Let's Learn About Turtles
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												  Beach Dynamics and Impact of Armouring on Olive Ridley Sea Turtle (Lepidochelys Olivacea) Nesting at Gahirmatha Rookery of Odisha Coast, IndiaIndian Journal of Geo-Marine Sciences Vol. 45(2), February 2016, pp. 233-238 Beach dynamics and impact of armouring on olive ridley sea turtle (Lepidochelys olivacea) nesting at Gahirmatha rookery of Odisha coast, India Satyaranjan Behera1, 2, Basudev Tripathy3*, K. Sivakumar2, B.C. Choudhury2 1Odisha Biodiversity Board, Regional Plant Resource Centre Campus, Nayapalli, Bhubaneswar-15 2Wildlife Institute of India, Dehradun, PO Box 18, Chandrabani, Dehradun – 248 001, India. 3Zoological Survey of India, Prani Vigyan Bhawan, M-Block, New Alipore, Kolkata-700 053 (India) *[E. mail:[email protected]] Received 28 March 2014; revised 18 September 2014 Gahirmatha arribada beach are most dynamic and eroding at a faster rate over the years from 2008-09 to 2010-11, especially during the turtles breeding seasons. Impact of armouring cement tetrapod on olive ridley sea turtle nesting beach at Gahirmatha rookery of Odisha coast has also been reported in this study. This study documented the area of nesting beach has reduced from 0.07 km2to 0.06 km2. Due to a constraint of nesting space, turtles were forced to nest in the gap of cement tetrapods adjacent to the arribada beach and get entangled there, resulting into either injury or death. A total of 209 and 24 turtles were reported to be injured and dead due to placement of cement tetrapods in their nesting beach during 2008-09 and 2010-11 respectively. Olive ridley turtles in Odisha are now exposed to many problems other than fishing related casualty and precautionary measures need to be taken by the wildlife and forest authorities to safeguard the Olive ridleys and their nesting habitat at Gahirmatha.
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												  AN INTRODUCTION to Texas TurtlesTEXAS PARKS AND WILDLIFE AN INTRODUCTION TO Texas Turtles Mark Klym An Introduction to Texas Turtles Turtle, tortoise or terrapin? Many people get confused by these terms, often using them interchangeably. Texas has a single species of tortoise, the Texas tortoise (Gopherus berlanderi) and a single species of terrapin, the diamondback terrapin (Malaclemys terrapin). All of the remaining 28 species of the order Testudines found in Texas are called “turtles,” although some like the box turtles (Terrapene spp.) are highly terrestrial others are found only in marine (saltwater) settings. In some countries such as Great Britain or Australia, these terms are very specific and relate to the habit or habitat of the animal; in North America they are denoted using these definitions. Turtle: an aquatic or semi-aquatic animal with webbed feet. Tortoise: a terrestrial animal with clubbed feet, domed shell and generally inhabiting warmer regions. Whatever we call them, these animals are a unique tie to a period of earth’s history all but lost in the living world. Turtles are some of the oldest reptilian species on the earth, virtually unchanged in 200 million years or more! These slow-moving, tooth less, egg-laying creatures date back to the dinosaurs and still retain traits they used An Introduction to Texas Turtles | 1 to survive then. Although many turtles spend most of their lives in water, they are air-breathing animals and must come to the surface to breathe. If they spend all this time in water, why do we see them on logs, rocks and the shoreline so often? Unlike birds and mammals, turtles are ectothermic, or cold- blooded, meaning they rely on the temperature around them to regulate their body temperature.
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												  Background on Sea TurtlesBackground on Sea Turtles Five of the seven species of sea turtles call Virginia waters home between the months of April and November. All five species are listed on the U.S. List of Endangered and Threatened Wildlife and Plants and classified as either “Threatened” or “Endangered”. It is estimated that anywhere between five and ten thousand sea turtles enter the Chesapeake Bay during the spring and summer months. Of these the most common visitor is the loggerhead followed by the Kemp’s ridley, leatherback and green. The least common of the five species is the hawksbill. The Loggerhead is the largest hard-shelled sea turtle often reaching weights of 1000 lbs. However, the ones typically sighted in Virginia’s waters range in size from 50 to 300 lbs. The diet of the loggerhead is extensive including jellies, sponges, bivalves, gastropods, squid and shrimp. While visiting the Bay waters the loggerhead dines almost exclusively on horseshoe crabs. Virginia is the northern most nesting grounds for the loggerhead. Because the temperature of the nest dictates the sex of the turtle it is often thought that the few nests found in Virginia are producing predominately male offspring. Once the male turtles enter the water they will never return to land in their lifetime. Loggerheads are listed as a “Threatened” species. The Kemp’s ridley sea turtle is the second most frequent visitor in Virginia waters. It is the smallest of the species off Virginia’s coast reaching a maximum weight of just over 100 lbs. The specimens sited in Virginia are often less than 30 lbs.
