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Sample records for ridley lepidochelys kempii

  1. Head-started Kemp’s ridley turtle (Lepidochelys kempii) nest recorded in Florida: Possible implications

    USGS Publications Warehouse

    Shaver, Donna J.; Lamont, Margaret M.; Maxwell, Sharon; Walker, Jennifer Shelby; Dillingham, Ted

    2016-01-01

    A head-started Kemp’s ridley sea turtle (Lepidochelys kempii) was documented nesting on South Walton Beach, Florida on 25 May 2015. This record supports the possibility that exposure to Florida waters after being held in captivity through 1–3 yrs of age during the head-starting process may have influenced future nest site selection of this and perhaps other Kemp’s ridley turtles. Such findings could have important ramifications for marine water experimentation and release site selection for turtles that have been reared in captivity.

  2. The ontogeny of morphological defenses in Kemp's ridley (Lepidochelys kempii) and loggerhead (Caretta caretta) sea turtles.

    PubMed

    Salmon, Michael; Higgins, Benjamin; Stewart, Joshua; Wyneken, Jeanette

    2015-08-01

    Marine turtles are large reptiles that compensate for high juvenile mortality by producing hundreds of hatchlings during a long reproductive lifespan. Most hatchlings are taken by predators during their migration to, and while resident in, the open ocean. Their survival depends upon crypticity, minimizing movement to avoid detection, and foraging efficiently to grow to a size too difficult for predators to either handle or swallow. While these behavioral antipredator tactics are known, changes in morphology accompanying growth may also improve survival prospects. These have been only superficially described in the literature. Here, we compare the similarities and differences in presumed morphological defenses of growing loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) posthatchlings, related species that differ in growth rate, timing of habitat shift (the return from oceanic to neritic locations), and size at maturity. In both species, vertebral spination and carapace widening increase disproportionally as small turtles grow, but later in ontogeny, the spines regress, sooner in ridley than in loggerhead turtles. Carapace widening occurs in both species but loggerheads are always longer than they are wide whereas in Kemp's ridley turtles, the carapace becomes as wide as long. Our analysis indicates that these changes are unrelated to when each species shifts habitat but are related to turtle size. We hypothesize that the spines function in small turtles as an early defense against gape-limited predators, but changes in body shape function throughout ontogeny-initially to make small turtles too wide to swallow and later by presenting an almost flat and hardened surface that large predators (such as a sharks) are unable to grasp. The extremely wide carapace of the Kemp's ridley may compensate for its smaller adult size (and presumed greater vulnerability) than the loggerhead.

  3. Assessment of ground transportation stress in juvenile Kemp's ridley sea turtles (Lepidochelys kempii).

    PubMed

    Hunt, Kathleen E; Innis, Charles J; Kennedy, Adam E; McNally, Kerry L; Davis, Deborah G; Burgess, Elizabeth A; Merigo, Constance

    2016-01-01

    Sea turtle rehabilitation centres frequently transport sea turtles for long distances to move animals between centres or to release them at beaches, yet there is little information on the possible effects of transportation-related stress ('transport stress') on sea turtles. To assess whether transport stress is a clinically relevant concern for endangered Kemp's ridley sea turtles (Lepidochelys kempii), we obtained pre-transport and post-transport plasma samples from 26 juvenile Kemp's ridley sea turtles that were transported for 13 h (n = 15 turtles) or 26 h (n = 11 turtles) by truck for release at beaches. To control for effects of handling, food restriction and time of day, the same turtles were also studied on 'control days' 2 weeks prior to transport, i.e. with two samples taken to mimic pre-transport and post-transport timing, but without transportation. Blood samples were analysed for nine clinical health measures (pH, pCO2, pO2, HCO3, sodium, potassium, ionized calcium, lactate and haematocrit) and four 'stress-associated' parameters (corticosterone, glucose, white blood cell count and heterophil-to-lymphocyte ratio). Vital signs (heart rate, respiratory rate and cloacal temperature) were also monitored. Corticosterone and glucose showed pronounced elevations due specifically to transportation; for corticosterone, this elevation was significant only for the longer transport duration, whereas glucose increased significantly after both transport durations. However, clinical health measures and vital signs showed minimal or no changes in response to any sampling event (with or without transport), and all turtles appeared to be in good clinical health after both transport durations. Thus, transportation elicits a mild, but detectable, adrenal stress response that is more pronounced during longer durations of transport; nonetheless, Kemp's ridley sea turtles can tolerate ground transportation of up to 26 h in good health. These results are likely

  4. Assessment of ground transportation stress in juvenile Kemp’s ridley sea turtles (Lepidochelys kempii)

    PubMed Central

    Hunt, Kathleen E.; Innis, Charles J.; Kennedy, Adam E.; McNally, Kerry L.; Davis, Deborah G.; Burgess, Elizabeth A.; Merigo, Constance

    2016-01-01

    Sea turtle rehabilitation centres frequently transport sea turtles for long distances to move animals between centres or to release them at beaches, yet there is little information on the possible effects of transportation-related stress (‘transport stress’) on sea turtles. To assess whether transport stress is a clinically relevant concern for endangered Kemp’s ridley sea turtles (Lepidochelys kempii), we obtained pre-transport and post-transport plasma samples from 26 juvenile Kemp’s ridley sea turtles that were transported for 13 h (n = 15 turtles) or 26 h (n = 11 turtles) by truck for release at beaches. To control for effects of handling, food restriction and time of day, the same turtles were also studied on ‘control days’ 2 weeks prior to transport, i.e. with two samples taken to mimic pre-transport and post-transport timing, but without transportation. Blood samples were analysed for nine clinical health measures (pH, pCO2, pO2, HCO3, sodium, potassium, ionized calcium, lactate and haematocrit) and four ‘stress-associated’ parameters (corticosterone, glucose, white blood cell count and heterophil-to-lymphocyte ratio). Vital signs (heart rate, respiratory rate and cloacal temperature) were also monitored. Corticosterone and glucose showed pronounced elevations due specifically to transportation; for corticosterone, this elevation was significant only for the longer transport duration, whereas glucose increased significantly after both transport durations. However, clinical health measures and vital signs showed minimal or no changes in response to any sampling event (with or without transport), and all turtles appeared to be in good clinical health after both transport durations. Thus, transportation elicits a mild, but detectable, adrenal stress response that is more pronounced during longer durations of transport; nonetheless, Kemp’s ridley sea turtles can tolerate ground transportation of up to 26 h in good health. These

  5. Organohalogen contaminants in blood of Kemp's ridley (Lepidochelys kempii) and green sea turtles (Chelonia mydas) from the Gulf of Mexico.

    PubMed

    Swarthout, Robert F; Keller, Jennifer M; Peden-Adams, Margie; Landry, Andre M; Fair, Patricia A; Kucklick, John R

    2010-02-01

    The threat that exposure to organohalogen (OH) contaminants poses to endangered populations of Kemp's ridley (Lepidochelys kempii) and green sea turtles (Chelonia mydas) is not well understood, partly because few OH data are available. Blood samples from live juvenile and sub-adult L. kempii (n = 46) and C. mydas (n = 9) from the Gulf of Mexico and from L. kempii from the southeastern US coast (n = 3) were extracted using microwave-assisted extraction, and analyzed by large volume injection gas chromatography-mass spectrometry for 85 polychlorinated biphenyls (PCBs), 25 organochlorine pesticides (OCPs) and 27 polybrominated diphenyl ethers (PBDEs). Plasma chemistries, hematology and immune responses were also assessed. Concentrations of SigmaPCBs (geometric mean, range: 3190 pg g(-1), 227-21590 pg g(-1) blood), SigmaDDTs (geometric mean, range: 541 pg g(-1), 161-4310 pg g(-1) blood) and OCPs in L. kempii from the Gulf were comparable to those reported in L. kempii from the Atlantic. SigmaPBDEs were detected in all samples (geometric mean, range: 146 pg g(-1), 19.5-1450 pg g(-1) blood), with PBDE 47, 99, 100, 153 and 154 being the predominant congeners. SigmaPCBs, SigmaDDTs and Sigmachlordanes were one order of magnitude lower in green turtles, and SigmaPBDE concentrations were lower by half due to trophic level differences. L. kempii from the southeast USA had higher percentages of highly chlorinated PCBs indicating exposure to Aroclor 1268. Blood urea nitrogen was positively correlated to Sigmachlordanes, and SigmaPCBs were inversely correlated to creatine phosphokinase in L. kempii. These data help establish baseline contaminant concentrations in live L. kempii and C. mydas.

  6. Corticosterone and thyroxine in cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii).

    PubMed

    Hunt, Kathleen E; Innis, Charles; Rolland, Rosalind M

    2012-09-01

    Kemp's ridley sea turtles (Lepidochelys kempii), a critically endangered species, frequently strand on the shores of Cape Cod (Massachusetts, USA) in late autumn in a state of "cold-stunning" exhibiting low body temperature and related clinical issues. Stranded turtles are transported to the New England Aquarium (Boston, Massachusetts, USA) for treatment and rehabilitation. This study tested the hypothesis that cold-stunned sea turtles might exhibit high corticosterone ("stress hormone") or low thyroxine (which is often affected by temperature), or both, and that monitoring of both hormones may be useful for assessing recovery. In a retrospective analysis, 87 archived plasma samples were assayed from 56 cold-stunned juvenile Kemp's ridley sea turtles for corticosterone and free thyroxine (fT4). Upon admission, mean corticosterone was the highest yet reported for a population of sea turtles (39.3 +/- 2.5 ng/ml; mean +/- standard error of the mean [SEM]) and fT4 was usually undetectable. On admission, corticosterone was negatively correlated with white blood cell count but was not correlated with blood glucose. There were no differences in either hormone between survivors and nonsurvivors on admission. After 18+ days in recovery, surviving turtles' corticosterone dropped significantly to levels typical of baseline in other species (0.9 +/- 1.0 ng/ml) while fT4 increased significantly (1.3 +/- 1.5 pg/ml). During recovery, corticosterone was positively correlated with blood glucose and was not correlated with white blood cell count. Turtles that showed persistent deficits in feeding, activity, or both during recovery had significantly lower fT4 than did turtles with no such deficits. The "high corticosterone, low fT4" endocrine profile seen on admission may be a useful marker of cold-stunning in this and other species. Further studies are necessary to determine whether low thyroid hormones play a causal role in deficits in feeding and activity during recovery

  7. Surgical removal of an abscess associated with Fusarium solani from a Kemp's ridley sea turtle (Lepidochelys kempii).

    PubMed

    Williams, Sea Rogers; Sims, Michele A; Roth-Johnson, Lois; Wickes, Brian

    2012-06-01

    A cold-stunned Kemp's ridley sea turtle, Lepidochelys kempii, developed an abscess associated with Fusarium solani, Vibrio alginolyticus, and a Shewenalla species after receiving a bite wound to the front flipper during rehabilitation. The lesion failed to respond to medical therapy and was treated successfully with surgery. Histopathology of the excised tissue demonstrated septic heterophilic inflammation with necrosis and granulation tissue, fungal elements, and bacteria, despite appropriate antimicrobial therapy. Variably thick bands of dense collagenous tissue partially surrounded affected areas which might have limited drug penetration into the tissue. Postoperative healing and eventual releases were uneventful. This is the first report of surgical treatment of cutaneous Fusarium infection in a sea turtle and supports surgery as an effective treatment for a fungal abscess in a reptile.

  8. Pathologic and parasitologic findings of cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii) stranded on Cape Cod, Massachusetts, 2001-2006.

    PubMed

    Innis, Charles; Nyaoke, Akinyi C; Williams, C Rogers; Dunnigan, Bridget; Merigo, Constance; Woodward, Denise L; Weber, E Scott; Frasca, Salvatore

    2009-07-01

    Necropsy reports for 28 stranded, cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii) that died between 2001 and 2006 were reviewed retrospectively. Gross and microscopic lesions were compiled to describe the pathologic and parasitologic findings in turtles that were found freshly dead on the beach or that died within 48 hr of stranding. Anatomic lesions of varying severity were identified in each of the examined turtles and were identified in tissues of the alimentary, respiratory, integumentary, nervous and sensory, and urogenital systems in order of decreasing frequency. Necrotizing enterocolitis and bacterial or fungal pneumonia were the most frequently encountered lesions that were considered clinically significant. Parasites and parasitic lesions were identified primarily in tissues of the alimentary system and included intestinal cestodiasis and parasitic granulomas containing larval cestodes or nematodes. Postlarval cestodes were also found in the coelom of two turtles. In many cases, the extent and severity of lesions were judged to be insufficient to have solely caused mortality, suggesting that additional factors such as metabolic, respiratory, and electrolyte derangements; hypothermia; and drowning may be important proximate causes of death in cold-stunned turtles. Results of this study provide insight into pathologic conditions that may be of clinical relevance to rehabilitation efforts for cold-stunned sea turtles.

  9. Development and evaluation of three mortality prediction indices for cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii)

    PubMed Central

    Stacy, N. I.; Innis, C. J.; Hernandez, J. A.

    2013-01-01

    Kemp's ridley sea turtle is an endangered species found in the Gulf of Mexico and along the east coast of the USA. Cold-stunned Kemp's ridley turtles are often found stranded on beaches of Massachusetts and New York in November and December each year. When found alive, turtles are transported to rehabilitation centres for evaluation and treatment. Blood gas and chemistry analytes of major clinical relevance in sea turtles were selected to develop mortality prediction indices (MPI)s. Testing the diagnostic performance of various combinations of blood gas and chemistry analytes by receiver operating characteristics (ROC) analysis resulted in the development of three mortality prediction indices. The sensitivity and specificity of the best performing MPI (based on three blood analytes: pH, pO2, and potassium) was 88 and 80%, respectively. Using ROC analysis, the area under the curve = 0.896 (95% confidence interval = 0.83–0.94). The use of validated MPIs based on four blood analytes (pH, pCO2, pO2, and potassium) could be useful for better diagnosis, treatment, and prognosis of cold-stunned sea turtles when admitted to rehabilitation facilities. PMID:27293587

  10. The Effects of Feeding on Hematological and Plasma Biochemical Profiles in Green (Chelonia mydas) and Kemp's Ridley (Lepidochelys kempii) Sea Turtles.

    PubMed

    Anderson, Eric T; Minter, Larry J; Clarke, Elsburgh O; Mroch, Raymond M; Beasley, Jean F; Harms, Craig A

    2011-01-01

    In mammals, lipemic blood from sampling too soon after an animal feeds can have substantial effects on biochemical values. Plasma biochemical values in reptiles may be affected by species, age, season, and nutritional state. However, fasting status is not routinely considered when sampling reptile blood. In this paper, we evaluated 2-hour postprandial blood collection in two sea turtle species to investigate the effects of feeding on hematological and plasma biochemical values. Feeding had no significant effects on hematological values in either species, nor did it have an effect on plasma biochemistry values in Kemp's ridley sea turtles. In postprandial green turtles, total protein, albumin, ALP, AST, ALT, amylase, and cholesterol increased significantly, and chloride decreased significantly. Although statistically significant changes were observed, the median percent differences between pre- and postprandial values did not exceed 10% for any of these analytes and would not likely alter the clinical interpretation.

  11. 76 FR 58781 - Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-22

    ... Plans; Recovery Plan for the Kemp's Ridley Sea Turtle AGENCY: National Marine Fisheries Service (NMFS...- National Recovery Plan (Recovery Plan) for the Kemp's Ridley Sea Turtle (Lepidochelys kempii). The Recovery...: The Bi-National Recovery Plan for the Kemp's Ridley Sea Turtle (Lepidochelys kempii) is available...

  12. 75 FR 25840 - Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-10

    ... Plans; Recovery Plan for the Kemp's Ridley Sea Turtle AGENCIES: National Marine Fisheries Service (NMFS... Ridley Sea Turtle (Lepidochelys kempii). The Kemp's Ridley Recovery Plan is a bi-national plan developed... and interested parties to assist in the recovery of loggerhead turtles. The Plan...

  13. Ultrastructure and characteristics of eggshells of the olive ridley turtle (Lepidochelys olivacea) from Gahirmatha, India.

    PubMed

    Sahoo, G; Mohapatra, B K; Sahoo, R K; Mohanty-Hejmadi, P

    1996-01-01

    The structure of a chelonian eggshell is of prime importance for the developing embryo. It acts as a protective covering as well as mediator in the exchange of heat and water. The fresh eggshell of the olive ridley (Lepidochelys olivacea) turtle displays a variety of structural forms in their aragonite framework. Its netted substrate, loose texture and poorly organised crystallites favour the easy exchange of air and water during its development. The shell consists mostly of calcium in carbonate form and K, Mg, Fe, Ni, Pb, Zn, Co, Cr, Cu, Mn and Cd in traces. Ba and Sr in traces are also a feature of the thermal analysis graph. Phosphorous was not detected in the shell and its absence eliminates an earlier suggestion of it being a key factor in the development of aragonite crystals in the inorganic structure of marine turtle eggshells. Its combustion characteristics, which have not been previously reported, are recorded.

  14. Energetics during hatchling dispersal of the olive ridley turtle Lepidochelys olivacea using doubly labeled water.

    PubMed

    Clusella Trullas, Susana; Spotila, James R; Paladino, Frank V

    2006-01-01

    Studies of metabolism are central to the understanding of the ecology, behavior, and evolution of reptiles. This study focuses on one phase of the sea turtle life cycle, hatchling dispersal, and gives insight into energetic constraints that dispersal imposes on hatchlings. Hatchling dispersal is an energetically expensive phase in the life cycle of the olive ridley turtle Lepidochelys olivacea. Field metabolic rates (FMRs), determined using the doubly labeled water (DLW) method, for L. olivacea hatchlings digging out of their nest chamber, crawling at the sand surface, and swimming were five, four, and seven times, respectively, the resting metabolic rate (RMR). The cost of swimming was 1.5 and 1.8 times the cost of the digging and crawling phases, respectively, and we estimated that if L. olivacea hatchlings swim at frenzy levels, they can rely on yolk reserves to supply energy for only 3-6 d once they reach the ocean. We compared our RMR and FMR values by establishing an interspecific RMR mass-scaling relationship for a wide range of species in the order Testudines and found a scaling exponent of 1.06. This study demonstrates the feasibility of using the DLW method to estimate energetic costs of free-living sea turtle hatchlings and emphasizes the need for metabolic studies in various life-history stages.

