Karen Lind. "Twinning in Leatherback Sea Turtle (Dermochelys coriacea) Embryos." Journal of Herpetology 24, no. 3 (September 1990): 317. http://dx.doi.org/10.2307/1564404.

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30

Fossette, Sabrina, Adrian C. Gleiss, James P. Casey, Andrew R. Lewis, and Graeme C. Hays. "Does prey size matter? Novel observations of feeding in the leatherback turtle ( Dermochelys coriacea ) allow a test of predator–prey size relationships." Biology Letters 8, no. 3 (November 16, 2011): 351–54. http://dx.doi.org/10.1098/rsbl.2011.0965.

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Optimal foraging models predict that large predators should concentrate on large prey in order to maximize their net gain of energy intake. Here, we show that the largest species of sea turtle, Dermochelys coriacea , does not strictly adhere to this general pattern. Field observations combined with a theoretical model suggest that a 300 kg leatherback turtle would meet its energetic requirements by feeding for 3–4 h a day on 4 g jellyfish, but only if prey were aggregated in high-density patches. Therefore, prey abundance rather than prey size may, in some cases, be the overriding parameter for foraging leatherbacks. This is a classic example where the presence of small prey in the diet of a large marine predator may reflect profitable foraging decisions if the relatively low energy intake per small individual prey is offset by high encounter rates and minimal capture and handling costs. This study provides, to our knowledge, the first quantitative estimates of intake rate for this species.

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31

Chevallier, D., M. Girondot, R. Berzins, J. Chevalier, B. de Thoisy, J. Fretey, L. Kelle, and JD Lebreton. "Survival and breeding interval of an endangered marine vertebrate, the leatherback turtle Dermochelys coriacea, in French Guiana." Endangered Species Research 41 (February 13, 2020): 153–65. http://dx.doi.org/10.3354/esr01013.

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In the context of global change, endangered species such as sea turtles undergo strong population dynamics changes. Understanding demographic processes inducing such changes is critical for developing appropriate measures for conservation and management. Nesting females of the French Guiana population of leatherback sea turtles Dermochelys coriacea represented 40% of the world’s total in 2001; today, they represent only 10%. Here, we analyze data from the long-term monitoring program of leatherbacks in French Guiana, based on 28 yr of capture-mark-recapture data from 46051 individuals in northwestern French Guiana. We used multievent models (multistate capture-recapture models with state uncertainty) to represent the main peculiarity of the life cycle, intermittent reproduction, and to take advantage of the use of several different types of marks to account for mark loss and incomplete detection. The average annual adult survival probability (mean ± SE) 0.789 ± 0.009 is low compared to published estimates for this species. By combining the estimates of departure and return probabilities, we provide an estimate of the interval among laying seasons equal to 2.777 ± 0.118 yr, which matches previous findings. Taking survival into account, this interval translates into an average of 1.704 ± 0.034 further reproductive seasons for an adult female having just bred, which is remarkably low compared to other long-lived vertebrates. The representation of the life cycle and mark loss in our models provides a sound structure for broader and richer analyses to extract biological information from marked individuals and offers an invaluable source of demographic information on leatherbacks, a species for which only a small segment of the population is accessible to intermittent sampling.

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32

Eckert, SA. "Distribution of juvenile leatherback sea turtle Dermochelys coriacea sightings." Marine Ecology Progress Series 230 (2002): 289–93. http://dx.doi.org/10.3354/meps230289.

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33

Brudenall, Denise K., Ivan R. Schwab, and Kerstin A. Fritsches. "Ocular morphology of the Leatherback sea turtle (Dermochelys coriacea)." Veterinary Ophthalmology 11, no. 2 (March 2008): 99–110. http://dx.doi.org/10.1111/j.1463-5224.2008.00607.x.

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34

Lutcavage, Molly E., Peter G. Bushnell, and David R. Jones. "Oxygen Transport in the Leatherback Sea Turtle Dermochelys coriacea." Physiological Zoology 63, no. 5 (September 1990): 1012–24. http://dx.doi.org/10.1086/physzool.63.5.30152626.

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35

Godley, B. J., M. J. Gaywood, R. J. Law, C. J. McCarthy, C. McKenzie, I. A. P. Patterson, R. S. Penrose, R. J. Reid, and H. M. Ross. "Patterns of Marine Turtle Mortality in British Waters (1992–1996) with Reference to Tissue Contaminant Levels." Journal of the Marine Biological Association of the United Kingdom 78, no. 3 (August 1998): 973–84. http://dx.doi.org/10.1017/s002531540004491x.

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Mortality patterns of marine turtles entangled in fishing gear, found dead at sea or stranded dead on and around the coast of Britain in the period 1992–1996 are described. Of a total of 38 dead turtles identified, 35 were leatherback turtles (Dermochelys coriacea) and three were loggerhead turtles (Caretta caretta). All D. coriacea were considered adults or subadults nearing sexual maturity. Six individuals were assessed as females, ten were classified as males and 19 were not sexed. Dermochelys coriacea (N=20 measured) ranged from 120 to 210 cm in curved carapace length (mean, 152 cm). The three C. caretta were juveniles, and ranged from 15 to 30 cm curved carapace length. Possible origins, causes of mortality and interactions with fisheries are discussed. In addition, contaminant levels were determined in the tissues of three D. coriacea. Concentrations of organic contaminants determined were found to be low.