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												  Turtles, All Marine Turtles, Have Been Documented Within the State’S BordersTurtle Only four species of turtles, all marine turtles, have been documented within the state’s borders. Terrestrial and freshwater aquatic species of turtles do not occur in Alaska. Marine turtles are occasional visitors to Alaska’s Gulf Coast waters and are considered a natural part of the state’s marine ecosystem. Between 1960 and 2007 there were 19 reports of leatherback sea turtles (Dermochelys coriacea), the world’s largest turtle. There have been 15 reports of Green sea turtles (Chelonia mydas). The other two are extremely rare, there have been three reports of Olive ridley sea turtles (Lepidochelys olivacea) and two reports of loggerhead sea turtles (Caretta caretta). Currently, all four species are listed as threatened or endangered under the U.S. Endangered Species Act. Prior to 1993, Alaska marine turtle sightings were mostly of live leatherback sea turtles; since then most observations have been of green sea turtle carcasses. At present, it is not possible to determine if this change is related to changes in oceanographic conditions, perhaps as the result of global warming, or to changes in the overall population size and distribution of these species. General description: Marine turtles are large, tropical/subtropical, thoroughly aquatic reptiles whose forelimbs or flippers are specially modified for swimming and are considerably larger than their hind limbs. Movements on land are awkward. Except for occasional basking by both sexes and egg-laying by females, turtles rarely come ashore. Turtles are among the longest-lived vertebrates. Although their age is often exaggerated, they probably live 50 to 100 years. Of the five recognized species of marine turtles, four (including the green sea turtle) belong to the family Cheloniidae.
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												  'Camouflage' Their Nests but Avoid Them and Create a Decoy TrailBuried treasure—marine turtles do not ‘disguise’ or royalsocietypublishing.org/journal/rsos ‘camouflage’ their nests but avoid them and create a Research Cite this article: Burns TJ, Thomson RR, McLaren decoy trail RA, Rawlinson J, McMillan E, Davidson H, Kennedy — MW. 2020 Buried treasure marine turtles do not † ‘disguise’ or ‘camouflage’ their nests but avoid Thomas J. Burns , Rory R. Thomson, Rosemary them and create a decoy trail. R. Soc. Open Sci. 7: 200327. A. McLaren, Jack Rawlinson, Euan McMillan, http://dx.doi.org/10.1098/rsos.200327 Hannah Davidson and Malcolm W. Kennedy Institute of Biodiversity, Animal Health and Comparative Medicine, and School of Life Sciences, Graham Kerr Building, College of Medical, Veterinary and Life Sciences, Received: 27 February 2020 University of Glasgow, Glasgow G12 8QQ, UK Accepted: 6 April 2020 TJB, 0000-0003-0408-8014; MWK, 0000-0002-0970-5264 After laying their eggs and refilling the egg chamber, sea Subject Category: turtles scatter sand extensively around the nest site. This is presumed to camouflage the nest, or optimize local conditions Organismal and Evolutionary Biology for egg development, but a consensus on its function is Subject Areas: lacking. We quantified activity and mapped the movements of hawksbill (Eretmochelys imbricata) and leatherback (Dermochelys behaviour coriacea) turtles during sand-scattering. For leatherbacks, we also recorded activity at each sand-scattering position. Keywords: For hawksbills, we recorded breathing rates during nesting as hawksbill turtle, Eretmochelys imbricata, leatherback an indicator of metabolic investment and compared with turtle, Dermochelys coriacea, nesting behaviour published values for leatherbacks. Temporal and inferred metabolic investment in sand-scattering was substantial for both species.