  15. Seasonal reproductive cycle of the Kemp's ridley sea turtle (Lepidochelys kempi).

    PubMed

    Rostal, D C; Owens, D W; Grumbles, J S; MacKenzie, D S; Amoss, M S

    1998-02-01

    The seasonal reproductive cycle of the Kemp's ridley sea turtle (Lepidochelys kempi) was studied under seminatural conditions at the Cayman Turtle Farm, Grand Cayman, British West Indies, from June 1987 to July 1988. Male L. kempi displayed a prenuptial rise in serum testosterone 4 to 5 months prior to the mating period (March). Male testosterone then declined sharply during the mating period. Female L. kempi also displayed a prenuptial rise in serum testosterone, estradiol, and total calcium 4 to 6 months prior to the mating period (March). Female testosterone and estradiol declined during the nesting period (April to July) immediately following the mating period (March). Elevated levels in female estradiol and total calcium corresponded with the period of vitellogenesis as determined from gel electrophoresis and ultrasonography. Serum thyroxine also fluctuated seasonally with elevated levels observed in females associated with the period of vitellogenesis. L. kempi displayed a distinct seasonal reproductive cycle in captivity. Nesting in the captive study group corresponded with nesting in the wild population at Rancho Nuevo, Mexico (April to July). Female endocrine cycles during the nesting period were similar to those observed in the wild population.

  16. The use of spirometry to evaluate pulmonary function in olive ridley sea turtles (Lepidochelys olivacea) with positive buoyancy disorders.

    PubMed

    Schmitt, Todd L; Munns, Suzanne; Adams, Lance; Hicks, James

    2013-09-01

    This study utilized computed spirometry to compare the pulmonary function of two stranded olive ridley sea turtles (Lepidochelys olivacea) presenting with a positive buoyancy disorder with two healthy captive olive ridley sea turtles held in a large public aquarium. Pulmonary function test (PFT) measurements demonstrated that the metabolic cost of breathing was much greater for animals admitted with positive buoyancy than for the normal sea turtles. Positively buoyant turtles had higher tidal volumes and significantly lower breathing-frequency patterns with significantly higher expiration rates, typical of gasp-type breathing. The resulting higher energetic cost of breathing in the diseased turtles may have a significant impact on their long-term survival. The findings represent a method for clinical respiratory function analysis for an individual animal to assist with diagnosis, therapy, and prognosis. This is the first study, to our knowledge, to evaluate objectively sea turtles presenting with positive buoyancy and respiratory disease using pulmonary function tests.

  17. Effects of acute fresh water exposure on water flux rates and osmotic responses in Kemp's ridley sea turtles (Lepidochelys kempi).

    PubMed

    Ortiz, R M; Patterson, R M; Wade, C E; Byers, F M

    2000-09-01

    Water flux rates and osmotic responses of Kemp's Ridley sea turtles (Lepidochelys kempi) acutely exposed to fresh water were quantified. Salt-water adapted turtles were exposed to fresh water for 4 d before being returned to salt water. During the initial salt water phase, absolute and relative water flux rates were 1.2+/-0.1 l d(-1) and 123.0+/-6.8 ml kg(-1) d(-1), respectively. When turtles were exposed to fresh water, rates increased by approximately 30%. Upon return to salt water, rates decreased to original levels. Plasma osmolality, Na(+), K(+), and Cl(-) decreased during exposure to fresh water, and subsequently increased during the return to salt water. The Na(+):K(+) ratio was elevated during the fresh water phase and subsequently decreased upon return to salt water. Aldosterone and corticosterone were not altered during exposure to fresh water. Elevated water flux rates during fresh water exposure reflected an increase in water consumption, resulting in a decrease in ionic and osmotic concentrations. The lack of a change in adrenocorticoids to acute fresh water exposure suggests that adrenal responsiveness to an hypo-osmotic environment may be delayed in marine turtles when compared to marine mammals.

  18. Effects of acute fresh water exposure on water flux rates and osmotic responses in Kemp's ridley sea turtles (Lepidochelys kempi)

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Patterson, R. M.; Wade, C. E.; Byers, F. M.

    2000-01-01

    Water flux rates and osmotic responses of Kemp's Ridley sea turtles (Lepidochelys kempi) acutely exposed to fresh water were quantified. Salt-water adapted turtles were exposed to fresh water for 4 d before being returned to salt water. During the initial salt water phase, absolute and relative water flux rates were 1.2+/-0.1 l d(-1) and 123.0+/-6.8 ml kg(-1) d(-1), respectively. When turtles were exposed to fresh water, rates increased by approximately 30%. Upon return to salt water, rates decreased to original levels. Plasma osmolality, Na(+), K(+), and Cl(-) decreased during exposure to fresh water, and subsequently increased during the return to salt water. The Na(+):K(+) ratio was elevated during the fresh water phase and subsequently decreased upon return to salt water. Aldosterone and corticosterone were not altered during exposure to fresh water. Elevated water flux rates during fresh water exposure reflected an increase in water consumption, resulting in a decrease in ionic and osmotic concentrations. The lack of a change in adrenocorticoids to acute fresh water exposure suggests that adrenal responsiveness to an hypo-osmotic environment may be delayed in marine turtles when compared to marine mammals.

  19. Metals and metalloids in whole blood and tissues of Olive Ridley turtles (Lepidochelys olivacea) from La Escobilla Beach (Oaxaca, Mexico).

    PubMed

    Cortés-Gómez, Adriana A; Fuentes-Mascorro, Gisela; Romero, Diego

    2014-12-15

    Concentrations of eight metals and metalloids (Pb, Cd, Cu, Zn, Mn, Se, Ni and As) were evaluated from 41 nesting females (blood) and 13 dead (tissues) Olive Ridley turtles (Lepidochelys olivacea), a species classified as vulnerable and also listed in Appendix I of the Convention of International Trade in Endangered Species (CITES). The mean blood, liver and kidney lead concentration were 0.02 ± 0.01, 0.11 ± 0.08 and 0.06 ± 0.03 μ gg(-1) ww respectively, values lower than other turtle species and locations, which it could be due to the gradual disuse of leaded gasoline in Mexico and Central America since the 1990s. Mean concentration of cadmium was 0.17 ± 0.08 (blood), 82.88 ± 36.65 (liver) and 150.88 ± 110.9 9μg g(-1) (kidney). To our knowledge, the mean renal cadmium levels found is the highest ever reported worldwide for any sea turtle species, while other six elements showed a concentration similar to other studies in sea turtles.

  20. Predicted sex ratio of juvenile Kemp's Ridley sea turtles captured near Steinhatchee, Florida

    USGS Publications Warehouse

    Geis, A.A.; Barichivich, W.J.; Wibbels, T.; Coyne, M.; Landry, A.M.; Owens, D.

    2005-01-01

    The Kemp's Ridley (Lepidochelys kempii) is one of the most endangered sea turtles in the world, and it possesses temperature-dependent sex determination (TSD). Sex ratios produced under TSD can vary widely and can affect the reproductive ecology of a population. Therefore, sex ratios produced from TSD are of ecological and conservation interest. The current study validated and utilized a testosterone radioimmunoassay (RIA) to examine the sex ratio of juvenile Kemp's Ridleys inhabiting the waters near Steinhatchee, Florida. Testosterone levels were measured in blood samples collected from juvenile Kemp's Ridleys captured over a three-year period. Results of this study indicate that a significant female bias (approximately 3.7:1) occurs in the aggregation of juvenile Kemp's Ridleys inhabiting the waters near Steinhatchee.

  1. Diatoms and Other Epibionts Associated with Olive Ridley (Lepidochelys olivacea) Sea Turtles from the Pacific Coast of Costa Rica

    PubMed Central

    Majewska, Roksana; Santoro, Mario; Bolaños, Federico; Chaves, Gerardo; De Stefano, Mario

    2015-01-01

    Although the sea turtles have long been familiar and even iconic to marine biologists, many aspects of their ecology remain unaddressed. The present study is the first of the epizoic diatom community covering the olive ridley turtle’s (Lepidochelys olivacea) carapace and the first describing diatoms living on sea turtles in general, with the primary objective of providing detailed information on turtle epibiotic associations. Samples of turtle carapace including the associated diatom biofilm and epizoic macro-fauna were collected from Ostional beach (9° 59´ 23.7´´ N 85° 41´ 52.6´´ W), Costa Rica, during the arribada event in October 2013. A complex diatom community was present in every sample. In total, 11 macro-faunal and 21 diatom taxa were recorded. Amongst diatoms, the most numerous were erect (Achnanthes spp., Tripterion spp.) and motile (Haslea sp., Navicula spp., Nitzschia spp., Proschkinia sp.) forms, followed by adnate Amphora spp., while the most common macro-faunal species was Stomatolepas elegans (Cirripedia). Diatom densities ranged from 8179 ± 750 to 27685 ± 4885 cells mm-2. Epizoic microalgae were either partly immersed or entirely encapsulated within an exopolymeric coat. The relatively low diatom species number, stable species composition and low inter-sample dissimilarities (14.4% on average) may indicate a mutualistic relationship between the epibiont and the basibiont. Dispersal of sea turtle diatoms is probably highly restricted and similar studies will help to understand both diatom diversity, evolution and biogeography, and sea turtle ecology and foraging strategies. PMID:26083535

  2. Diatoms and Other Epibionts Associated with Olive Ridley (Lepidochelys olivacea) Sea Turtles from the Pacific Coast of Costa Rica.

    PubMed

    Majewska, Roksana; Santoro, Mario; Bolaños, Federico; Chaves, Gerardo; De Stefano, Mario

    2015-01-01

    Although the sea turtles have long been familiar and even iconic to marine biologists, many aspects of their ecology remain unaddressed. The present study is the first of the epizoic diatom community covering the olive ridley turtle's (Lepidochelys olivacea) carapace and the first describing diatoms living on sea turtles in general, with the primary objective of providing detailed information on turtle epibiotic associations. Samples of turtle carapace including the associated diatom biofilm and epizoic macro-fauna were collected from Ostional beach (9° 59´ 23.7´´ N 85° 41´ 52.6´´ W), Costa Rica, during the arribada event in October 2013. A complex diatom community was present in every sample. In total, 11 macro-faunal and 21 diatom taxa were recorded. Amongst diatoms, the most numerous were erect (Achnanthes spp., Tripterion spp.) and motile (Haslea sp., Navicula spp., Nitzschia spp., Proschkinia sp.) forms, followed by adnate Amphora spp., while the most common macro-faunal species was Stomatolepas elegans (Cirripedia). Diatom densities ranged from 8179 ± 750 to 27685 ± 4885 cells mm-2. Epizoic microalgae were either partly immersed or entirely encapsulated within an exopolymeric coat. The relatively low diatom species number, stable species composition and low inter-sample dissimilarities (14.4% on average) may indicate a mutualistic relationship between the epibiont and the basibiont. Dispersal of sea turtle diatoms is probably highly restricted and similar studies will help to understand both diatom diversity, evolution and biogeography, and sea turtle ecology and foraging strategies.

  3. The influence of oceanographic features on the foraging behavior of the olive ridley sea turtle Lepidochelys olivacea along the Guiana coast

    NASA Astrophysics Data System (ADS)

    Chambault, Philippine; de Thoisy, Benoît; Heerah, Karine; Conchon, Anna; Barrioz, Sébastien; Dos Reis, Virginie; Berzins, Rachel; Kelle, Laurent; Picard, Baptiste; Roquet, Fabien; Le Maho, Yvon; Chevallier, Damien

    2016-03-01

    The circulation in the Western Equatorial Atlantic is characterized by a highly dynamic mesoscale activity that shapes the Guiana continental shelf. Olive ridley sea turtles (Lepidochelys olivacea) nesting in French Guiana cross this turbulent environment during their post-nesting migration. We studied how oceanographic and biological conditions drove the foraging behavior of 18 adult females, using satellite telemetry, remote sensing data (sea surface temperature, sea surface height, current velocity and euphotic depth), simulations of micronekton biomass (pelagic organisms) and in situ records (water temperature and salinity). The occurrence of foraging events throughout migration was located using Residence Time analysis, while an innovative proxy of the hunting time within a dive was used to identify and quantify foraging events during dives. Olive ridleys migrated northwestwards using the Guiana current and remained on the continental shelf at the edge of eddies formed by the North Brazil retroflection, an area characterized by low turbulence and high micronekton biomass. They performed mainly pelagic dives, hunting for an average 77% of their time. Hunting time within a dive increased with shallower euphotic depth and with lower water temperatures, and mean hunting depth increased with deeper thermocline. This is the first study to quantify foraging activity within dives in olive ridleys, and reveals the crucial role played by the thermocline on the foraging behavior of this carnivorous species. This study also provides novel and detailed data describing how turtles actively use oceanographic structures during post-nesting migration.

  4. The Distribution and Conservation Status of Green Turtles (Chelonia mydas) and Olive Ridley Turtles (Lepidochelys olivacea) on Pulau Pinang beaches (Malaysia), 1995-2009.

    PubMed

    Salleh, Sarahaizad Mohd; Yobe, Mansor; Sah, Shahrul Anuar Mohd

    2012-05-01

    The Green Turtle (Chelonia mydas) and Olive Ridley Turtle (Lepidochelys olivacea) are the only sea turtles with recorded landings in the Pulau Pinang coastal area. The Green Turtle has been the most abundant and widely distributed sea turtle in this area since it was first surveyed in 1995. Statistical analysis by the Pulau Pinang Department of Fisheries on the distribution of sea turtles from 2001 through 2009 has identified Pantai Kerachut and Telok Kampi as the most strongly preferred beaches for Green Turtle landings, with records for almost every month in every year. Green Turtle tracks and nests have also been found along the coast of Pulau Pinang at Batu Ferringhi, Tanjong Bungah, Pantai Medan, Pantai Belanda, Telok Kumbar, Gertak Sanggul, Moonlight Beach, Telok Duyung, Telok Aling, Telok Bahang and Telok Katapang. The Olive Ridley Turtle is present in smaller numbers; landing and nesting have only been recorded on a few beaches. There are no previous records of Olive Ridley landings at Pantai Kerachut and Telok Kampi, but tracks and nests have been found at Telok Kumbar, Tanjong Bungah, Pantai Medan, Telok Duyung and Gertak Sanggul. A Turtle Conservation Centre has been established at Pantai Kerachut to protect these species from extinction in Pulau Pinang. This paper presents details of the records and distribution of sea turtles in Pulau Pinang from 1995 through 2009.

  5. The sea-finding behavior of hatchling olive ridley sea turtles, Lepidochelys olivacea, at the beach of San Miguel (Costa Rica)

    NASA Astrophysics Data System (ADS)

    Stapput, Katrin; Wiltschko, Wolfgang

    2005-05-01

    Newly hatched olive ridley sea turtles (Lepidochelys olivacea) were tested for their directional preferences in a sand-filled circular arena in total darkness. Hatchlings that had crawled about 5 m on the beach, toward the sea preferred the southwesterly direction that would have brought them to the water line, whereas hatchlings that had been denied this experience headed eastward, a direction of unclear origin. These data suggest that a short crawl across the natural beach can set the direction in which the young turtles subsequently move. The crawling experience was sufficient to acquire the compass course that they later follow, probably with the help of a magnetic compass, not only in the water, but already while still on land.

  6. The sea-finding behavior of hatchling olive ridley sea turtles, Lepidochelys olivacea, at the beach of San Miguel (Costa Rica).

    PubMed

    Stapput, Katrin; Wiltschko, Wolfgang

    2005-05-01

    Newly hatched olive ridley sea turtles (Lepidochelys olivacea) were tested for their directional preferences in a sand-filled circular arena in total darkness. Hatchlings that had crawled about 5 m on the beach, toward the sea preferred the southwesterly direction that would have brought them to the water line, whereas hatchlings that had been denied this experience headed eastward, a direction of unclear origin. These data suggest that a short crawl across the natural beach can set the direction in which the young turtles subsequently move. The crawling experience was sufficient to acquire the compass course that they later follow, probably with the help of a magnetic compass, not only in the water, but already while still on land.

  7. The characterization of cytosolic glutathione transferase from four species of sea turtles: loggerhead (Caretta caretta), green (Chelonia mydas), olive ridley (Lepidochelys olivacea), and hawksbill (Eretmochelys imbricata).

    PubMed

    Richardson, Kristine L; Gold-Bouchot, Gerardo; Schlenk, Daniel

    2009-08-01

    Glutathione s-transferases (GST) play a critical role in the detoxification of exogenous and endogenous electrophiles, as well as the products of oxidative stress. As compared to mammals, GST activity has not been extensively characterized in reptiles. Throughout the globe, most sea turtle populations face the risk of extinction. Of the natural and anthropogenic threats to sea turtles, the effects of environmental chemicals and related biochemical mechanisms, such as GST catalyzed detoxification, are probably the least understood. In the present study, GST activity was characterized in four species of sea turtles with varied life histories and feeding strategies: loggerhead (Caretta caretta), green (Chelonia mydas), olive ridley (Lepidochelys olivacea), and hawksbill (Eretmochelys imbricata). Although similar GST kinetics was observed between species, rates of catalytic activities using class-specific substrates show inter- and intra-species variation. GST from the spongivorous hawksbill sea turtle shows 3-4.5 fold higher activity with the substrate 4-nitrobenzylchloride than the other 3 species. GST from the herbivorous green sea turtle shows 3 fold higher activity with the substrate ethacrynic acid than the carnivorous olive ridley sea turtle. The results of this study may provide insight into differences in biotransformation potential in the four species of sea turtles and the possible health impacts of contaminant biotransformation by sea turtles.

  8. Basal and stress-induced corticosterone levels in olive ridley sea turtles (Lepidochelys olivacea) in relation to their mass nesting behavior.