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36

Escobar-Lasso, Sergio, Luis Fonseca, Wilbert N. Villachica, Hansel Herrera, Roldán A. Valverde, Wagner Quirós-Pereira, Marta Pesquero, and Pamela T. Plotkin. "First field observation of the predation by Jaguar (Panthera onca) on Olive Ridley sea turtle (Lepidochelys olivacea) at Nancite Beach, Santa Rosa National Park, Costa Rica." Mammalogy Notes 3, no. 1 (January 15, 2016): 20–23. http://dx.doi.org/10.47603/manovol3n1.20-23.

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Jaguars have been recorded preying on adult female sea turtles on their nesting beaches in Costa Rica, Guyana, Mexico and Suriname (Fretey 1977, Autar 1994, Cuevas et al. 2014, Guildera et al. 2015). Jaguars prey on Green (Chelonia mydas), Olive Ridley (Lepidochelys olivacea), Hawksbill (Eretmochelys imbricata), and Leatherback (Dermochelys coriacea) sea turtles (see Fretey 1977, Autar 1994, Carrillo et al. 1994, Chinchilla 1997, Tröeng 2000, Heithaus et al. 2008, Veríssimo et al. 2012, Arroyo-Arce et al. 2014, Cuevas et al. 2014, Arroyo-Arce & Salom-Pérez 2015, Guildera et al. 2015). The capture effort and risk of injury associated with the predation of nesting sea turtles is expected to be lower relative to other prey species in the jaguar’s diet (Cavalcanti & Gese 2010). Additionally, they can be key resources when other pr ey availability is low (Veríssimo et al. 2012).

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37

Hudson, David M., and Peter L. Lutz. "Salt Gland Function in the Leatherback Sea Turtle, Dermochelys coriacea." Copeia 1986, no. 1 (February 10, 1986): 247. http://dx.doi.org/10.2307/1444922.

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38

Lohmann, K. J., and CMF Lohmann. "A Light-Independent Magnetic Compass in the Leatherback Sea Turtle." Biological Bulletin 185, no. 1 (August 1993): 149–51. http://dx.doi.org/10.2307/1542138.

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39

Smith, Hobart M., and Anders G. J. Rhodin. "Authorship of the Scientific Name of the Leatherback Sea Turtle." Journal of Herpetology 20, no. 3 (September 1986): 450. http://dx.doi.org/10.2307/1564512.

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40

Chen, Irene H., Wen Yang, and Marc A. Meyers. "Leatherback sea turtle shell: A tough and flexible biological design." Acta Biomaterialia 28 (December 2015): 2–12. http://dx.doi.org/10.1016/j.actbio.2015.09.023.

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41

Kot, Connie Y., Andre M. Boustany, and Patrick N. Halpin. "Temporal patterns of target catch and sea turtle bycatch in the US Atlantic pelagic longline fishing fleet." Canadian Journal of Fisheries and Aquatic Sciences 67, no. 1 (January 2010): 42–57. http://dx.doi.org/10.1139/f09-160.

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Sea turtle bycatch in pelagic longline fishing gear is an ongoing threat to the conservation of sea turtle populations. However, these bycatch events do not occur uniformly in space or time. Leatherback ( Dermochelys coriacea ) and loggerhead ( Caretta caretta ) bycatch rates reported in large fishing regions exhibited different degrees of interannual variability. Target catch and sea turtle bycatch in most regions displayed strong periodicity that corresponded to seasons (~365 days) and/or moon phase (~29 days). When trends in catch and bycatch rates were examined by month and moon phase, the significant periods of higher and lower catch and bycatch related to swordfish ( Xiphias gladius ), yellowfin tuna ( Thunnus albacares ), and sea turtle temporal distributions in foraging and spawning/nesting, oceanographic and prey conditions, and foraging behavior. Catch and bycatch rates tended to depend more on a seasonal rather than a lunar time scale, although there is likely an interaction between the two. These findings provide insights to the susceptibility of target catch and bycatch, regional and temporal patterns of fishing effort, and potential guidance for resource management and conservation.

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42

Bandimere, A., FV Paladino, JR Spotila, A. Panagopoulou, J. Diéguez-Uribeondo, and P. Santidrián Tomillo. "Effects of egg mass and local climate on morphology of East Pacific leatherback turtle Dermochelys coriacea hatchlings in Costa Rica." Marine Ecology Progress Series 669 (July 8, 2021): 191–200. http://dx.doi.org/10.3354/meps13747.