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												  Issue Number 118 October 2007 ISSN 0839-7708 in THISIssue Number 118 October 2007 Green turtle hatchling from Turkey with extra carapacial scutes (see pp. 6-8). Photo by O. Türkozan IN THIS ISSUE: Editorial: Conservation Conflicts, Conflicts of Interest, and Conflict Resolution: What Hopes for Marine Turtle Conservation?..........................................................................................L.M. Campbell Articles: From Hendrickson (1958) to Monroe & Limpus (1979) and Beyond: An Evaluation of the Turtle Barnacle Tubicinella cheloniae.........................................................A. Ross & M.G. Frick Nest relocation as a conservation strategy: looking from a different perspective...................O. Türkozan & C. Yılmaz Linking Micronesia and Southeast Asia: Palau Sea Turtle Satellite Tracking and Flipper Tag Returns......S. Klain et al. Morphometrics of the Green Turtle at the Atol das Rocas Marine Biological Reserve, Brazil...........A. Grossman et al. Notes: Epibionts of Olive Ridley Turtles Nesting at Playa Ceuta, Sinaloa, México...............................L. Angulo-Lozano et al. Self-Grooming by Loggerhead Turtles in Georgia, USA..........................................................M.G. Frick & G. McFall IUCN-MTSG Quarterly Report Announcements News & Legal Briefs Recent Publications Marine Turtle Newsletter No. 118, 2007 - Page 1 ISSN 0839-7708 Editors: Managing Editor: Lisa M. Campbell Matthew H. Godfrey Michael S. Coyne Nicholas School of the Environment NC Sea Turtle Project A321 LSRC, Box 90328 and Earth Sciences, Duke University NC Wildlife Resources Commission Nicholas School of the Environment 135 Duke Marine Lab Road 1507 Ann St. and Earth Sciences, Duke University Beaufort, NC 28516 USA Beaufort, NC 28516 USA Durham, NC 27708-0328 USA E-mail: [email protected] E-mail: [email protected] E-mail: [email protected] Fax: +1 252-504-7648 Fax: +1 919 684-8741 Founding Editor: Nicholas Mrosovsky University of Toronto, Canada Editorial Board: Brendan J.
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												  Reproductive Physiology of Nesting Leatherback Turtles (Dermochelys Coriacea) at Las Baulas National Park, Costa RicaChelolliall COllserwuioll (lnd Biology, 1996,2(2):230- 236 © 1996 by Chelonian Research Foundation Reproductive Physiology of Nesting Leatherback Turtles (Dermochelys coriacea) at Las Baulas National Park, Costa Rica i 2 3 4 DAVID C. ROSTAL , FRANK V. PALADIN0 , RHONDA M. PATTERSON , AND JAMES R. SPOTILA I Department of Biology, Georgia Southern Uni versity, Statesboro, Georgia 30460 USA [Fax: 912-681-0845; E-mail: [email protected]}; 2Department of Biology, Indiana-Purdue University, Fort Wayne, Indiana 46805 USA ; 3Department of Biology, Texas A&M University, College Station, Texas 77843 USA ; 4Department o{Bioscience and Biotechnology, Drexel University, Philadelphia, Pennsylvania 19104 USA ABSTRACT. - The reproductive physiology of nesting leatherback turtles (Dermochelys coriacea) was studied at Playa Grande, Costa Rica, from 1992 to 1994 during November, December, and January. Ultrasonography indicated that 82 % of nesting females had mature preovulatory ovaries in November, 40 % in December, and 23 % in January. Mean follicular diameter was 3.33 ±0.02 cm and did not vary significantly through the nesting season. Plasma testosterone and estradiol levels measured by radioimmunoassay correlated strongly with reproductive condition. No correlation, however, was observed between reproductive condition and plasma progesterone levels. Testoster one declined from 2245 ± 280 pglml at the beginning of the nesting cycle to 318 ± 89 pglml at the end of the nesting cycle. Estradiol declined in a similar manner. Plasma calcium levels were constant throughout the nesting cycle. Vitellogenesis appeared complete prior to the arrival of the female at the nesting beach. Dermochelys coriacea is a seasonal nester displaying unique variations (e.g., 9 to 10 day internesting interval, yolkless eggs) on the basic chelonian pattern.