    PubMed

    Valverde, R A; Owens, D W; MacKenzie, D S; Amoss, M S

    1999-11-01

    Adrenocortical responsiveness to turning stress was examined in wild, reproductively-active olive ridley sea turtles (Lepidochelys olivacea) in relation to their mass nesting (arribada) behavior. We hypothesized that the high sensitivity threshold (HST) observed in ovipositing sea turtles is associated with a diminished sensitivity of the hypothalamo-pituitary-adrenal (HPA) axis to stressful stimuli in arribada females. We tested this hypothesis by determining whether arribada females exhibited an increased activation threshold of the HPA axis to an imposed stressor (turning stress). Mean basal corticosterone (B) and glucose levels were below 1.0 ng/ml and 60 mg/dl, respectively. Basal B remained unchanged throughout a 24-hr period in basking females. Most animals responded to turning stress with elevated mean B levels (up to 6.5 ng/ml after 6 hr) and no increase in circulating glucose. Nearly 50% of females (and none of the males) were refractory to the stimulation. Males exhibited the most rapid response, with B levels significantly elevated by 20 min over basal levels. Among females, arribada and solitary nesters exhibited a slower rate of response than basking, non-nesting animals. These results demonstrate that olive ridleys exhibit stress-induced changes in circulating B which are slower than those observed in most reptilian and in mammalian, avian, and piscine species. Furthermore, the presence of refractory females and the relatively slower increase in B in arribada and solitary nesters indicate a hyporesponsiveness of the HPA axis to turning stress in nesting olive ridleys. The hyporesponsiveness may be part of a mechanism to facilitate arribada nesting. J. Exp. Zool. 284:652-662, 1999.

  9. 76 FR 4635 - Endangered Species; File No. 15552

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-26

    ...), loggerhead (Caretta caretta), Kemp's ridley (Lepidochelys kempii), olive ridley (Lepidochelys olivacea..., loggerhead, hawksbill, leatherback, Kemp's ridley, olive ridley, and unidentified hardshell sea turtles by... 120 olive ridley/ unknown hardshell sea turtles would be handled, identified, photographed,...

  10. 76 FR 45781 - Endangered Species; File No. 15552

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-01

    ...), Kemp's ridley (Lepidochelys kempii), olive ridley (Lepidochelys olivacea), leatherback (Dermochelys... a scientific research permit to take green, loggerhead, hawksbill, leatherback, Kemp's ridley, olive... monitor the take of green, loggerhead, hawksbill, leatherback, Kemp's ridley, olive ridley,...

  11. Expression of aromatase in the embryonic brain of the olive ridley sea turtle (Lepidochelys olivacea), and the effect of bisphenol-A in sexually differentiated embryos.

    PubMed

    Gómez-Picos, Patsy; Sifuentes-Romero, Itzel; Merchant-Larios, Horacio; Hernández-Cornejo, Rubí; Díaz-Hernández, Verónica; García-Gasca, Alejandra

    2014-01-01

    Brain aromatase participates in several biological processes, such as regulation of the reproductive-endocrine axis, memory, stress, sexual differentiation of the nervous system, male sexual behavior, and brain repair. Here we report the isolation and expression of brain aromatase in olive ridley sea turtle (Lepidochelys olivacea) embryos incubated at male- and female-promoting temperatures (MPT and FPT, respectively), at the thermosensitive period (TSP) and the sex-differentiated period. Also, aromatase expression was assessed in differentiated embryos exposed to bisphenol-A (BPA) during the TSP. BPA is a monomer of polycarbonate plastics and is considered an endocrine-disrupting compound. Normal aromatase expression was measured in both forebrain and hindbrain, showing higher expression levels in the forebrain of differentiated embryos at both incubation temperatures. Although no significant differences were detected in the hindbrain, expression was slightly higher at MPT. BPA did not affect aromatase expression neither in forebrains or hindbrains from embryos incubated at MPT, whereas at FPT an inverted U-shape curve was observed in forebrains with significant differences at lower concentrations, whereas in hindbrains a non-significant increment was observed at higher concentrations. Our data indicate that both incubation temperature and developmental stage are critical factors affecting aromatase expression in the forebrain. Because of the timing and location of aromatase expression in the brain, we suggest that brain aromatase may participate in the imprinting of sexual trends related to reproduction and sexual behavior at the onset of sex differentiation, and BPA exposure may impair aromatase function in the female forebrain.

  12. [Chemical composition of eggs of the Olive Ridley Lepidochelys olivacea (Testudines: Cheloniidae) and it's potential as a food source].

    PubMed

    Castro-González, María Isabel; Pérez-Gil Romo, Fernando

    2011-12-01

    The Olive Ridley is a worldwide distributed species with high nesting production per season, and in La Escobilla Oaxaca, México, there is a 70% of non-hatched eggs that are lost. In order to evaluate their potential use as a source for human and animal food products, their chemical composition was analyzed. Lyophilized egg samples from 25 turtles were obtained and were analyzed following the analytical methods for fatty acids, protein, fat, ash, moisture, amino acids, vitamins, cholesterol and microbiological agents. The analytical composition obtained was (g/100g): moisture (4.7), ash (3.8), protein (53.7), and fat (47.4). The essential amino acid (g aa/100g protein) content was: Ile (4.4), Lys (6.6), Leu (7.4), Met+Cys (8.8), Phe+Tyr (10.8). The vitamin content was: retinol (340 microg/100g), cholecalciferol (5.91 microg/100g) and 8.6 mg/100 tocopherol, 0.3 mg/100g thiamine and 1.1 mg/100g riboflavin. The total lipid content (TL), fatty acids (FA), and cholesterol (Chol) were divided into three groups based on the weight of the turtle: (TL) (44.3-48.7-49.1g/100g) and (Chol) (518.4-522.5 mg/100g-728.7). A total of 17 Saturated FA (SFA), 8 Monounsaturated FA (MUFA) and 11 Polyunsaturated FA (PUFA) were identified. The most abundant SFA (mg/100g) were: C14:0 (445-772), C16:0 (485-1263); MUFA: C16:1 (456-716), C18:1n-9c (904-1754), and PUFA: C20:4n-6 (105-217); two n-3 fatty acids were identified EPA (48-103) and DHA (97-189).There were significant differences (Fisher, p < 0.05) for: (Chol), total FA, SFA, MUFA, PUFAs and n-3 (EPA + DHA) FA. It was not detected any microbiological agent. In conclusion, lyophilized L. olivacea eggs are an option for its inclusion in the development of food products as they can be used as a high quality biological protein and n-3 fatty acid source for fortification and enrichment.

  13. Predicting the distribution of oceanic-stage Kemp's ridley sea turtles

    PubMed Central

    Putman, Nathan F.; Mansfield, Katherine L.; He, Ruoying; Shaver, Donna J.; Verley, Philippe

    2013-01-01

    The inaccessibility of open ocean habitat and the cryptic nature of small animals are fundamental problems when assessing the distribution of oceanic-stage sea turtles and other marine animals sharing similar life-history traits. Most methods that estimate patterns of abundance cannot be applied in situations that are extremely data limited. Here, we use a movement ecology framework to generate the first predicted distributions for the oceanic stage of the Kemp's ridley sea turtle (Lepidochelys kempii). Our simulations of particle dispersal within ocean circulation models reveal substantial annual variation in distribution and survival among simulated cohorts. Such techniques can help prioritize areas for conservation, and supply inputs for more realistic demographic models attempting to characterize population trends. PMID:23945206

  14. Is the geographic distribution of nesting in the Kemp's ridley turtle shaped by the migratory needs of offspring?

    PubMed

    Putman, Nathan F; Shay, Thomas J; Lohmann, Kenneth J

    2010-09-01

    Across the geographic area that a species uses for reproduction, the density of breeding individuals is typically highest in locations where ecological factors promote reproductive success. For migratory animals, fitness depends, in part, on producing offspring that migrate successfully to habitats suitable for the next life-history stage. Thus, natural selection might favor reproduction in locations with conditions that facilitate the migration of offspring. To investigate this concept, we studied the Kemp's ridley sea turtle (Lepidochelys kempii) to determine whether coastal areas with the highest levels of nesting have particularly favorable conditions for hatchling migration. We modeled the passive drift of young Kemp's ridley turtles from seven nesting regions within the Gulf of Mexico to foraging grounds using the particle-tracking program ICHTHYOP and surface-current output from HYCOM (HYbrid Coordinate Ocean Model). Results revealed that geographic regions with conditions that facilitate successful migration to foraging grounds typically have higher abundance of nests than do regions where oceanographic conditions are less favorable and successful migration is difficult for hatchlings. Thus, our findings are consistent with the hypothesis that, for the Kemp's ridley turtle and perhaps for other migrants, patterns of abundance across the breeding range are shaped in part by conditions that promote or impede the successful migration of offspring.

  15. The Impact of Turtle Excluder Devices and Fisheries Closures on Loggerhead and Kemp's Ridley Strandings in the Western Gulf of Mexico

    USGS Publications Warehouse

    Lewison, R.L.; Crowder, L.B.; Shaver, D.J.

    2003-01-01

    The Sea Turtle Stranding and Salvage Network has been monitoring turtle strandings for more than 20 years in the United States. High numbers of strandings in the early to mid-1980s prompted regulations to require turtle excluder devices (TEDs) on shrimping vessels (trawlers). Following year-round TED implementation in 1991, however, stranding levels in the Gulf of Mexico increased. We evaluated the efficacy of TEDs and other management actions (e.g., fisheries closures) on loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) turtle populations by analyzing a long-term, stranding data set from the western Gulf of Mexico. Our analyses suggest that both sea turtle population growth and shrimping activity have contributed to the observed increase in strandings. Compliance with regulations requiring turtle excluder devices was a significant factor in accounting for annual stranding variability: low compliance was correlated with high levels of strandings. Our projections suggest that improved compliance with TED regulations will reduce strandings to levels that, in conjunction with other protective measures, should promote population recoveries for loggerhead and Kemp's ridley turtles. Local, seasonal fisheries closures, concurrent with TED enforcement, could reduce strandings to even lower levels. A seasonal closure adjacent to a recently established Kemp's ridley nesting beach may also reduce mortality of nesting adults and thus promote long-term population persistence by fostering the establishment of a robust secondary nesting site.

  16. Foraging area fidelity for Kemp's ridleys in the Gulf of Mexico

    USGS Publications Warehouse

    Shaver, Donna J.; Hart, Kristen M.; Fujisaki, Ikuko; Rubio, Cynthia; Sartain-Iverson, Autumn R.; Peña, Jaime; Burchfield, Patrick M.; Gamez, Daniel Gomez; Ortiz, Jaime

    2013-01-01

    For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998–2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their "final" foraging sites. We identified new foraging "hotspots" where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water <68 m deep and a mean distance of 33.2 km (±25.3 SD) from the nearest mainland coast. Distance to release site, distance to mainland shore, annual mean sea surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13-year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at-sea foraging habitats for this imperiled species.

  17. Foraging area fidelity for Kemp's ridleys in the Gulf of Mexico

    PubMed Central

    Shaver, Donna J; Hart, Kristen M; Fujisaki, Ikuko; Rubio, Cynthia; Sartain, Autumn R; Peña, Jaime; Burchfield, Patrick M; Gamez, Daniel Gomez; Ortiz, Jaime

    2013-01-01

    For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998–2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their “final” foraging sites. We identified new foraging “hotspots” where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water <68 m deep and a mean distance of 33.2 km (±25.3 SD) from the nearest mainland coast. Distance to release site, distance to mainland shore, annual mean sea surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13-year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at-sea foraging habitats for this imperiled species. PMID:23919146

  18. Foraging area fidelity for Kemp's ridleys in the Gulf of Mexico.

    PubMed

    Shaver, Donna J; Hart, Kristen M; Fujisaki, Ikuko; Rubio, Cynthia; Sartain, Autumn R; Peña, Jaime; Burchfield, Patrick M; Gamez, Daniel Gomez; Ortiz, Jaime

    2013-07-01

    For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998-2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their "final" foraging sites. We identified new foraging "hotspots" where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water <68 m deep and a mean distance of 33.2 km (±25.3 SD) from the nearest mainland coast. Distance to release site, distance to mainland shore, annual mean sea surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13-year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at-sea foraging habitats for this imperiled species.

  19. Variability in age and size at maturation, reproductive longevity, and long-term growth dynamics for Kemp's ridley sea turtles in the Gulf of Mexico

    PubMed Central

    Goshe, Lisa R.; Coggins, Lewis; Shaver, Donna J.; Higgins, Ben; Landry, Andre M.; Bailey, Rhonda

    2017-01-01

    Effective management of protected sea turtle populations requires knowledge not only of mean values for demographic and life-history parameters, but also temporal and spatial trends, variability, and underlying causes. For endangered Kemp’s ridley sea turtles (Lepidochelys kempii), the need for baseline information of this type has been emphasized during attempts to understand causes underlying the recent truncation in the recovery trajectory for nesting females. To provide insight into variability in age and size at sexual maturation (ASM and SSM) and long-term growth patterns likely to influence population trends, we conducted skeletochronological analysis of humerus bones from 333 Kemp’s ridleys stranded throughout the Gulf of Mexico (GOM) from 1993 to 2010. Ranges of possible ASMs (6.8 to 21.8 yr) and SSMs (53.3 to 68.3 cm straightline carapace length (SCL)) estimated using the “rapprochement” skeletal growth mark associated with maturation were broad, supporting incorporation of a maturation schedule in Kemp’s ridley population models. Mean ASMs estimated from rapprochement and by fitting logistic, generalized additive mixed, and von Bertalanffy growth models to age and growth data ranged from 11 to 13 yr; confidence intervals for the logistic model predicted maturation of 95% of the population between 11.9 and 14.8 yr. Early juvenile somatic growth rates in the GOM were greater than those previously reported for the Atlantic, indicating potential for differences in maturation trajectories between regions. Finally, long-term, significant decreases in somatic growth response were found for both juveniles and adults, which could influence recruitment to the reproductive population and observed nesting population trends. PMID:28333937

  20. Variability in age and size at maturation, reproductive longevity, and long-term growth dynamics for Kemp's ridley sea turtles in the Gulf of Mexico.

    PubMed

    Avens, Larisa; Goshe, Lisa R; Coggins, Lewis; Shaver, Donna J; Higgins, Ben; Landry, Andre M; Bailey, Rhonda

    2017-01-01

    Effective management of protected sea turtle populations requires knowledge not only of mean values for demographic and life-history parameters, but also temporal and spatial trends, variability, and underlying causes. For endangered Kemp's ridley sea turtles (Lepidochelys kempii), the need for baseline information of this type has been emphasized during attempts to understand causes underlying the recent truncation in the recovery trajectory for nesting females. To provide insight into variability in age and size at sexual maturation (ASM and SSM) and long-term growth patterns likely to influence population trends, we conducted skeletochronological analysis of humerus bones from 333 Kemp's ridleys stranded throughout the Gulf of Mexico (GOM) from 1993 to 2010. Ranges of possible ASMs (6.8 to 21.8 yr) and SSMs (53.3 to 68.3 cm straightline carapace length (SCL)) estimated using the "rapprochement" skeletal growth mark associated with maturation were broad, supporting incorporation of a maturation schedule in Kemp's ridley population models. Mean ASMs estimated from rapprochement and by fitting logistic, generalized additive mixed, and von Bertalanffy growth models to age and growth data ranged from 11 to 13 yr; confidence intervals for the logistic model predicted maturation of 95% of the population between 11.9 and 14.8 yr. Early juvenile somatic growth rates in the GOM were greater than those previously reported for the Atlantic, indicating potential for differences in maturation trajectories between regions. Finally, long-term, significant decreases in somatic growth response were found for both juveniles and adults, which could influence recruitment to the reproductive population and observed nesting population trends.

  1. Inter-nesting movements and habitat-use of adult female Kemp's ridley turtles in the Gulf of Mexico.

    PubMed

    Shaver, Donna J; Hart, Kristen M; Fujisaki, Ikuko; Bucklin, David; Iverson, Autumn R; Rubio, Cynthia; Backof, Thomas F; Burchfield, Patrick M; de Jesus Gonzales Diaz Miron, Raul; Dutton, Peter H; Frey, Amy; Peña, Jaime; Gomez Gamez, Daniel; Martinez, Hector J; Ortiz, Jaime

    2017-01-01

    Species vulnerability is increased when individuals congregate in restricted areas for breeding; yet, breeding habitats are not well defined for many marine species. Identification and quantification of these breeding habitats are essential to effective conservation. Satellite telemetry and switching state-space modeling (SSM) were used to define inter-nesting habitat of endangered Kemp's ridley turtles (Lepidochelys kempii) in the Gulf of Mexico. Turtles were outfitted with satellite transmitters after nesting at Padre Island National Seashore, Texas, USA, from 1998 through 2013 (n = 60); Rancho Nuevo, Tamaulipas, Mexico, during 2010 and 2011 (n = 11); and Tecolutla, Veracruz, Mexico, during 2012 and 2013 (n = 11). These sites span the range of nearly all nesting by this species. Inter-nesting habitat lies in a narrow band of nearshore western Gulf of Mexico waters in the USA and Mexico, with mean water depth of 14 to 19 m within a mean distance to shore of 6 to 11 km as estimated by 50% kernel density estimate, α-Hull, and minimum convex polygon methodologies. Turtles tracked during the inter-nesting period moved, on average, 17.5 km/day and a mean total distance of 398 km. Mean home ranges occupied were 725 to 2948 km2. Our results indicate that these nearshore western Gulf waters represent critical inter-nesting habitat for this species, where threats such as shrimp trawling and oil and gas platforms also occur. Up to half of all adult female Kemp's ridleys occupy this habitat for weeks to months during each nesting season. Because inter-nesting habitat for this species is concentrated in nearshore waters of the western Gulf of Mexico in both Mexico and the USA, international collaboration is needed to protect this essential habitat and the turtles occurring within it.