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Global climate patterns are shifting due to anthropogenic causes, putting pressure on many species that are unable to adapt to such rapid changes. Sea turtle clutches, for example, normally develop between 26 and 33°C, but tolerate higher temperatures at the end of development. High temperatures, protracted rainfall, and droughts have been linked to fewer hatchlings. Likewise, climatic conditions can affect the size of sea turtle hatchlings, which could affect their probability of survival. We analyzed the effects of a biotic factor (egg mass) and environmental factors (precipitation and incubation temperature) on East Pacific leatherback turtle Dermochelys coriacea hatchling sizes in Costa Rica. Hatchling size (mass, straight carapace length, straight carapace width, and head width) was affected by both biotic and environmental factors. While egg mass was the strongest predictor for hatchling mass, temperature was the strongest for carapace length and head width. Carapace width was most strongly predicted by precipitation. Hatchling carapace length and width decreased with increases in temperature and increased with higher levels of precipitation. Hatchling mass also decreased with increasing temperature, although the relationship was not statistically significant. Head width decreased with greater precipitation during development. These findings suggest that increases in temperature and decreases in precipitation may not only decrease the number of hatchlings produced, but may also produce smaller leatherback hatchlings in Pacific Costa Rica, which may impair hatchling survival in the first hours after emergence.

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43

Nordstrom, B., MC James, K. Martin, and B. Worm. "Tracking jellyfish and leatherback sea turtle seasonality through citizen science observers." Marine Ecology Progress Series 620 (June 18, 2019): 15–32. http://dx.doi.org/10.3354/meps12978.

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44

Donnelly, Kyle, Thomas B. Waltzek, James F. X. Wellehan, Nicole I. Stacy, Maria Chadam, and Brian A. Stacy. "Mycobacterium haemophilum infection in a juvenile leatherback sea turtle (Dermochelys coriacea)." Journal of Veterinary Diagnostic Investigation 28, no. 6 (October 3, 2016): 718–21. http://dx.doi.org/10.1177/1040638716661746.

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45

Patino-Martinez, Juan, Adolfo Marco, Liliana Quiñones, and Lucy A. Hawkes. "The potential future influence of sea level rise on leatherback turtle nests." Journal of Experimental Marine Biology and Ecology 461 (December 2014): 116–23. http://dx.doi.org/10.1016/j.jembe.2014.07.021.

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46

Dodge, Kara L., Benjamin Galuardi, and Molly E. Lutcavage. "Orientation behaviour of leatherback sea turtles within the North Atlantic subtropical gyre." Proceedings of the Royal Society B: Biological Sciences 282, no. 1804 (April 7, 2015): 20143129. http://dx.doi.org/10.1098/rspb.2014.3129.

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Leatherback sea turtles ( Dermochelys coriacea ) travel thousands of kilometres between temperate feeding and tropical breeding/over-wintering grounds, with adult turtles able to pinpoint specific nesting beaches after multi-year absences. Their extensive migrations often occur in oceanic habitat where limited known sensory information is available to aid in orientation. Here, we examined the migratory orientation of adult male, adult female and subadult leatherbacks during their open-ocean movements within the North Atlantic subtropical gyre by analysing satellite-derived tracks from fifteen individuals over a 2-year period. To determine the turtles' true headings, we corrected the reconstructed tracks for current drift and found negligible differences between current-corrected and observed tracks within the gyre. Individual leatherback headings were remarkably consistent throughout the subtropical gyre, with turtles significantly oriented to the south-southeast. Adult leatherbacks of both sexes maintained similar mean headings and showed greater orientation precision overall. The consistent headings maintained by adult and subadult leatherbacks within the gyre suggest use of a common compass sense.

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Lutcavage, Molly, and Peter L. Lutz. "Metabolic Rate and Food Energy Requirements of the Leatherback Sea Turtle, Dermochelys coriacea." Copeia 1986, no. 3 (August 4, 1986): 796. http://dx.doi.org/10.2307/1444962.

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48

Taşkavak, Ertan, Salim Can Akçınar, and Çağlayan İnanlı. "Rare occurrence of the Leatherback Sea Turtle, Dermochelys coriacea, in Izmir Bay, Aegean Sea, Turkey." Ege Journal of Fisheries and Aquatic Sciences 32, no. 1 (November 15, 2015): 51–52. http://dx.doi.org/10.12714/egejfas.2015.32.1.08.

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Patino-Martinez, Juan, Adolfo Marco, Liliana Quiñones, Elena Abella, Roberto Muriel Abad, and Javier Diéguez-Uribeondo. "How do hatcheries influence embryonic development of sea turtle eggs? Experimental analysis and isolation of microorganisms in leatherback turtle eggs." Journal of Experimental Zoology Part A: Ecological Genetics and Physiology 317A, no. 1 (October 21, 2011): 47–54. http://dx.doi.org/10.1002/jez.719.

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50

Margaritoulis, Dimitris N. "Captures and Strandings of the Leatherback Sea Turtle, Dermochelys coriacea, in Greece (1982-1984)." Journal of Herpetology 20, no. 3 (September 1986): 471. http://dx.doi.org/10.2307/1564521.

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Journal articles on the topic 'Leatherback turtle Leatherback turtle Sea turtles'

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