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												  The Latest Record of the Leatherback Sea Turtle (Dermochelys Coriacea16 Coll. and Res. (2003) 16: 13-16 Coll. and Res. (2003) 16: 17-26 17 claw ending as knob; empodium divided, 5 rayed. without a short line on each side, admedian lines The Latest Record of the Leatherback Sea Turtle (Dermochelys with a semicircular line extending to lateral sides, Opisthosoma : dorsum with median ridge shorter and the 5-rayed empodium. coriacea) from Eastern Taiwan than submedian ridges, dorsally with about 51 rings, ventrally with about 53 microtuberculate Chun-Hsiang Chang1,2*, Chern-Mei Jang3, and Yen-Nien Cheng2 REFERENCES rings; 1st 3 dorsal annuli 9 long; lateral setae (c2) 10 long, Lt-Lt 44 apart, Lt\Vt1 38, Lt-Vt1 25; 1st 1Department of Biology, University College London, London WC1E 6BT, UK Keifer, H.H. 1977. Eriophyid studies C-13. ARS- ventral setae (d) 17 long, Vt1-Vt1 19 apart, 2Department of Geology, National Museum of Natural Science, Taichung, Taiwan 404 R.O.C. USDA, Washington, DC. 24pp. Vt1\Vt2 28, Vt1-Vt2 25; 2nd ventral setae (e) 17 3 Keifer, H.H. 1978. Eriophyid studies C-15. ARS- Department of Collection Management, National Museum of Natural Science, Taichung Taiwan 404 long, Vt2-Vt2 10 apart, Vt2\Vt3 40, Vt2-Vt3 38; USDA, Washington, DC. 24pp. R.O.C. 3rd ventral setae (f) 14 long, Vt3-Vt3 16 apart; Huang, K.W. 1999. The species and geographic accessory setae (h1) present. variation of eriophyoid mites on Yushania Coverflap: 19 wide, 12 long, with about 9 niitakayamensis of Taiwan. Proc. Symp. In (Received June 30, 2003; Accepted September 16, 2003) longitudinal ridges, genital setae (3a) 6 long, Gt- Insect Systematics and Evolution.
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												  Sea Turtles : the Importance of Sea Turtles to Marine EcosystemsPHOTO TIM CALVER WHY HEALTHY OCEANS NEED SEA TURTLES : THE IMPORTANCE OF SEA TURTLES TO MARINE ECOSYSTEMS Wilson, E.G., Miller, K.L., Allison, D. and Magliocca, M. oceana.org/seaturtles S E L T R U T Acknowledgements The authors would like to thank Karen Bjorndal for her review of this report. We would also like to thank The Streisand Foundation for their support of Oceana’s work to save sea turtles. PHOTO MICHAEL STUBBLEFIELD OCEANA | Protecting the World’s Oceans TABLE OF CONTENTS WHY HEALTHY OCEANS NEED SEA TURTLES 3 Executive Summary 4 U.S. Sea Turtles 5 Importance of Sea Turtles to Healthy Oceans 6 Maintaining Habitat Importance of Green Sea Turtles on Seagrass Beds Impact of Hawksbill Sea Turtles on Coral Reefs Benefit of Sea Turtles to Beach Dunes 9 Maintaining a Balanced Food Web Sea Turtles and Jellyfish Sea Turtles Provide Food for Fish 11 Nutrient Cycling Loggerheads Benefit Ocean Floor Ecosystems Sea Turtles Improve Nesting Beaches 12 Providing Habitat 14 The Risk of Ecological Extinction 15 Conclusions oceana.org/seaturtles 1 S E L T R U T PHOTO TIM CALVER 2 OCEANA | Protecting the World’s Oceans EXECUTIVE SUMMARY Sea turtles have played vital roles in maintaining the health of the world’s oceans for more than 100 million years. These roles range from maintaining productive coral reef ecosystems to transporting essential nutrients from the oceans to beaches and coastal dunes. Major changes have occurred in the oceans because sea turtles have been virtually eliminated from many areas of the globe. Commercial fishing, loss of nesting habitat and climate change are among the human-caused threats pushing sea turtles towards extinction.
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												  Morphological Variation in Leatherback (Dermochelys Coriacea) Hatchlings at Sandy Point National Wildlife Refuge, US Virgin IslandsVol. 41: 361–372, 2020 ENDANGERED SPECIES RESEARCH Published April 9 https://doi.org/10.3354/esr01030 Endang Species Res OPENPEN ACCESSCCESS Morphological variation in leatherback (Dermochelys coriacea) hatchlings at Sandy Point National Wildlife Refuge, US Virgin Islands Shreya M. Banerjee1,6,*, Amy Frey2, Carolyn M. Kurle3, Justin R. Perrault4,7, Kelly R. Stewart5 1Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92037, USA, ORCID: 0000-0003-1210-2162 2Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA 3Division of Biological Sciences, Ecology, Behavior, and Evolution Section, University of California, San Diego, La Jolla, CA 92093, USA, ORCID: 0000-0003-1121-9924 4Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA 5The Ocean Foundation, Washington, DC 20036, USA, ORCID: 0000-0002-8673-5192 6Present address: Department of Biology, Stanford University, Stanford, CA 94305, USA 7Present address: Loggerhead Marinelife Center, Juno Beach, FL 33408, USA, ORCID: 0000-0002-5046-6701 ABSTRACT: Understanding species’ mating systems provides important information about their ecology, life history, and behavior. Direct observations of mating behaviors can be challenging, but molecular techniques can reveal information about mating systems and paternal identity in difficult-to-observe species such as sea turtles. Genetic markers can be used to assess the pater- nity of a clutch and to assign hatchlings to a father. Leatherback turtles Dermochelys coriacea sometimes mate with multiple individuals, resulting in clutches with mixed paternity; however, the effects of multiple paternity on hatchling quality are unclear.