  2. Migratory corridors of adult female Kemp’s ridley turtles in the Gulf of Mexico

    USGS Publications Warehouse

    Shaver, Donna J.; Hart, Kristen M.; Fujisaki, Ikuko; Rubio, Cynthia; Sartain-Iverson, Autumn R.; Pena, Jaime; Gamez, Daniel Gomez; Gonzales Diaz Miron, Raul de Jesus; Burchfield, Patrick M.; Martinez, Hector J.; Ortiz, Jaime

    2016-01-01

    For many marine species, locations of migratory pathways are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to define the migratory corridor used by Kemp's ridley turtles (Lepidochelys kempii) in the Gulf of Mexico. The turtles were tagged after nesting at Padre Island National Seashore, Texas, USA from 1997 to 2014 (PAIS; n = 80); Rancho Nuevo, Tamaulipas, Mexico from 2010 to 2011 (RN; n = 14); Tecolutla, Veracruz, Mexico from 2012 to 2013 (VC; n = 13); and Gulf Shores, Alabama, USA during 2012 (GS; n = 1). The migratory corridor lies in nearshore Gulf of Mexico waters in the USA and Mexico with mean water depth of 26 m and a mean distance of 20 km from the nearest mainland coast. Migration from the nesting beach is a short phenomenon that occurs from late-May through August, with a peak in June. There was spatial similarity of post-nesting migratory pathways for different turtles over a 16 year period. Thus, our results indicate that these nearshore Gulf waters represent a critical migratory habitat for this species. However, there is a gap in our understanding of the migratory pathways used by this and other species to return from foraging grounds to nesting beaches. Therefore, our results highlight the need for tracking reproductive individuals from foraging grounds to nesting beaches. Continued tracking of adult females from PAIS, RN, and VC nesting beaches will allow further study of environmental and bathymetric components of migratory habitat and threats occurring within our defined corridor. Furthermore, the existence of this migratory corridor in nearshore waters of both the USA and Mexico demonstrates that international cooperation is necessary to protect essential migratory habitat for this imperiled species.

  3. Inter-nesting movements and habitat-use of adult female Kemp’s ridley turtles in the Gulf of Mexico

    PubMed Central

    Hart, Kristen M.; Fujisaki, Ikuko; Bucklin, David; Iverson, Autumn R.; Rubio, Cynthia; Backof, Thomas F.; Burchfield, Patrick M.; de Jesus Gonzales Diaz Miron, Raul; Dutton, Peter H.; Frey, Amy; Peña, Jaime; Gomez Gamez, Daniel; Martinez, Hector J.; Ortiz, Jaime

    2017-01-01

    Species vulnerability is increased when individuals congregate in restricted areas for breeding; yet, breeding habitats are not well defined for many marine species. Identification and quantification of these breeding habitats are essential to effective conservation. Satellite telemetry and switching state-space modeling (SSM) were used to define inter-nesting habitat of endangered Kemp’s ridley turtles (Lepidochelys kempii) in the Gulf of Mexico. Turtles were outfitted with satellite transmitters after nesting at Padre Island National Seashore, Texas, USA, from 1998 through 2013 (n = 60); Rancho Nuevo, Tamaulipas, Mexico, during 2010 and 2011 (n = 11); and Tecolutla, Veracruz, Mexico, during 2012 and 2013 (n = 11). These sites span the range of nearly all nesting by this species. Inter-nesting habitat lies in a narrow band of nearshore western Gulf of Mexico waters in the USA and Mexico, with mean water depth of 14 to 19 m within a mean distance to shore of 6 to 11 km as estimated by 50% kernel density estimate, α-Hull, and minimum convex polygon methodologies. Turtles tracked during the inter-nesting period moved, on average, 17.5 km/day and a mean total distance of 398 km. Mean home ranges occupied were 725 to 2948 km2. Our results indicate that these nearshore western Gulf waters represent critical inter-nesting habitat for this species, where threats such as shrimp trawling and oil and gas platforms also occur. Up to half of all adult female Kemp’s ridleys occupy this habitat for weeks to months during each nesting season. Because inter-nesting habitat for this species is concentrated in nearshore waters of the western Gulf of Mexico in both Mexico and the USA, international collaboration is needed to protect this essential habitat and the turtles occurring within it. PMID:28319178

  4. 78 FR 26323 - Endangered Species; File No. 17183

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-06

    ...), hawksbill (Eretmochelys imbricata), and Kemp's ridley (Lepidochelys kempii) sea turtles for purposes of... ridley sea turtles had been submitted by the above-named individual. The requested permit has been issued... on the demographics and movements of green, loggerhead, hawksbill, and Kemp's ridley sea turtles...

  5. [Cloacal and nasal bacterial flora of Lepidochelys olivacea (Testudines: Cheloniidae) from the North Pacific Coast of Costa Rica].

    PubMed

    Santoro, Mario; Orrego, Carlos Mario; Hernández Gómez, Giovanna

    2006-03-01

    Cloacal and nasal bacterial flora of Lepidochelys olivacea (Testudines: Cheloniidae) from the North Pacific coast of Costa Rica. The aerobic cloacal and nasal bacterial flora of 45 apparently healthy female olive ridley sea turtles (Lepidochelys olivacea) was studied at Nancite nesting beach, in Santa Rosa National Park (Costa Rican North Pacific) during July and August 2002. Bacterial samples were obtained by inserting sterile swabs directly into the cloaca and the nasal cavities of the turtles. Ninety-nine aerobic bacterial isolates, including 10 Gram-negative and 5 Gram-positive bacteria, were recovered. The most common bacteria cultured were Aeromonas spp. (13/45) and Citrobacter freundi (6/45) from cloacal samples and Bacillus spp. (32/45), Staphylococcus aureus (6/45) and Corynebacterium spp. (5/45) from nasal ducts. The results of the present study showed that the aerobic bacterial flora of nesting female olive ridleys was composed of several potential human and animal microbe pathogens.

  6. The panmixia paradigm of eastern Pacific olive ridley turtles revised: consequences for their conservation and evolutionary biology.

    PubMed

    López-Castro, M C; Rocha-Olivares, A

    2005-10-01

    Previous studies of the olive ridley Lepidochelys olivacea population structure in the tropical eastern Pacific have indicated the existence of a single panmictic population ranging from Costa Rica to Mexico. This information has been used to design specific management measures to conserve primary nesting beaches in Mexico. However, little is known about olive ridleys in the Baja California Peninsula, their northernmost reproductive limit, where recent observations have shown differences in nesting female behaviour and size of hatchlings relative to other continental rookeries. We used mtDNA control region sequences from 137 turtles from five continental and four peninsular nesting sites to determine whether such differences correspond to a genetic distinction of Baja California olive ridleys or to phenotypic plasticity associated with the extreme environmental nesting conditions of this region. We found that genetic diversity in peninsular turtles was significantly lower than in continental nesting colonies. Analysis of molecular variance revealed a significant population structure (Phi ST = 0.048, P = 0.006) with the inclusion of peninsular samples. Our results: (i) suggest that the observed phenotypic variation may be associated with genetic differentiation and reproductive isolation; (ii) support the recent colonization of the eastern Pacific by Lepidochelys; (iii) reveal genetic signatures of historical expansion and colonization events; and (iv) significantly challenge the notion of a single genetic and conservation unit of olive ridleys in the eastern Pacific. We conclude that conservation measures for olive ridleys in Mexico should be revised to grant peninsular beaches special attention.

  7. Overlapping genetic codes for overlapping frameshifted genes in Testudines, and Lepidochelys olivacea as special case.

    PubMed

    Seligmann, Hervé

    2012-12-01

    Mitochondrial genes code for additional proteins after +2 frameshifts by reassigning stops to code for amino acids, which defines overlapping genetic codes for overlapping genes. Turtles recode stops UAR → Trp and AGR → Lys (AGR → Gly in the marine Olive Ridley turtle, Lepidochelys olivacea). In Lepidochelys the +2 frameshifted mitochondrial Cytb gene lacks stops, open reading frames from other genes code for unknown proteins, and for regular mitochondrial proteins after frameshifts according to the overlapping genetic code. Lepidochelys' inversion between proteins coded by regular and overlapping genetic codes substantiates the existence of overlap coding. ND4 differs among Lepidochelys mitochondrial genomes: it is regular in DQ486893; in NC_011516, the open reading frame codes for another protein, the regular ND4 protein is coded by the frameshifted sequence reassigning stops as in other turtles. These systematic patterns are incompatible with Genbank/sequencing errors and DNA decay. Random mixing of synonymous codons, conserving main frame coding properties, shows optimization of natural sequences for overlap coding; Ka/Ks analyses show high positive (directional) selection on overlapping genes. Tests based on circular genetic codes confirm programmed frameshifts in ND3 and ND4l genes, and predicted frameshift sites for overlap coding in Lepidochelys. Chelonian mitochondria adapt for overlapping gene expression: cloverleaf formation by antisense tRNAs with predicted anticodons matching stops coevolves with overlap coding; antisense tRNAs with predicted expanded anticodons (frameshift suppressor tRNAs) associate with frameshift-coding in ND3 and ND4l, a potential regulation of frameshifted overlap coding. Anaeroby perhaps switched between regular and overlap coding genes in Lepidochelys.

  8. 76 FR 20324 - Endangered Species; File No. 15606

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ... grass habitats off of Texas; (2) determine trends in seasonal abundance and movement of green, Kemp's... permit to take green (Chelonia mydas), Kemp's ridley (Lepidochelys kempii), loggerhead (Caretta caretta... for a scientific research permit to take green, Kemp's ] ridley, loggerhead, and hawksbill sea...

  9. Waste characterization study for the Kemp's Ridley sea turtle. Technical memo

    SciTech Connect

    Malone, R.F.; Guarisco, M.

    1988-02-01

    The Kemp's Ridley sea turtle, Lepidochelys kempi, is an endangered species. The National Marine Fisheries Service's Head Start program is part of an international operation to save the turtles from extinction. Under the Head Start program, eggs from the Ridley's only known wild nesting beach at Rancho Nuevo in Mexico are transported to Padre Island on the Texas coast to be hatched. The head start enables the turtles to develop a survival advantage. The principal objective was to develop baseline waste-characterization data required to design a waste-water treatment scheme for the Galveston Head Start facility. As a secondary objective, preliminary testing of some filtration components was undertaken to determine which units were most appropriate for inclusion in a wastewater treatment scheme.

  10. Trace elements in blood of sea turtles Lepidochelys olivacea in the Gulf of California, Mexico.

    PubMed

    Zavala-Norzagaray, A A; Ley-Quiñónez, C P; Espinosa-Carreón, T L; Canizalez-Román, A; Hart, C E; Aguirre, A A

    2014-11-01

    This study determined the concentrations of heavy metals in blood collected from Pacific Ridley sea turtles (Lepidochelys olivacea) inhabiting the coast of Guasave, Mexico, in the Gulf of California. The highest reported metal concentration in blood was Zn, followed by Se. Of nonessential toxic metals, As was reported in higher percentage compared to Cd. The concentrations of metals detected were present as follows: Zn > Se > Mn > As > Ni > Cd > Cu. Cd concentration in blood is higher in our population in comparison with other populations of L. olivacea, and even higher in other species of sea turtles. Our study reinforces the usefulness of blood for the monitoring of the levels of contaminating elements, and is easily accessible and nonlethal for sea turtles.

  11. 75 FR 16428 - Endangered Species; File Nos. 15112 and 13307-02

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ... ridley (Lepidochelys kempii), green (Chelonia mydas), and hawksbill (Eretmochelys imbricata) sea turtles... modification to scientific research Permit No. 13307-01 to take green sea turtles. DATES: Written, telefaxed... composition of populations of sea turtles found in the commercial fishing areas of the Northwest...

  12. 78 FR 13642 - Endangered Species; File No. 17506

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-28

    ...), Kemp's ridley (Lepidochelys kempii), and leatherback (Dermochelys coriaceae) sea turtles for purposes... permit to continue to characterize the population of sea turtles that utilize the nearshore hard bottom reefs in Brevard County, FL. Up to 50 green and six loggerhead sea turtles would be tangle netted,...

  13. 76 FR 23571 - Marine Mammals and Endangered Species; File Nos. 15415 and 14622

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-27

    ... given that NMFS has issued two permits to conduct research on marine mammals or sea turtles. See...), Kemp's ridley (Lepidochelys ] kempii), and loggerhead (Caretta caretta) sea turtles had been submitted... 32218, was issued a five-year permit to: (1) Monitor the abundance of loggerhead and green sea...

  14. Levels of perfluorinated acids (PFCAs) in different tissues of Lepidochelys olivacea sea turtles from the Escobilla beach (Oaxaca, Mexico).

    PubMed

    Pasanisi, Eugenia; Cortés-Gómez, Adriana A; Pérez-López, Marcos; Soler, Francisco; Hernández-Moreno, David; Guerranti, Cristiana; Martellini, Tania; Fuentes-Mascorro, Gisela; Romero, Diego; Cincinelli, Alessandra

    2016-12-01

    Lepidochelys olivacea is the most abundant and globally distributed sea turtle species in the world and thus, monitoring this species for persistent organic pollutants, such as perfluorinated chemicals, is fundamental for their protection. This study was the first to evaluate the occurrence of five PFCAs (PFOA, PFNA, PFDA, PFUnA, PFDoA) in liver and blood samples of Olive Ridley turtle population from the Escobilla beach (Oaxaca, Mexico). PFDA and PFUnA were the predominant PFCs in blood samples (detected in 93% and 84% of samples, respectively) and were also present in the highest concentrations. Liver samples showed higher PFCA concentrations than whole blood samples, with PFNA and PFDA the most abundant PFCs congeners in liver samples, detected in 65% and 47% of the samples, respectively. The measured levels of contaminants in the blood samples of Lepidochelys olivacea sea turtles were compared to the levels reported in the literature for other turtle species. While linear significant correlations between PFNA, PFDA and PFUnA concentrations in blood samples and curved carapace lengths were determined, no correlation was found for PFOA, supporting the hypothesis that sea turtles could have a higher ability to eliminate this perfluorinated chemical from their blood than other PFCAs. However, we do not know if the concentrations are species or sampling areas dependent.

  15. Sir Harold Ridley: innovator of cataract surgery.

    PubMed

    Sarwar, H; Modi, N

    2014-09-01

    Cataract surgery has evolved greatly over the years, from the ancient practice of 'couching' where the lens is dislodged, to the modern surgical techniques of today. Sir Harold Ridley's invention of the intraocular lens (IOL) has altered the approach towards cataract surgery, benefitting individuals worldwide. This has been his most notable contribution, it is therefore interesting to explore the build up to this event and gain an understanding of the issues faced by Sir Ridley. This paper explores the significant events and key developments that influenced one of the most valuable innovations in the context of cataract surgery--the intraocular lens.

  16. Using Satellite Tracking to Optimize Protection of Long-Lived Marine Species: Olive Ridley Sea Turtle Conservation in Central Africa

    PubMed Central

    Maxwell, Sara M.; Breed, Greg A.; Nickel, Barry A.; Makanga-Bahouna, Junior; Pemo-Makaya, Edgard; Parnell, Richard J.; Formia, Angela; Ngouessono, Solange; Godley, Brendan J.; Costa, Daniel P.; Witt, Matthew J.; Coyne, Michael S.

    2011-01-01

    Tractable conservation measures for long-lived species require the intersection between protection of biologically relevant life history stages and a socioeconomically feasible setting. To protect breeding adults, we require knowledge of animal movements, how movement relates to political boundaries, and our confidence in spatial analyses of movement. We used satellite tracking and a switching state-space model to determine the internesting movements of olive ridley sea turtles (Lepidochelys olivacea) (n = 18) in Central Africa during two breeding seasons (2007-08, 2008-09). These movements were analyzed in relation to current park boundaries and a proposed transboundary park between Gabon and the Republic of Congo, both created to reduce unintentional bycatch of sea turtles in marine fisheries. We additionally determined confidence intervals surrounding home range calculations. Turtles remained largely within a 30 km radius from the original nesting site before departing for distant foraging grounds. Only 44.6 percent of high-density areas were found within the current park but the proposed transboundary park would incorporate 97.6 percent of high-density areas. Though tagged individuals originated in Gabon, turtles were found in Congolese waters during greater than half of the internesting period (53.7 percent), highlighting the need for international cooperation and offering scientific support for a proposed transboundary park. This is the first comprehensive study on the internesting movements of solitary nesting olive ridley sea turtles, and it suggests the opportunity for tractable conservation measures for female nesting olive ridleys at this and other solitary nesting sites around the world. We draw from our results a framework for cost-effective protection of long-lived species using satellite telemetry as a primary tool. PMID:21589942

  17. Using satellite tracking to optimize protection of long-lived marine species: olive ridley sea turtle conservation in Central Africa.

    PubMed

    Maxwell, Sara M; Breed, Greg A; Nickel, Barry A; Makanga-Bahouna, Junior; Pemo-Makaya, Edgard; Parnell, Richard J; Formia, Angela; Ngouessono, Solange; Godley, Brendan J; Costa, Daniel P; Witt, Matthew J; Coyne, Michael S

    2011-05-11

    Tractable conservation measures for long-lived species require the intersection between protection of biologically relevant life history stages and a socioeconomically feasible setting. To protect breeding adults, we require knowledge of animal movements, how movement relates to political boundaries, and our confidence in spatial analyses of movement. We used satellite tracking and a switching state-space model to determine the internesting movements of olive ridley sea turtles (Lepidochelys olivacea) (n = 18) in Central Africa during two breeding seasons (2007-08, 2008-09). These movements were analyzed in relation to current park boundaries and a proposed transboundary park between Gabon and the Republic of Congo, both created to reduce unintentional bycatch of sea turtles in marine fisheries. We additionally determined confidence intervals surrounding home range calculations. Turtles remained largely within a 30 km radius from the original nesting site before departing for distant foraging grounds. Only 44.6 percent of high-density areas were found within the current park but the proposed transboundary park would incorporate 97.6 percent of high-density areas. Though tagged individuals originated in Gabon, turtles were found in Congolese waters during greater than half of the internesting period (53.7 percent), highlighting the need for international cooperation and offering scientific support for a proposed transboundary park. This is the first comprehensive study on the internesting movements of solitary nesting olive ridley sea turtles, and it suggests the opportunity for tractable conservation measures for female nesting olive ridleys at this and other solitary nesting sites around the world. We draw from our results a framework for cost-effective protection of long-lived species using satellite telemetry as a primary tool.

  18. 77 FR 61573 - Endangered and Threatened Species; Initiation of 5-Year Review for Kemp's Ridley, Olive Ridley...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-10

    ...; Initiation of 5-Year Review for Kemp's Ridley, Olive Ridley, Leatherback, and Hawksbill Sea Turtles AGENCY... (Dermochelys coriacea), and hawksbill (Eretmochelys imbricata) sea turtles under the Endangered Species Act of... sea turtles that has become available since that has become available since their last status...

  19. Correlation among thermosensitive period, estradiol response, and gonad differentiation in the sea turtle Lepidochelys olivacea.

    PubMed

    Merchant-Larios, H; Ruiz-Ramirez, S; Moreno-Mendoza, N; Marmolejo-Valencia, A

    1997-09-01

    Reptile embryos with temperature sex determination have a thermosensitive period (TSP). The finding that exogenous estradiol (E2) overcomes the effect of male-promoting temperature led to the idea that temperature may regulate estrogen concentration in the gonad during TSP. Since interspecific variations in TSP and in the effect of exogenous E2 exist, we undertook a study in the olive ridley Lepidochelys olivacea. Four parameters were correlated: the TSP (time dimension), the thermosensitive stages (rate of development), gonad development (histological aspect), and the estradiol response. Two kinds of experiments were performed: (1) Eggs were shifted once, at different stages of development, from a male-promoting temperature to a female-temperature (or vice versa) for the remainder of development. (2) Eggs at male-promoting temperature were treated once with 6 or 12 microg of estradiol (E2) at various times of incubation. Sex ratio was established around hatching in each experimental series. We found that the temporal dimension of the TSP was around 7 days (Days 20-27 of incubation) at a male-promoting or a female-promoting temperature. The rate of development of the whole embryo and gonadal growth was faster at female-promoting temperature than at male-promoting temperature. Formation of the genital ridge began at stage 21-22 and histological differentiation of the gonads occurred around stage 26-27. Although these stages coincided with the TSP, at male-promoting temperature the thermosensitive stages occurred earlier (from stages 20-21 to stages 23-24) than at female-promoting temperature (from stages 23-24 to stages 26-27). Thus, at male promoting-temperature, sex was determined in embryos with incipient or undifferentiated gonads. In contrast, E2 treatment continued to feminize the gonads of embryos at a male-promoting temperature beyond the TSP up to stage 25-26, but the E2-induced ovaries were significantly smaller than temperature-induced ovaries. It is

  20. Response of diencephalon but not the gonad to female-promoting temperature with elevated estradiol levels in the sea turtle Lepidochelys olivacea.

    PubMed

    Salame-Mendez, A; Herrera-Munoz, J; Moreno-Mendoza, N; Merchant-Larios, H

    1998-03-01

    Although temperature sex determination is well known in several reptile species, the physiological mechanism underlying this process remains to be elucidated. In the current work, we analyzed the levels of testosterone (T) and estradiol (E2) in the gonads; two brain regions--telencephalon (Te) and diencephalon/mesencephalon (Di)--and the serum of developing embryos of the olive ridley Lepidochelys olivacea incubated at male- or female-promoting temperatures. Conversion of pregnenolone (P5) to T and T to E2 were studied in the gonads and brain. The analyses were performed during three periods: the thermosensitive period (TSP), histologically undifferentiated gonads (UDG), and differentiated gonads (DG). In the gonads, serum, and brain, T concentrations were higher at the female-promoting temperature during the three periods, whereas in the gonads and serum, E2 levels were similar at the female and male-promoting temperature. In Di, the concentration of E2 was significantly higher at the female-promoting temperature. Biotransformation of P5 to T in gonadal tissues were slightly higher at the female-promoting temperature in TSP and increased during UDG and DG. Conversion of T to E2, however, was similar at the two temperatures during the three periods. In the brain, the Di showed a higher efficiency for transforming T to E2 at the female-promoting temperature. Our present results do not allow us to decide whether the diencephalon is the cause or the effect, but they conclusively demonstrate that, in L. olivacea, this region of the brain senses temperature during sex determination.

  1. Identification and evaluation of semiochemicals for the biological control of the beetle Omorgus suberosus (F.) (Coleoptera: Trogidae), a facultative predator of eggs of the sea turtle Lepidochelys olivacea (Eschscholtz).

    PubMed

    Cortez, Vieyle; Verdú, José R; Ortiz, Antonio J; Halffter, Gonzalo

    2017-01-01

    The beetle Omorgus suberosus (F.) is a facultative predator of eggs of the olive ridley turtle Lepidochelys olivacea (Eschscholtz). Laboratory and field investigations were conducted in order to characterize volatile attractants of O. suberosus and to explore the potential for application of these volatiles in a selective mass trapping method. Headspace sorptive extraction (HSSE) coupled to thermo-desorption gas chromatography-mass spectrometry (TD-GC-MS) analysis of the volatile constituents from beetles or turtle nests revealed 24 potential compounds. However, electroantennographic (EAG) measurements revealed antennal sensitivity only to indole, linoleic acid, trimethylamine, dimethyl sulphide, dimethyl disulphide and ammonia. Behavioural tests showed that these compounds are highly attractive to O. suberosus. Field trapping experiments revealed that indole and ammonia were more attractive than the other volatile compounds and showed similar attractiveness to that produced by conventional baits (chicken feathers). The use of a combined bait of indole and NH3 would therefore be the most effective trap design. The data presented are the first to demonstrate effective massive capture of O. suberosus using an attractant-based trapping method. These findings have potential for the development of an efficient mass trapping method for control of this beetle as part of efforts towards conservation of L. olivacea at La Escobilla in Oaxaca, Mexico.

  2. Identification and evaluation of semiochemicals for the biological control of the beetle Omorgus suberosus (F.) (Coleoptera: Trogidae), a facultative predator of eggs of the sea turtle Lepidochelys olivacea (Eschscholtz)

    PubMed Central

    Cortez, Vieyle; Ortiz, Antonio J.; Halffter, Gonzalo

    2017-01-01

    The beetle Omorgus suberosus (F.) is a facultative predator of eggs of the olive ridley turtle Lepidochelys olivacea (Eschscholtz). Laboratory and field investigations were conducted in order to characterize volatile attractants of O. suberosus and to explore the potential for application of these volatiles in a selective mass trapping method. Headspace sorptive extraction (HSSE) coupled to thermo-desorption gas chromatography–mass spectrometry (TD-GC-MS) analysis of the volatile constituents from beetles or turtle nests revealed 24 potential compounds. However, electroantennographic (EAG) measurements revealed antennal sensitivity only to indole, linoleic acid, trimethylamine, dimethyl sulphide, dimethyl disulphide and ammonia. Behavioural tests showed that these compounds are highly attractive to O. suberosus. Field trapping experiments revealed that indole and ammonia were more attractive than the other volatile compounds and showed similar attractiveness to that produced by conventional baits (chicken feathers). The use of a combined bait of indole and NH3 would therefore be the most effective trap design. The data presented are the first to demonstrate effective massive capture of O. suberosus using an attractant-based trapping method. These findings have potential for the development of an efficient mass trapping method for control of this beetle as part of efforts towards conservation of L. olivacea at La Escobilla in Oaxaca, Mexico. PMID:28192472

  3. Evaluation of hematology and serum biochemistry of cold-stunned green sea turtles (Chelonia mydas) in North Carolina, U.S.A.

    PubMed

    Anderson, Eric T; Harms, Craig A; Stringer, Elizabeth M; Cluse, Wendy M

    2011-06-01

    Hypothermia or cold-stunning is a condition in which the body temperature of an animal decreases below normal physiologic range and which has been linked to severe morbidity in sea turtles. Reports have focused on the physiologic changes caused by cold-stunning in Kemp's Ridley sea turtles (Lepidochelys kempii) and loggerhead sea turtles (Caretta caretta), but few have evaluated the green sea turtle (Chelonia mydas). This study evaluated hematologic and serum biochemical profiles of cold-stunned green sea turtles in North Carolina, USA. When compared with healthy, free-ranging juvenile green turtles from the same region, cold-stunned turtles exhibited hypoglycemia, hypocalcemia (both total and ionized calcium), hyponatremia, hypokalemia, hypoproteinemia, hypoalbuminemia, hyperphosphatemia, and elevations in uric acid and blood urea nitrogen. These findings contrast with some previously reported changes in cold-stunned Kemp's Ridley and loggerhead sea turtles. These results emphasize the importance of basing therapeutic regimens on biochemical analyses in cold-stunned sea turtles.

  4. 75 FR 12496 - Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ... Plans; Recovery Plan for the Kemp's Ridley Sea Turtle AGENCIES: National Marine Fisheries Service (NMFS... availability for public review of the draft Bi-National Recovery Plan (Plan) for the Kemp's Ridley Sea Turtle... turtles. The Plan identifies substantive actions needed to achieve recovery by addressing the threats...

  5. Fishery gear interactions from stranded bottlenose dolphins, Florida manatees and sea turtles in Florida, U.S.A.

    PubMed

    Adimey, Nicole M; Hudak, Christine A; Powell, Jessica R; Bassos-Hull, Kim; Foley, Allen; Farmer, Nicholas A; White, Linda; Minch, Karrie

    2014-04-15

    Documenting the extent of fishery gear interactions is critical to wildlife conservation efforts, especially for reducing entanglements and ingestion. This study summarizes fishery gear interactions involving common bottlenose dolphins (Tursiops truncatus truncatus), Florida manatees (Trichechus manatus latirostris) and sea turtles: loggerhead (Caretta caretta), green turtle (Chelonia mydas), leatherback (Dermochelys coriacea), hawksbill (Eretmochelys imbricata), Kemp's ridley (Lepidochelys kempii), and olive ridley (Lepidochelys olivacea) stranding in Florida waters during 1997-2009. Fishery gear interactions for all species combined were 75.3% hook and line, 18.2% trap pot gear, 4.8% fishing nets, and 1.7% in multiple gears. Total reported fishery gear cases increased over time for dolphins (p<0.05), manatees (p<0.01), loggerheads (p<0.05) and green sea turtles (p<0.05). The proportion of net interaction strandings relative to total strandings for loggerhead sea turtles increased (p<0.05). Additionally, life stage and sex patterns were examined, fishery gear interaction hotspots were identified and generalized linear regression modeling was conducted.

  6. Humphrey Ridley (1653-1708): 17th century evolution in neuroanatomy and selective cerebrovascular injections for cadaver dissection.

    PubMed

    Thakur, Jai Deep; Sonig, Ashish; Chittiboina, Prashant; Khan, Imad Saeed; Wadhwa, Rishi; Nanda, Anil

    2012-08-01

    Humphrey Ridley, M.D. (1653-1708), is a relatively unknown historical figure, belonging to the postmedieval era of neuroanatomical discovery. He was born in the market town of Mansfield, 14 miles from the county of Nottinghamshire, England. After studying at Merton College, Oxford, he pursued medicine at Leiden University in the Netherlands. In 1688, he was incorporated as an M.D. at Cambridge. Ridley authored the first original treatise in English language on neuroanatomy, The Anatomy of the Brain Containing its Mechanisms and Physiology: Together with Some New Discoveries and Corrections of Ancient and Modern Authors upon that Subject. Ridley described the venous anatomy of the eponymous circular sinus in connection with the parasellar compartment. His methods were novel, unique, and effective. To appreciate the venous anatomy, he preferred to perform his anatomical dissections on recently executed criminals who had been hanged. These cadavers had considerable venous engorgement, which made the skull base venous anatomy clearer. To enhance the appearance of the cerebral vasculature further, he used tinged wax and quicksilver in the injections. He set up experimental models to answer questions definitively, in proving that the arachnoid mater is a separate meningeal layer. The first description of the subarachnoid cisterns, blood-brain barrier, and the fifth cranial nerve ganglion with its branches are also attributed to Ridley. This historical vignette revisits Ridley's life and academic work that influenced neuroscience and neurosurgical understanding in its infancy. It is unfortunate that most of his novel contributions have gone unnoticed and uncited. The authors hope that this article will inform the neurosurgical community of Ridley's contributions to the field of neurosurgery.

  7. Distribution and Feeding Behavior of Omorgus suberosus (Coleoptera: Trogidae) in Lepidochelys olivacea Turtle Nests.

    PubMed

    Baena, Martha L; Escobar, Federico; Halffter, Gonzalo; García-Chávez, Juan H

    2015-01-01

    Omorgus suberosus (Fabricius, 1775) has been identified as a potential predator of the eggs of the turtle Lepidochelys olivacea (Eschscholtz, 1829) on one of the main turtle nesting beaches in the world, La Escobilla in Oaxaca, Mexico. This study presents an analysis of the spatio-temporal distribution of the beetle on this beach (in areas of high and low density of L. olivacea nests over two arrival seasons) and an evaluation, under laboratory conditions, of the probability of damage to the turtle eggs by this beetle. O. suberosus adults and larvae exhibited an aggregated pattern at both turtle nest densities; however, aggregation was greater in areas of low nest density, where we found the highest proportion of damaged eggs. Also, there were fluctuations in the temporal distribution of the adult beetles following the arrival of the turtles on the beach. Under laboratory conditions, the beetles quickly damaged both dead eggs and a mixture of live and dead eggs, but were found to consume live eggs more slowly. This suggests that O. suberosus may be recycling organic material; however, its consumption of live eggs may be sufficient in some cases to interrupt the incubation period of the turtle. We intend to apply these results when making decisions regarding the L. olivacea nests on La Escobilla Beach, one of the most important sites for the conservation of this species.

  8. Dimorphic DNA methylation during temperature-dependent sex determination in the sea turtle Lepidochelys olivacea.

    PubMed

    Venegas, Daniela; Marmolejo-Valencia, Alejandro; Valdes-Quezada, Christian; Govenzensky, Tzipe; Recillas-Targa, Félix; Merchant-Larios, Horacio

    2016-09-15

    Sex determination in vertebrates depends on the expression of a conserved network of genes. Sea turtles such as Lepidochelys olivacea have temperature-dependent sex determination. The present work analyses some of the epigenetic processes involved in this. We describe sexual dimorphism in global DNA methylation patterns between ovaries and testes of L. olivacea and show that the differences may arise from a combination of DNA methylation and demethylation events that occur during sex determination. Irrespective of incubation temperature, 5-hydroxymethylcytosine was abundant in the bipotential gonad; however, following sex determination, this modification was no longer found in pre-Sertoli cells in the testes. These changes correlate with the establishment of the sexually dimorphic DNA methylation patterns, down regulation of Sox9 gene expression in ovaries and irreversible gonadal commitment towards a male or female differentiation pathway. Thus, DNA methylation changes may be necessary for the stabilization of the gene expression networks that drive the differentiation of the bipotential gonad to form either an ovary or a testis in L. olivacea and probably among other species that manifest temperature-dependent sex determination.

  9. Distribution and Feeding Behavior of Omorgus suberosus (Coleoptera: Trogidae) in Lepidochelys olivacea Turtle Nests

    PubMed Central

    Baena, Martha L.; Escobar, Federico; Halffter, Gonzalo; García–Chávez, Juan H.

    2015-01-01

    Omorgus suberosus (Fabricius, 1775) has been identified as a potential predator of the eggs of the turtle Lepidochelys olivacea (Eschscholtz, 1829) on one of the main turtle nesting beaches in the world, La Escobilla in Oaxaca, Mexico. This study presents an analysis of the spatio–temporal distribution of the beetle on this beach (in areas of high and low density of L. olivacea nests over two arrival seasons) and an evaluation, under laboratory conditions, of the probability of damage to the turtle eggs by this beetle. O. suberosus adults and larvae exhibited an aggregated pattern at both turtle nest densities; however, aggregation was greater in areas of low nest density, where we found the highest proportion of damaged eggs. Also, there were fluctuations in the temporal distribution of the adult beetles following the arrival of the turtles on the beach. Under laboratory conditions, the beetles quickly damaged both dead eggs and a mixture of live and dead eggs, but were found to consume live eggs more slowly. This suggests that O. suberosus may be recycling organic material; however, its consumption of live eggs may be sufficient in some cases to interrupt the incubation period of the turtle. We intend to apply these results when making decisions regarding the L. olivacea nests on La Escobilla Beach, one of the most important sites for the conservation of this species. PMID:26422148

  10. Deepwater Horizon oil spill impacts on sea turtles could span the Atlantic.

    PubMed

    Putman, Nathan F; Abreu-Grobois, F Alberto; Iturbe-Darkistade, Iñaky; Putman, Emily M; Richards, Paul M; Verley, Philippe

    2015-12-01

    We investigated the extent that the 2010 Deepwater Horizon oil spill potentially affected oceanic-stage sea turtles from populations across the Atlantic. Within an ocean-circulation model, particles were backtracked from the Gulf of Mexico spill site to determine the probability of young turtles arriving in this area from major nesting beaches. The abundance of turtles in the vicinity of the oil spill was derived by forward-tracking particles from focal beaches and integrating population size, oceanic-stage duration and stage-specific survival rates. Simulations indicated that 321 401 (66 199-397 864) green (Chelonia mydas), loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) turtles were likely within the spill site. These predictions compared favourably with estimates from in-water observations recently made available to the public (though our initial predictions for Kemp's ridley were substantially lower than in-water estimates, better agreement was obtained with modifications to mimic behaviour of young Kemp's ridley turtles in the northern Gulf). Simulations predicted 75.2% (71.9-76.3%) of turtles came from Mexico, 14.8% (11-18%) from Costa Rica, 5.9% (4.8-7.9%) from countries in northern South America, 3.4% (2.4-3.5%) from the United States and 1.6% (0.6-2.0%) from West African countries. Thus, the spill's impacts may extend far beyond the current focus on the northern Gulf of Mexico.