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												  Turtle Tracks Miami-Dade County Marine Extension ServiceTurtle Tracks Miami-Dade County Marine Extension Service Florida Sea Grant Program DISTURBING A SEA TURTLE NEST IS A VIOLATION 4 OF STATE AND FEDERAL LAWS. 2 TURTLE TRACKS What To Do If You See A Turtle 1 3 SEA TURTLE CONSERVATION IN MIAMI-DADE COUNTY If you observe an adult sea turtle or hatchling sea turtles on the beach, please adhere to the following rules and guidelines: 1. It is normal for sea turtles to be crawling on the beach on summer nights. DO NOT report normal crawling or nesting (digging or laying eggs) to the Florida Marine Patrol unless the turtle is in a dangerous situation or has wandered off the beach. 1. Leatherback (on a road, in parking lot, etc.) 2. Stay away from crawling or nesting sea turtles. Although the 2. Kemp’s Ridley urge to observe closely will be great, please resist. Nesting is a 3. Green critical stage in the sea turtle’s life cycle. Please leave them 4. Loggerhead undisturbed. U.S. GOVERNMENTPRINTINGOFFICE: 1999-557-736 3. DO REPORT all stranded (dead or injured) turtles to the This information is a cooperative effort on behalf of the following organizations to Florida Marine Patrol. help residents of Miami-Dade County learn about sea turtle conservation efforts in 4. NEVER handle hatchling sea turtles. If you observe hatchlings this coastal region of the state. wandering away from the ocean or on the beach, call: NATIONAL Florida Marine Pat r ol 1-800- DIAL-FMP (3425-367) SAVE THE SEATURTLE FOUNDATION MIAMI-DADE COUNTY SEA TURTLE CONSERVATION PROGRAM 4419 West Tradewinds Avenue "To Protect Endangered or Threatened Marine Turtles for Fort Lauderdale, Floirda 33308 Future Generations" Phone: 954-351-9333 efore 1980, there was no documented sea Fax: 954-351-5530 Toll Free: 877-Turtle3 turtle activity in Mia m i - D ade County, due B mainly to the lack of an adequate beach-nesting Information has been drawn from “Sea Turtle Conservation Program“, a publication of the Broward County Department of Planning and Environmental Protection, habitat.
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												  OLIVE RIDLEY SEA TURTLE (Lepidochelys Olivacea)OLIVE RIDLEY SEA TURTLE (Lepidochelys olivacea) General Characteristics The name of the olive ridley originates from the olive color of the adult’s carapace. Its head is triangular in shape, measuring up to 13 cm (5.1 in.) wide, with two pairs of prefrontal scales. Their carapace is circular and flat with a uniquely high and variable number (six to nine pairs) of costal scutes, and ranges from olive green to dark grey in color. The plastron is cream colored and has a small and distinct pore close to the rear margin of each of the four inframarginal scutes. Its body is deeper than the Kemp’s Ridley (L. kempii), which is found primarily in the Gulf of Mexico and along the eastern coast of the USA. Size The olive ridley is one of the smallest sea turtles; the length of the carapaces is approximately 65 cm (2 ft.) and reaches up to 50 kg. (110 lbs.). Both the front and rear flippers have one, or sometimes two, claws. Habitat Olive ridleys are found throughout the tropical waters of the Pacific, Indian and southern Atlantic Oceans. In the eastern Pacific they range from Mexico to Colombia and are sometimes found off the southwestern coast of the United States. Non-nesting individuals are often found in Isla de Margarita (Venezuela) and Trinidad & Tobago; however, they rarely go deeper into the Caribbean. They typically forage offshore in surface waters, primarily in bays and estuaries. They may dive to depths of 150 meters (500 ft.) to feed on bottom- dwelling crustaceans. Diet Their large and powerful jaws are adapted to their diet of mostly fish, mussels and crustaceans, particularly shrimp.