  11. Sir Nicholas Harold Lloyd Ridley: 10 July 1906 - 25 May 2001.

    PubMed

    Apple, David J

    2007-01-01

    Sir Harold Ridley invented and refined the modern miracle of replacing lenses obscured by cataracts with plastic optical lenses, thus rendering a complete cataract cure. This operation, broadly termed the cataract-intraocular lens (IOL) operation, has since brought sight to many millions of people throughout the world, and continues to improve the quality of life of more than 10 million patients worldwide each year. Ridley not only launched this powerful and irreversible forward movement in the field of ophthalmology and the visual sciences, but through it he also helped give birth to the exciting and new field of artificial biodevice implantation as well as transplantation techniques now applied to many other organs and tissues of the body. He has therefore been credited with healing to create the relatively new specialty of biomedical engineering. Few of the millions of patients worldwide who now enjoy the benefits of the modern cataract - IOL operation are aware of the origin of this innovation. Indeed, few eye care professionals - even ophthalmic surgeons who implant them almost daily - are aware of the origin of the IOL - an invention that, as Harold himself liked to say, 'cured aphakia'. (The word aphakia comes from teh Greek, meaning absence of lens, the situation that occurs when a cataractous lens is surgically removed.)

  12. Two models of cross polar cap potential saturation compared: Siscoe-Hill model versus Kivelson-Ridley model

    NASA Astrophysics Data System (ADS)

    Gao, Ye; Kivelson, Margaret G.; Walker, Raymond J.

    2013-02-01

    The cross polar cap potential is considered an instantaneous monitor of the rate at which magnetic flux couples the solar wind to the Earth's magnetosphere-ionosphere system. Studies have shown that the cross polar cap potential responds linearly to the solar wind electric field under nominal solar wind conditions but asymptotes to the order of 200 kV for large electric field. Saturation of the cross polar cap potential is also found to occur in MHD simulations. Several mechanisms have been proposed to explain this phenomenon. Two well-developed models are those of Siscoe et al. (2002), herein referred to as the Siscoe-Hill model, and of Kivelson and Ridley (2008), herein referred to as the Kivelson-Ridley model. In this study, we compare the mathematical formulas as well as the predictions of the two models with data. We find that the two models predict similar saturation limits. Their difference can be expressed in terms of a factor, which is close to unity during a saturation interval. A survey of the differences in the model predictions show that, on average, the potential of the Kivelson-Ridley model is smaller than that of the Siscoe-Hill model by 10 kV. Measurements of AMIE, DMSP, PC index, and SuperDARN are used to differentiate between the two models. However, given the uncertainties of the measurements, it is impossible to conclude that one model does a better job than the other of predicting the observed cross polar cap potentials.

  13. Mercury in blood and eggs of the sea turtle Lepidochelys olivacea from a nesting colony in Oaxaca, Mexico.

    PubMed

    Páez-Osuna, F; Calderón-Campuzano, M F; Soto-Jiménez, M F; Ruelas-Inzunza, J

    2011-06-01

    Mercury concentrations were assessed in the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico; 25 female turtles were sampled, a total of 250 eggs were collected during the season 2005-2006. Higher concentrations were found in yolk fraction, while in blood and albumen mean levels were below of 0.0010μg g(-1) dry wt. On the basis of one nesting season, the maternal transfer of Hg via eggs-laying was estimated in 2.0±1.1%. According to international norms, the health of this population and its habitats is acceptable for Hg and corresponds to baseline levels of a nearly pristine environment.

  14. Habitat use and diving behaviour of gravid olive ridley sea turtles under riverine conditions in French Guiana

    NASA Astrophysics Data System (ADS)

    Chambault, Philippine; Giraudou, Lucie; de Thoisy, Benoît; Bonola, Marc; Kelle, Laurent; Reis, Virginie Dos; Blanchard, Fabian; Le Maho, Yvon; Chevallier, Damien

    2017-01-01

    The identification of the inter-nesting habitat used by gravid sea turtles has become a crucial factor in their protection. Their aggregation in large groups of individuals during the inter-nesting period exposes them to increased threats to their survival - particularly along the French Guiana shield, where intense legal and illegal fisheries occur. Among the three sea turtle species nesting in French Guiana, the olive ridley appears to have the most generalist diet, showing strong behavioural plasticity according to the environment encountered. The large amounts of sediments that are continuously discharged by the Amazon River create a very unusual habitat for olive ridleys, i.e. turbid waters with low salinity. This study assesses the behavioural adjustments of 20 adult female olive ridleys under such riverine conditions. Individuals were tracked by satellite from Remire-Montjoly rookery in French Guiana using tags that recorded the location and diving parameters of individuals, as well as the immediate environment of the turtles including the in situ temperature and salinity. Data concerning potential preys was provided via collection of epifauna by a trawler. Multiple behavioural shifts were observed in both horizontal and vertical dimensions. During the first half of the inter-nesting season, the turtles moved away from the nesting beach (21.9 ± 24.7 km), performing deeper (12.6 ± 7.4 m) and longer (29.7 ± 21.0 min) dives than during the second half of the period (7.4 ± 7.8 km, 10.4 ± 4.9 m and 25.9 ± 19.3 min). Olive ridleys remained in waters that were warm (range: 26-33 °C) and which fluctuated in terms of salinity (range: 19.5-36.4 psu), in a relatively small estuarine habitat covering 423 km2. If olive ridleys were foraging during this period, the potential preys that might be available were mostly crustaceans (43%) and fish (39%), as expected for the diet of this generalist species during this period. This study highlights the numerous

  15. The Head and Neck Anatomy of Sea Turtles (Cryptodira: Chelonioidea) and Skull Shape in Testudines

    PubMed Central

    Jones, Marc E. H.; Werneburg, Ingmar; Curtis, Neil; Penrose, Rod; O’Higgins, Paul; Fagan, Michael J.; Evans, Susan E.

    2012-01-01

    Background Sea turtles (Chelonoidea) are a charismatic group of marine reptiles that occupy a range of important ecological roles. However, the diversity and evolution of their feeding anatomy remain incompletely known. Methodology/Principal Findings Using computed tomography and classical comparative anatomy we describe the cranial anatomy in two sea turtles, the loggerhead (Caretta caretta) and Kemp’s ridley (Lepidochelys kempii), for a better understanding of sea turtle functional anatomy and morphological variation. In both taxa the temporal region of the skull is enclosed by bone and the jaw joint structure and muscle arrangement indicate that palinal jaw movement is possible. The tongue is relatively small, and the hyoid apparatus is not as conspicuous as in some freshwater aquatic turtles. We find several similarities between the muscles of C. caretta and L. kempii, but comparison with other turtles suggests only one of these characters may be derived: connection of the m. adductor mandibulae internus into the Pars intramandibularis via the Zwischensehne. The large fleshy origin of the m. adductor mandibulae externus Pars superficialis from the jugal seems to be a characteristic feature of sea turtles. Conclusions/Significance In C. caretta and L. kempii the ability to suction feed does not seem to be as well developed as that found in some freshwater aquatic turtles. Instead both have skulls suited to forceful biting. This is consistent with the observation that both taxa tend to feed on relatively slow moving but sometimes armoured prey. The broad fleshy origin of the m. adductor mandibulae externus Pars superficialis may be linked to thecheek region being almost fully enclosed in bone but the relationship is complex. PMID:23144831

  16. Forecasting range expansion into ecological traps: climate-mediated shifts in sea turtle nesting beaches and human development.

    PubMed

    Pike, David A

    2013-10-01

    Some species are adapting to changing environments by expanding their geographic ranges. Understanding whether range shifts will be accompanied by increased exposure to other threats is crucial to predicting when and where new populations could successfully establish. If species overlap to a greater extent with human development under climate change, this could form ecological traps which are attractive to dispersing individuals, but the use of which substantially reduces fitness. Until recently, the core nesting range for the Critically Endangered Kemp's ridley sea turtle (Lepidochelys kempii) was ca. 1000 km of sparsely populated coastline in Tamaulipas, Mexico. Over the past twenty-five years, this species has expanded its range into populated areas of coastal Florida (>1500 km outside the historical range), where nesting now occurs annually. Suitable Kemp's ridley nesting habitat has persisted for at least 140 000 years in the western Gulf of Mexico, and climate change models predict further nesting range expansion into the eastern Gulf of Mexico and northern Atlantic Ocean. Range expansion is 6-12% more likely to occur along uninhabited stretches of coastline than are current nesting beaches, suggesting that novel nesting areas will not be associated with high levels of anthropogenic disturbance. Although the high breeding-site fidelity of some migratory species could limit adaptation to climate change, rapid population recovery following effective conservation measures may enhance opportunities for range expansion. Anticipating the interactive effects of past or contemporary conservation measures, climate change, and future human activities will help focus long-term conservation strategies.

  17. 75 FR 22106 - Endangered Species; File No. 14510

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-27

    ... (Chelonia mydas), loggerhead (Caretta caretta), olive ridley (Lepidochelys olivacea), and leatherback..., inject tetracycline, and release up to: ten green, one olive ridley, and three loggerhead sea turtles taken in power plant entrainments; four green, one olive ridley, one loggerhead, and two leatherback...

  18. Peer-Reviewed Research and the IEP: Implications of "Ridley School District v. M.R. and J.R. ex rel. E.R." (2012)

    ERIC Educational Resources Information Center

    Yell, Mitchell L.; Katsiyannis, Antonis; Losinski, Mickey; Marshall, Kelsey

    2016-01-01

    This article examines a case out of the U.S. Court of Appeals for the Third Circuit: "Ridley School District v. M.R and J.R. ex rel. E.R." (2012). The case is the first circuit court case in which the Individuals with Disabilities Education Improvement Act requirement that special education services be based on peer-reviewed research…

  19. Deepwater Horizon oil spill impacts on sea turtles could span the Atlantic

    PubMed Central

    Putman, Nathan F.; Abreu-Grobois, F. Alberto; Iturbe-Darkistade, Iñaky; Putman, Emily M.; Richards, Paul M.; Verley, Philippe

    2015-01-01

    We investigated the extent that the 2010 Deepwater Horizon oil spill potentially affected oceanic-stage sea turtles from populations across the Atlantic. Within an ocean-circulation model, particles were backtracked from the Gulf of Mexico spill site to determine the probability of young turtles arriving in this area from major nesting beaches. The abundance of turtles in the vicinity of the oil spill was derived by forward-tracking particles from focal beaches and integrating population size, oceanic-stage duration and stage-specific survival rates. Simulations indicated that 321 401 (66 199–397 864) green (Chelonia mydas), loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) turtles were likely within the spill site. These predictions compared favourably with estimates from in-water observations recently made available to the public (though our initial predictions for Kemp's ridley were substantially lower than in-water estimates, better agreement was obtained with modifications to mimic behaviour of young Kemp's ridley turtles in the northern Gulf). Simulations predicted 75.2% (71.9–76.3%) of turtles came from Mexico, 14.8% (11–18%) from Costa Rica, 5.9% (4.8–7.9%) from countries in northern South America, 3.4% (2.4–3.5%) from the United States and 1.6% (0.6–2.0%) from West African countries. Thus, the spill's impacts may extend far beyond the current focus on the northern Gulf of Mexico. PMID:26701754

  20. Metal contents of marine turtle eggs (Chelonia mydas; Lepidochelys olivacea) from the tropical eastern pacific and the implications for human health.

    PubMed

    Ross, David A; Guzmán, Héctor M; Van Hinsberg, Vincent J; Potvin, Catherine

    2016-10-02

    Concentrations of eight elements were measured in Chelonia mydas and Lepidochelys olivacea eggs collected along the Pacific coast of Panama. Manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), and mercury (Hg) concentrations were similar to previous reports of these species from around the world, while lead (Pb) was lower than previous reports. Cd posed the highest health risk to people who regularly eat the eggs, with average consumption rates leading to target hazard quotients (THQ) of up to 0.35 ± 0.15. Our conclusions indicate that current turtle egg consumption in isolated, coastal Pacific communities may pose a health concern for young children, and that youth and young adults should limit their consumption of turtle eggs to reduce their total intake of nonessential metals.

  1. Taxonomy of the Caribbean sponge Dragmacidon reticulatum (Ridley & Dendy, 1886) (Porifera, Demospongiae, Axinellida), with the description of a new species.

    PubMed

    Zea, Sven; Pulido, Alejandra

    2016-05-25

    Although there is a long history of taxonomic investigation in Caribbean sponges, there are still many undescribed species. Furthermore, field observations and corroborating morphological analyses are revealing that what was believed to be single, somewhat variable species, may consist of two or more species, often easier to distinguish once well characterized. This is the case for Dragmacidon reticulatum (Ridley & Dendy, 1886) (Porifera, Demospongiae, Axinellida, Axinellidae), a rather well-known sponge, with an ample distribution and presence in rocky and reef environments of the tropical and subtropical Western Atlantic, with local records in the majority of the countries of the area, from Bermuda to Brazil. Field observations and a detailed review of material from different areas, including some type specimens, led us to the distinction of two different species in terms of external morphology, size of spicules, and skeletal architecture. The distinction was confirmed in the Bahamas and Santa Marta, Colombia, where the two species coexist. One of the species is Dragmacidon reticulatum sensu stricto, but for the other there is need to erect a new name, for which we propose Dragmacidon alvarezae n. sp. The purpose of the present work is to describe, illustrate and compare these two species.

  2. Olive Ridley Sea Turtle Hatching Success as a Function of the Microbial Abundance in Nest Sand at Ostional, Costa Rica

    PubMed Central

    Bézy, Vanessa S.; Valverde, Roldán A.; Plante, Craig J.

    2015-01-01

    Several studies have suggested that significant embryo mortality is caused by microbes, while high microbial loads are generated by the decomposition of eggs broken by later nesting turtles. This occurs commonly when nesting density is high, especially during mass nesting events (arribadas). However, no previous research has directly quantified microbial abundance and the associated effects on sea turtle hatching success at a nesting beach. The aim of this study was to test the hypothesis that the microbial abundance in olive ridley sea turtle nest sand affects the hatching success at Ostional, Costa Rica. We applied experimental treatments to alter the microbial abundance within the sand into which nests were relocated. We monitored temperature, oxygen, and organic matter content throughout the incubation period and quantified the microbial abundance within the nest sand using a quantitative polymerase chain reaction (qPCR) molecular analysis. The most successful treatment in increasing hatching success was the removal and replacement of nest sand. We found a negative correlation between hatching success and fungal abundance (fungal 18S rRNA gene copies g-1 nest sand). Of secondary importance in determining hatching success was the abundance of bacteria (bacterial 16S rRNA gene copies g-1 g-1 nest sand). Our data are consistent with the hypothesis that high microbial activity is responsible for the lower hatching success observed at Ostional beach. Furthermore, the underlying mechanism appears to be the deprivation of oxygen and exposure to higher temperatures resulting from microbial decomposition in the nest. PMID:25714355

  3. Dehydration as an effective treatment for brevetoxicosis in loggerhead sea turtles (Caretta caretta).

    PubMed

    Manire, Charles A; Anderson, Eric T; Byrd, Lynne; Fauquier, Deborah A

    2013-06-01

    Harmful algal blooms are known to cause morbidity and mortality to a large number of marine and estuarine organisms worldwide, including fish and marine mammals, birds, and turtles. The effects of these algal blooms on marine organisms are due to the various toxins produced by the different algal species. In southwest Florida, frequent blooms of the dinoflagellate Karenia brevis, which produces neurotoxins known as brevetoxins, cause widespread fish kills and affect many marine animals. In 2005-2007, numerous sea turtles of several species underwent treatment for brevetoxicosis at the Sea Turtle Rehabilitation Hospital. In green sea turtles, Chelonia mydas, and Kemp's ridley sea turtles, Lepidochelys kempii, symptoms associated with brevetoxicosis were limited to neurologic signs, such as the inability to control the head (head bobbing) and nervous twitching. For these turtles, treatment involved removing the turtles from the environment containing the toxins and providing short-term supportive care. In loggerhead sea turtles, Caretta caretta, symptoms were more generalized; thus, a similar approach was unsuccessful, as was routine treatment for general toxicosis. Loggerhead sea turtles had more extreme neurologic symptoms including coma, and other symptoms that included generalized edema, conjunctival edema, and cloacal or penile prolapse. Treatment of brevetoxicosis in loggerhead sea turtles required a therapeutic regimen that initially included dehydration and systemic antihistamine treatment followed by supportive care.

  4. Tracking sea turtles in the Everglades

    USGS Publications Warehouse

    Hart, Kristin M.

    2008-01-01

    The U.S. Geological Survey (USGS) has a long history of conducting research on threatened, endangered, and at-risk species inhabiting both terrestrial and marine environments, particularly those found within national parks and protected areas. In the coastal Gulf of Mexico region, for example, USGS scientist Donna Shaver at Padre Island National Seashore in Texas has focused on “headstarting” hatchlings of the rare Kemp’s ridley sea turtle (Lepidochelys kempii). She is also analyzing trends in sea turtle strandings onshore and interactions with Gulf shrimp fisheries. Along south Florida’s Gulf coast, the USGS has focused on research and monitoring for managing the greater Everglades ecosystem. One novel project involves the endangered green sea turtle (Chelonia mydas). The ecology and movements of adult green turtles are reasonably well understood, largely due to decades of nesting beach monitoring by a network of researchers and volunteers. In contrast, relatively little is known about the habitat requirements and movements of juvenile and subadult sea turtles of any species in their aquatic environment.

  5. Level II scour analysis for Bridge 37 (DUXBTH00120037) on Town Highway 12, crossing Ridley Brook, Duxbury, Vermont

    USGS Publications Warehouse

    Wild, Emily C.; Ivanhoff, Michael A.

    1997-01-01

    This report provides the results of a detailed Level II analysis of scour potential at structure DUXBTH00120037 on Town Highway 12 crossing Ridley Brook, Duxbury, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). Results of a Level I scour investigation also are included in Appendix E of this report. A Level I investigation provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and is found in Appendix D. The site is in the Green Mountain section of the New England physiographic province in north central Vermont. The 10.1-mi2 drainage area is in a predominantly rural and forested basin. In the vicinity of the study site, the surface cover is forest upstream and downstream of the bridge. In the study area, Ridley Brook has an incised, straight channel with a slope of approximately 0.04 ft/ft, an average channel top width of 67 ft and an average bank height of 9 ft. The channel bed material ranges from gravel to boulders with a median grain size (D50) of 123 mm (0.404 ft). The geomorphic assessment at the time of the Level I and Level II site visit on July 1, 1996, indicated that the reach was stable. The Town Highway 12 crossing of Ridley Brook is a 33-ft-long, two-lane bridge consisting of five 30-ft steel rolled beams (Vermont Agency of Transportation, written communication, October 13, 1995). The opening length of the structure parallel to the bridge face is 30 ft. The bridge is supported by vertical, concrete abutments with wingwalls. The channel is skewed approximately 50 degrees to the opening while the measured opening-skew-to-roadway is 20 degrees. A scour hole 2 ft deeper than the mean thalweg depth was observed along the right abutment and downstream

  6. Lead in blood and eggs of the sea turtle, Lepidochelys olivacea, from the Eastern Pacific: concentration, isotopic composition and maternal transfer.

    PubMed

    Páez-Osuna, F; Calderón-Campuzano, M F; Soto-Jiménez, M F; Ruelas-Inzunza, J R

    2010-03-01

    Concentrations of lead were assessed in the sea turtle, Lepidochelys olivacea, from a nesting colony of the Eastern Pacific. Twenty-five female turtles were sampled and a total of 250 eggs were collected during the "arribada" event of the 2005-2006 season. Considering the nesting season, the maternal transfer of lead (Pb) via egg-laying, in terms of metal burden in whole body, was 0.5%. Pb concentrations (in dry weight) in blood (0.95+/-0.18microgg(-1)) and egg samples (yolk, 0.80+/-0.10microg g(-1); albumen, 1.08+/-0.20microg g(-1); eggshell, 1.05+/-0.20microg g(-1)) were comparable or even lower than those found in other sea turtles. The isotope ratios ((206)Pb/(207)Pb and (206)Pb/(208)Pb) in blood (1.183+/-0.0006 and 2.452+/-0.0006, respectively) were comparable to that of natural Pb-bearing bedrock in Mexico (1.188+/-0.005 and 2.455+/-0.008, respectively). According to international norms of Pb, the health of this population and its habitats is acceptable for Pb and corresponds to basic levels of a nearly pristine environment.

  7. Trace metals (Cd, Cu, Ni, and Zn) in blood and eggs of the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico.

    PubMed

    Páez-Osuna, Federico; Calderón-Campuzano, María F; Soto-Jiménez, Martín F; Ruelas-Inzunza, Jorge R

    2010-11-01

    Trace metals (Cd, Cu, Ni, and Zn) concentrations were assessed in the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico. Twenty-five female turtles were sampled, a total of 250 eggs were collected during the "arribada" event of the 2005-2006 season. Zn concentrations were highest in the yolk [72.3 ± 10.9 μg/g dry weight (dw)] and blood (58.4 ± 4.7 μg/g dw), whereas Ni concentrations were highest in the shell (48.5 ± 12.9 μg/g dw). The mean concentrations of Cu, and Cd in the analyzed tissues were lower than those reported in other sea turtle species. However, Zn and Ni concentrations in the yolk and shell, respectively, had the same distribution pattern observed at loggerhead and green turtles. On the basis of one nesting season, the maternal transfer and/or the excretion rates of trace metals via eggs-laying, estimated in terms of metal burdens in whole body, were 0.2, 7.8, 3.4, and 21.5% for Cd, Cu, Zn, and Ni, respectively.

  8. Expression profiles of Dax1, Dmrt1, and Sox9 during temperature sex determination in gonads of the sea turtle Lepidochelys olivacea.

    PubMed

    Torres Maldonado, L C; Landa Piedra, A; Moreno Mendoza, N; Marmolejo Valencia, A; Meza Martínez, A; Merchant Larios, H

    2002-10-15

    Sex determination is controlled either by genetic or environmental factors. In mammals Sry initiates determination but no homologue of this gene exists in non-mammalian species. Other genes of the mammalian sex-determining pathway have been identified in gonads of different vertebrates. Sox9, Dax1, and Dmrt1 are expressed at the onset of gonadal development in birds and reptiles. In the sea turtle Lepidochelys olivacea, a species with temperature sex determination (TSD), Sox9 is expressed in undifferentiated gonads at male- (MPT) or female-promoting temperatures (FPT). At MPT, Sox9 remains expressed in male gonads, but at FPT it is downregulated coinciding with the onset of the ovarian morphologic differentiation and female sex determination. At MPT however, male sex is determined early than at FPT in still undifferentiated gonads suggesting that other genes maintain Sox9 expression in testis. Here we used RT-PCR to study the expression profiles of Dax1, Dmrt1, and Sox9 in gonads of embryos of L. olivacea incubated at MPT or at FPT. The profiles were correlated with sex determination during and after the temperature-sensitive period (TSP). Dax1 maintained similar levels at both temperatures during the TSP. The Dax1 expression level increased significantly in ovaries compared to testes at stage 27, once they were morphologically distinct. The expression levels of Dmrt1 were higher at MPT than at FPT at all stages, in contrast with Sox9 levels which were similar at both temperatures at stages 23-25. Together, current results suggest that, whereas Dax1 is not involved in TSD in L. olivacea, upregulation of Dmrt1 and downregulation of Sox9 may play a role in male and female sex determination, respectively.

  9. Three who made an association: I. Sir William Osler, 1849-1919. II. George Milbry Gould, 1848-1922. III. Margaret Ridley Charlton, 1858-1931 and the founding of the Medical Library Association, Philadelphia, 1898.

    PubMed Central

    Groen, F K

    1998-01-01

    The careers and personalities of the three founders of the Medical Library Association, Sir William Osler, George Milbry Gould, and Margaret Ridley Charlton are outlined, followed by a review of their role in the founding of the association. The career of Sir William Osler is well documented in existing literature, both in medical history and medical librarianship; the biographies of George Milbry Gould and Margaret Ridley Charlton are less known, and this article describes their lives in relation to the founding of the association. The issue of responsibility for the association's founding is explored, and primary recognition is attributed to Margaret Charlton. The author attempts to follow the tradition of Harvey Cushing in his The Life of Sir William Osler in allowing the characters to speak in their own words as much as possible. Images PMID:9578937

  10. Three who made an association: I. Sir William Osler, 1849-1919 II. George Milbry Gould, 1848-1922 III. Margaret Ridley Charlton, 1858-1931 and the founding of the Medical Library Association, Philadelphia, 1898.

    PubMed Central

    Groen, F K

    1996-01-01

    The careers and personalities of the three founders of the Medical Library Association, Sir William Osler, George Milbry Gould, and Margaret Ridley Charlton are outlined, followed by a review of their role in the founding of the association. The career of Sir William Osler is well documented in existing literature, both in medical history and medical librarianship; the biographies of George Milbry Gould and Margaret Ridley Charlton are less known, and this article describes their lives in relation to the founding of the association. The issue of responsibility for the association's founding is explored, and primary recognition is attributed to Margaret Charlton. The author attempts to follow the tradition of Harvey Cushing in his The Life of Sir William Osler in allowing the characters to speak in their own words as much as possible. Images PMID:8883979

  11. Direct evidence of swimming demonstrates active dispersal in the sea turtle "lost years".

    PubMed

    Putman, Nathan F; Mansfield, Katherine L

    2015-05-04

    Although oceanic dispersal in larval and juvenile marine animals is widely studied, the relative contributions of swimming behavior and ocean currents to movements and distribution are poorly understood [1-4]. The sea turtle "lost years" [5] (often referred to as the surface-pelagic [6] or oceanic [7] stage) are a classic example. Upon hatching, young turtles migrate offshore and are rarely observed until they return to coastal waters as larger juveniles [5]. Sightings of small turtles downcurrent of nesting beaches and in association with drifting organisms (e.g., Sargassum algae) led to this stage being described as a "passive migration" during which turtles' movements are dictated by ocean currents [5-10]. However, laboratory and modeling studies suggest that dispersal trajectories might also be shaped by oriented swimming [11-15]. Here, we use an experimental approach designed to directly test the passive-migration hypothesis by deploying pairs of surface drifters alongside small green (Chelonia mydas) and Kemp's ridley (Lepidochelys kempii) wild-caught turtles, tracking their movements via satellite telemetry. We conclusively demonstrate that these turtles do not behave as passive drifters. In nearly all cases, drifter trajectories were uncharacteristic of turtle trajectories. Species-specific and location-dependent oriented swimming behavior, inferred by subtracting track velocity from modeled ocean velocity, contributed substantially to individual movement and distribution. These findings highlight the importance of in situ observations for depicting the dispersal of weakly swimming animals. Such observations, paired with information on the mechanisms of orientation, will likely allow for more accurate predictions of the ecological and evolutionary processes shaped by animal movement.

  12. 75 FR 71670 - Endangered Species; File No. 15606

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-24

    ... in Gulf of Mexico waters. The purposes of these projects are to: (1) Examine green sea turtle assemblages in sea grass habitats in Texas; (2) determine trends in seasonal abundance and movement of green... applied in due form for a permit to take green (Chelonia mydas), Kemp's ridley (Lepidochelys...

  13. Sources of Vibrio mimicus Contamination of Turtle Eggs

    PubMed Central

    Acuña, María T.; Díaz, Gerardo; Bolaños, Hilda; Barquero, Candy; Sánchez, Olga; Sánchez, Luz M.; Mora, Grettel; Chaves, Anny; Campos, Elena

    1999-01-01

    Vibrio mimicus contamination of sand increased significantly during the arrival of the olive ridley sea turtles (Lepidochelys olivacea) at Ostional anidation beach, Costa Rica. Statistical analysis supports that eggs are contaminated with V. mimicus by contact with the sand nest. V. mimicus was isolated from eggs of all nests tested, and ctxA+ strains were found in 31% of the nests, all of which were near the estuary. PMID:9872804

  14. Environmental effects of dredging: Alternative dredging equipment and operational methods to minimize sea turtle mortalities. Technical notes

    SciTech Connect

    Dickerson, D.D.; Nelson, D.A.

    1990-12-01

    Five species of sea turtles occur along the United States coastlines and are listed as threatened or endangered. The loggerhead sea turtle (Caretta caretta) is listed as threatened, while the Kemp`s ridley (Lepidochelys kenipi), the hawksbill (Eretmochelys imbricata), and the leatherback (Dermochelys coriacea) are all less abundant and listed as endangered. Florida breeding populations of the green sea turtle (Chelonia mydas) are listed as endangered, but green turtles in other US waters are considered threatened. The National Marine Fisheries Service (NMFS) has determined, based on the best available information, that because of their life cycle and behavioral patterns only the loggerhead, the green, and the Kemp`s ridley are put at risk by hopper dredging activities (Studt 1987).

  15. Marine turtles of the Gal?pagos Islands and adjacent areas of the eastern Pacific on the basis of observations made by J.R. Slevin 1905-1906

    USGS Publications Warehouse

    Fritts, T.H.

    1981-01-01

    The field notes of J. R. Slevin written during the expedition of the California Academy of Sciences to the Galapagos Islands in 1905-1096 contain previously unavailable data on the marine turtles of the eastern Pacific. 'Land basking' by green turtles in Galapagos was predominately, if not exclusively, a female behavior. These terrestrial emergences were not concentrated in the major reproductive season of Galapagos turtles. Female Chelonia were also collected on shore during daylight hours on Socorro Island southwest of Baja California, Mexico. Chelonia, green turtles, were observed to feed on seaweed, the leaves and shoots of mangrove trees, and the leaves of another unidentified shoreline shrub. Comparative data on the gonads of dark and yellow turtles indicated that the latter did not breed in Galapagos during Slevin's stay. Lepidochelys olivacea, the olive ridley, was recorded in Galapagos waters and fed on fish eggs

  16. Lipids and proteins in the Rathke's gland secretions of the North American mud turtle (Kinosternon subrubrum)

    USGS Publications Warehouse

    Seifert, W.E.; Gotte, S.W.; Leto, T.L.; Weldon, P.J.

    1994-01-01

    Lipids and proteins in the Rathke's gland secretions of the North American mud turtle (Kinosternon subrubrum, Kinosternidae) were analyzed by gas chromatography-mass spectrometry (GC-MS) and SDS-polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Analysis by GC-MS indicates 2,3-dihydroxypropanal and C3?C24 free or esterified fatty acids. Analysis by SDS-PAGE indicates a major protein component with an approximate molecular mass of 60 kDa and minor components ranging from ca. 23 to 34 kDa. The major component of K. subrubrum glandular secretions exhibits a mobility that matches that of the Kemp's ridley sea turtle (Lepidochelys kempi, Cheloniidae), suggesting that these proteins are evolutionarily conserved.

  17. Asymmetry of righting reflexes in sea turtles and its behavioral correlates.

    PubMed

    Malashichev, Yegor

    2016-04-01

    The righting responses, when the animal rights itself over one side of the body after been overturned on the back, are one of the simplest ways to test for laterality, especially in lower vertebrates. In anuran amphibians unilateral preferences in righting responses correlated to the degree of the use of alternating-limb (asynchronous) movements during locomotion. Turtles is one of the underrepresented vertebrate groups in the studies of laterality, while possess also different types of locomotion (with synchronous or asynchronous use of the contralateral limbs), which allows testing the hypothesis on functional relationship between the mode of locomotion and the strength of laterality. We studied two species of sea turtles, Green turtle (Chelonia mydas) and Olive Ridley turtle (Lepidochelys olivacea), which differ from the majority of other representatives of the order in that they mostly utilize synchronous locomotion, when all four limbs move simultaneously in strokes (scratching). In righting response tests turtles demonstrated individual and weak population level laterality, which differed in strength. The Green turtle was less lateralized with the majority of individuals being ambipreferent. The Olive Ridley turtle had a greater number of lateralized individuals and a greater average strength of laterality. Interspecies comparison to land tortoises, which use only asynchronous (alternating-limb) walking (crawling), confirmed the rule found in amphibians: the more asynchronous locomotion is used, the greater is the strength of laterality in righting. Hence, data from turtles and amphibians may represent a phenomenon common for all quadruped vertebrates. We also discuss possible biomechanical and neurological correlates of this evolutionary change in locomotory patterns and lateralization in sea turtles when adapting to sea life.

  18. Respiration in Neonate Sea Turtles

    PubMed Central

    Paladino, Frank V.; Strohl, Kingman P.; Pilar Santidrián, T.; Klann, Kenneth; Spotila, James R.

    2007-01-01

    The pattern and control of respiration is virtually unknown in hatchling sea turtles. Using incubator-raised turtles, we measured oxygen consumption, frequency, tidal volume, and minute volume for leatherback (Dermochelys coriacea) and olive ridley (Lepidochelys olivacea) turtle hatchlings for the first six days after pipping. In addition, we tested the hatchlings’ response to hypercapnic, hyperoxic, and hypoxic challenges over this time period. Hatchling sea turtles generally showed resting ventilation characteristics that are similar to those of adults: a single breath followed by a long respiratory pause, slow frequency, and high metabolic rate. With hypercapnic challenge, both species responded primarily by elevating respiratory frequency via a decrease in the non-ventilatory period. Leatherback resting tidal volume increased with age but otherwise, neither species’ resting respiratory pattern nor response to gas challenge changed significantly over the first few days after hatching. At the time of nest emergence, sea turtles have achieved a respiratory pattern that is similar to that of actively diving adults. PMID:17258487

  19. Biotransformation of 2,2',5,5'-tetrachlorobiphenyl (PCB 52) and 3,3',4,4'-tetrachlorobiphenyl (PCB 77) by liver microsomes from four species of sea turtles.

    PubMed

    Richardson, Kristine L; Schlenk, Daniel

    2011-05-16

    The rates of oxidative metabolism of two tetrachlorobiphenyl congeners were determined in hepatic microsomes from four species of sea turtles, green (Chelonia mydas), olive ridley (Lepidochelys olivacea), loggerhead (Caretta caretta), and hawksbill (Eretmochelys imbricata). Hydroxylation of 3,3',4,4'-tetrachlorobiphenyl (PCB 77), an ortho-meta unsubstituted rodent cytochrome P450 (P450) 1A substrate PCB, was not observed in sea turtle microsomes. Sea turtle microsomes hydroxylated 2,2',5,5'-tetrachlorobiphenyl (PCB 52), a meta-para unsubstituted rodent P450 family 2 substrate PCB, at rates ranging from less than 0.5 to 53 pmol/min/mg protein. The P450 inhibitor ketoconazole inhibited hydroxylation of PCB 52, supporting the role of P450 catalysis. Sea turtle PCB 52 hydroxlyation rates strongly correlated with immunodetected P450 family 2-like and less so with P450 family 3-like hepatic proteins. Testosterone 6β-, 16α-, 16β-hydroxylase activities were also significantly correlated with the expression of these enzymes, indicating that P450 family 2 or P450 family 3 proteins are responsible for PCB hydroxylation in sea turtles. This study indicated species-specific PCB biotransformation in sea turtles and preferential elimination of meta-para unsubstituted PCB congeners over ortho-meta unsubstituted PCB congeners consistent with PCB accumulation patterns observed in tissues of sea turtles.

  20. Operational surface currents derived from satellite altimeters and scatterometers; Pilot Study for the Tropical Pacific

    NASA Astrophysics Data System (ADS)

    Lagerloef, G.

    1 and diagnose model errors. Another immediate application of these data relates to fisheries management and ma- rine wildlife research in the region. Movements of several species of sea turtle in the tropical region are being tracked by satellite with System Argos. Results show that some turtle tracks follow meandering portions of the North Equatorial Current and North Equatorial Counter Current. The surface current data allow researchers to exam- ine the oceanography of the habitat these turtles are using, for example, and evaluate to what extent they are using the equatorial currents and regions of surface convergence. Findings indicate that different species/stocks use different habitats. Some forage at or near the surface at convergences and others forage sub-surface away from currents (Polovina et al., 2002). References: Bonjean, F. and G.S.E. Lagerloef, 2002: Diagnostic model and analysis of the surface currents in the Tropical Pacific Ocean, J. Phys. Oceanogr., In press. Lagerloef,G.S.E., G.Mitchum, R.Lukas and P.Niiler, 1999: Tropical Pacific near sur- face currents estimated from altimeter, wind and drifter data, J. Geophys. Res., 104, 23,313-23,326. Polovina, J. J., G. H. Balazs, E. A Howell, D. M. Parker, M. P. Seki, and P. H. Dutton, 2002. Forage and migration habitat of loggerhead (Caretta caretta) and olive ridley (Lepidochelys olivacea) sea turtles in the central North Pacific Ocean. Fish. Oceanogr., In Review.

  1. Population genetics and phylogeography of sea turtles.

    PubMed

    Bowen, B W; Karl, S A

    2007-12-01

    The seven species of sea turtles occupy a diversity of niches, and have a history tracing back over 100 million years, yet all share basic life-history features, including exceptional navigation skills and periodic migrations from feeding to breeding habitats. Here, we review the biogeographic, behavioural, and ecological factors that shape the distribution of genetic diversity in sea turtles. Natal homing, wherein turtles return to their region of origin for mating and nesting, has been demonstrated with mtDNA sequences. These maternally inherited markers show strong population structure among nesting colonies while nuclear loci reveal a contrasting pattern of male-mediated gene flow, a phenomenon termed 'complex population structure'. Mixed-stock analyses indicate that multiple nesting colonies can contribute to feeding aggregates, such that exploitation of turtles in these habitats can reduce breeding populations across the region. The mtDNA data also demonstrate migrations across entire ocean basins, some of the longest movements of marine vertebrates. Multiple paternity occurs at reported rates of 0-100%, and can vary by as much as 9-100% within species. Hybridization in almost every combination among members of the Cheloniidae has been documented but the frequency and ultimate ramifications of hybridization are not clear. The global phylogeography of sea turtles reveals a gradient based on habitat preference and thermal regime. The cold-tolerant leatherback turtle (Dermochelys coriacea) shows no evolutionary partitions between Indo-Pacific and Atlantic populations, while the tropical green (Chelonia mydas), hawksbill (Eretmochelys imbricata), and ridleys (Lepidochelys olivacea vs. L. kempi) have ancient separations between oceans. Ridleys and loggerhead (Caretta caretta) also show more recent colonization between ocean basins, probably mediated by warm-water gyres that occasionally traverse the frigid upwelling zone in southern Africa. These rare events may

  2. Patterns and inferred processes associated with sea turtle strandings in Paraíba State, Northeast Brazil.

    PubMed

    Poli, C; Lopez, L C S; Mesquita, D O; Saska, C; Mascarenhas, R

    2014-05-01

    This study analysed sea turtle strandings on the coast of Paraíba State, Northeastern Brazil, from August 2009 to July 2010. A total of 124 strandings were recorded in this period: green turtle Chelonia mydas (n = 106), hawksbill Eretmochelys imbricata (n = 15), olive ridley Lepidochelys olivacea (n = 2) and loggerhead Caretta caretta (n = 1). Of all turtles for which the Curved Carapace Length (CCL) was measured (n = 122), only 12 individuals (9.7%) were adults. Twenty individuals had synthetic anthropogenic debris in the gastrointestinal tract. Other traces of human interactions were observed in 43 individuals, such as injuries caused by entanglement in fishing lines or nets, collisions with vessels, direct contact with oil spills and lesions caused by sharp or spiked objects. Moreover, in 28.5% of the stranded turtles, the presence of external tumors was noticed, suggestive of fibropapillomatosis and in 9.7%, shark bite marks were observed. Of the 107 individuals that were sexed, 76 were females and 31 were males. Most turtles (72.6%) became stranded during the spring/summer (between October and March). We found evidence of human interactions (injuries) in half of the strandings, but in most cases it was not possible to determine if such interactions were the cause of death. A logistic regression found a significant relationship between CCL, ingestion of debris and lesions caused by sharks or spiked objects. Systematic data collection from stranded sea turtles can provide useful biological information, such as seasonal and spatial patterns in their occurrence and mortality, age structure, sex ratio and diet, as well as possible mortality causes.

  3. Isolation, characterization, and antibiotic resistance of Vibrio spp. in sea turtles from Northwestern Mexico.

    PubMed

    Zavala-Norzagaray, Alan A; Aguirre, A Alonso; Velazquez-Roman, Jorge; Flores-Villaseñor, Héctor; León-Sicairos, Nidia; Ley-Quiñonez, C P; Hernández-Díaz, Lucio De Jesús; Canizalez-Roman, Adrian

    2015-01-01

    The aerobic oral and cloacal bacterial microbiota and their antimicrobial resistance were characterized for 64 apparently healthy sea turtles captured at their foraging grounds in Ojo de Liebre Lagoon (OLL), Baja California Sur (BCS), Mexico (Pacific Ocean) and the lagoon system of Navachiste (LSN) and Marine Area of Influence (MAI), Guasave, Sinaloa (Gulf of California). A total of 34 black turtles (Chelonia mydas agassizii) were sampled in OLL and eight black turtles and 22 olive ridley turtles (Lepidochelys olivacea) were sampled in LSN and MAI, respectively from January to December 2012. We isolated 13 different species of Gram-negative bacteria. The most frequently isolated bacteria were Vibrio alginolyticus in 39/64 (60%), V. parahaemolyticus in 17/64 (26%), and V. cholerae in 6/64 (9%). However, V. cholerae was isolated only from turtles captured from the Gulf of California (MAI). Among V. parahaemolyticus strains, six O serogroups and eight serovars were identified from which 5/17 (29.4%) belonged to the pathogenic strains (tdh (+) gene) and 2/17 (11.7%) had the pandemic clone (tdh (+) and toxRS/new (+)). Among V. cholerae strains, all were identified as non-O1/non-O139, and in 4/6 (66%) the accessory cholera enterotoxin gene (ace) was identified but without virulence gene zot, ctxA, and ctxB. Of the isolated V. parahaemolyticus, V. cholerae, and V. alginolyticus strains, 94.1, 33.4, and 100% demonstrated resistance to at least one commonly prescribed antibiotic (primarily to ampicillin), respectively. In conclusion, the presence of several potential (toxigenic) human pathogens in sea turtles may represent transmission of environmental microbes and a high-risk of food-borne disease. Therefore, based on the fact that it is illegal and unhealthy, we discourage the consumption of sea turtle meat or eggs in northwestern Mexico.

  4. A Bayesian model for assessing the frequency of multiple mating in nature.

    PubMed

    Neff, B D; Pitcher, T E; Repka, J

    2002-01-01

    Many breeding systems have multiple mating, in which males or females mate with multiple partners. With the advent of molecular markers, it is now possible to detect multiple mating in nature. However, no model yet exists to effectively assess the frequency of multiple mating (f(mm))--the proportion of broods with at least two males (or females) genetically contributing--from limited genetic data. We present a single-sex model based on Bayes' rule that incorporates the numbers of loci, alleles, offspring, and genetic parents. Two genetic criteria for calculating f(mm) are considered: the proportion of broods with three or more paternal (or maternal) alleles at any one locus and the total number of haplotypes observed in each brood. The former criterion provides the most precise estimates of f(mm). The model enables the calculation of confidence intervals and allows mutations (or typing errors) to be incorporated into the calculation. Failure to account for mutations can result in overestimates of f(mm). The model can also utilize other biological data, such as behavioral observations during mating, thereby increasing the accuracy of the calculation as compared to previous models. For example, when two sires contribute equally to multiply mated broods, only three loci with five equally common alleles are required to provide estimates of f(mm) with high precision. We demonstrate the model with an example addressing the frequency of multiple paternity in small versus large clutches of the endangered Kemp's Ridley sea turtle (Lepidochelys kempi) and show that females that lay large clutches are more likely to have multiply mated.

  5. Isolation, characterization, and antibiotic resistance of Vibrio spp. in sea turtles from Northwestern Mexico

    PubMed Central

    Zavala-Norzagaray, Alan A.; Aguirre, A. Alonso; Velazquez-Roman, Jorge; Flores-Villaseñor, Héctor; León-Sicairos, Nidia; Ley-Quiñonez, C. P.; Hernández-Díaz, Lucio De Jesús; Canizalez-Roman, Adrian

    2015-01-01

    The aerobic oral and cloacal bacterial microbiota and their antimicrobial resistance were characterized for 64 apparently healthy sea turtles captured at their foraging grounds in Ojo de Liebre Lagoon (OLL), Baja California Sur (BCS), Mexico (Pacific Ocean) and the lagoon system of Navachiste (LSN) and Marine Area of Influence (MAI), Guasave, Sinaloa (Gulf of California). A total of 34 black turtles (Chelonia mydas agassizii) were sampled in OLL and eight black turtles and 22 olive ridley turtles (Lepidochelys olivacea) were sampled in LSN and MAI, respectively from January to December 2012. We isolated 13 different species of Gram-negative bacteria. The most frequently isolated bacteria were Vibrio alginolyticus in 39/64 (60%), V. parahaemolyticus in 17/64 (26%), and V. cholerae in 6/64 (9%). However, V. cholerae was isolated only from turtles captured from the Gulf of California (MAI). Among V. parahaemolyticus strains, six O serogroups and eight serovars were identified from which 5/17 (29.4%) belonged to the pathogenic strains (tdh+ gene) and 2/17 (11.7%) had the pandemic clone (tdh+ and toxRS/new+). Among V. cholerae strains, all were identified as non-O1/non-O139, and in 4/6 (66%) the accessory cholera enterotoxin gene (ace) was identified but without virulence gene zot, ctxA, and ctxB. Of the isolated V. parahaemolyticus, V. cholerae, and V. alginolyticus strains, 94.1, 33.4, and 100% demonstrated resistance to at least one commonly prescribed antibiotic (primarily to ampicillin), respectively. In conclusion, the presence of several potential (toxigenic) human pathogens in sea turtles may represent transmission of environmental microbes and a high-risk of food-borne disease. Therefore, based on the fact that it is illegal and unhealthy, we discourage the consumption of sea turtle meat or eggs in northwestern Mexico. PMID:26161078

  6. Incorporating uncertainty of management costs in sensitivity analyses of matrix population models.

    PubMed

    Salomon, Yacov; McCarthy, Michael A; Taylor, Peter; Wintle, Brendan A

    2013-02-01

    The importance of accounting for economic costs when making environmental-management decisions subject to resource constraints has been increasingly recognized in recent years. In contrast, uncertainty associated with such costs has often been ignored. We developed a method, on the basis of economic theory, that accounts for the uncertainty in population-management decisions. We considered the case where, rather than taking fixed values, model parameters are random variables that represent the situation when parameters are not precisely known. Hence, the outcome is not precisely known either. Instead of maximizing the expected outcome, we maximized the probability of obtaining an outcome above a threshold of acceptability. We derived explicit analytical expressions for the optimal allocation and its associated probability, as a function of the threshold of acceptability, where the model parameters were distributed according to normal and uniform distributions. To illustrate our approach we revisited a previous study that incorporated cost-efficiency analyses in management decisions that were based on perturbation analyses of matrix population models. Incorporating derivations from this study into our framework, we extended the model to address potential uncertainties. We then applied these results to 2 case studies: management of a Koala (Phascolarctos cinereus) population and conservation of an olive ridley sea turtle (Lepidochelys olivacea) population. For low aspirations, that is, when the threshold of acceptability is relatively low, the optimal strategy was obtained by diversifying the allocation of funds. Conversely, for high aspirations, the budget was directed toward management actions with the highest potential effect on the population. The exact optimal allocation was sensitive to the choice of uncertainty model. Our results highlight the importance of accounting for uncertainty when making decisions and suggest that more effort should be placed on

  7. Two new species of the genus Vosmaeropsis Dendy, 1892 (Porifera, Calcarea), with comments on the distribution of V. sericata (Ridley, 1881) along the Southwestern Atlantic Ocean.

    PubMed

    Cavalcanti, Fernanda F; Bastos, Nilma; Lanna, Emilio

    2015-05-12

    Two new species of the genus Vosmaeropsis are described: V. recruta sp. nov. and V. complanatispinifera sp. nov., both from the Brazilian coast. These species possess arrow-shaped large diactines in their skeletons, which are being described for the first time in Vosmaeropsis. In addition, the latter species presents another remarkable character: the apical actines of its atrial tetractines is flattened and provided with spines. Vosmaeropsis complanastispinifera sp. nov. is being proposed based on the re-analysis of specimens that in the past were assigned to V. sericata. Thus, with the reallocation of these specimens to the newly described species, the current distribution range of V. sericata does not include the Brazilian northeastern coast. Vosmaeropsis now comprises 23 species. Most of them present an endemic pattern of distribution, but the genus is widely distributed in tropical and temperate regions around the world.

  8. Helminths from an introduced species (Tupinambis merianae), and two endemic species (Trachylepis atlantica and Amphisbaena ridley) from Fernando de Noronha Archipelago, Brazil.

    PubMed

    Ramalho, A C O; da Silva, R J; Schwartz, H O; Péres, A K

    2009-08-01

    The present study reports the occurrence of helminths in the introduced species Tupinambis merianae (tegu lizard), and in two endemic species Trachylepis atlantica (small lizard) and Amphisbaena ridleyi (two-head-snake lizard ), from Fernando de Noronha Archipelago, State of Pernambuco, Brazil. Nine species of helminths were found, mainly in the digestive tract and accessory organs, with the following prevalence (P) and mean infection intensity (MII). Tupinambis merianae: Diaphanocephalus galeatus (P = 96%, MII = 20.5), Spinicauda spinicauda (P = 100%, MII = 197.8), and Oochoristica sp.l (P = 20%, MII = 4.4). Trachylepis atlantica: Moaciria alvarengai (P = 20%, MII = 1.4), S. spinicauda (P = 92%, MII = 22.1), Mesocoelium monas (P = 4%, MII = 3.0), Platynosomum sp. (P = 8%, MII = 7.0), and Oochoristica sp.2 (P = 16%, MII = 1.25). Amphisbaena ridleyi: Aplectana albae (P = 96%, MII = 143.4), Thelandros alvarengai (P = 4%, MII = 1.0), Me. monas (P = 44%, MII = 2.8), Platynosomum sp. (P = 36%; MII = 13.8), and Oochoristica sp.2 (P = 48%; MII = 2.17). More than 80% of T. merianae were infected with 2, or more, helminth species. In Tr. atlantica, single-species infections were present in 50% of the specimens, but co-occurrence of 2 parasites was also high (41.7%). In A. ridleyi, multiple infections were more common, with up to 5 parasite species present. The helminth fauna observed allowed us to conclude that helminths can be carried together with their host when they colonize new geographic localities and that these introduced helminths can, in turn, colonize endemic, or native, hosts.

  9. The Community-based Whole Magnetosphere Model

    DTIC Science & Technology

    2011-11-15

    Ground magnetic field perturbations, Space Weather, 9, S02004, doi:10.1029/2010SW000600, 2011. 8 . Yiğit, E., A.J. Ridley, Effects of high- latitude...doi:10.1029/2009JA014596, 2010. 17. Welling, D. T., and A. J. Ridley, Vali- dation of SWMF magnetic field and plasma, Space Weather, 8 , S03002, doi... interplanetary magnetic fields , Ann. Geophys., 25, 533, 2007. CWMM-17 Ridley CWMM Final Report 45. A.J. Ridley, Effects of seasonal changes in the ionospheric

  10. 77 FR 54566 - Endangered Species; File No. 16134

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-05

    ... (Dermochelys coriacea), and loggerhead (Caretta caretta) sea turtles for purposes of scientific research... Kemp's ridley sea turtles in mid- Atlantic waters from North Carolina to New Jersey. The purposes of the research are to: (1) Update current knowledge of loggerhead and Kemp's ridley sea turtle...

  11. Young "Science Ambassadors" Raise the Profile of Science

    ERIC Educational Resources Information Center

    Ridley, Katie

    2014-01-01

    Katie Ridley, science coordinator at St. Gregory's Catholic Primary School, Liverpool, UK, states that the inspiration for "science ambassadors" came after embarking on the Primary Science Quality Mark programme at their school. Ridley realized that science was just not recognised as such by the children, they talked about scientific…

  12. Time Keeps on Ticking: The Experience of Clinical Judgment

    ERIC Educational Resources Information Center

    Spengler, Paul M.; White, Michael J.; Aegisdottir, Stefania; Maugherman, Alan S.

    2009-01-01

    The reactions by Ridley and Shaw-Ridley (EJ832451) and Lichtenberg (EJ832452) to the authors' meta-analysis on the effects of experience on judgment accuracy add positively to what is hoped will become an ever more focused discourse on this most basic question: How can mental health clinical decision making be improved? In this rejoinder, the…

  13. Learning to Integrate

    ERIC Educational Resources Information Center

    Osman, Tom

    2004-01-01

    Allan Ridley has many interesting qualities, not least his determination. Though he is totally blind, he doesn't let that stop him pursuing his interests, whether he is water skiing or learning database design. When asked to tutor blind learner Allan Ridley, the author had to give a lot of thought to making the curriculum accessible. This article…

  14. 76 FR 37327 - Endangered Species; File No. 16253

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-27

    ... turtles for scientific research. DATES: Written, telefaxed, or e-mail comments must be received on or..., loggerhead, green, hawksbill, olive ridley, and Kemp's ridley sea turtles in the Atlantic Ocean, Gulf of... commercial fishing gear to mitigate sea turtle interactions and capture under two projects, Project A...

  15. Shopping for Old and New Wine: A Response

    ERIC Educational Resources Information Center

    Murdock, Nancy L.; Nilsson, Johanna E.; Duan, Changming

    2012-01-01

    With this rejoinder, we address some of the concerns and questions raised by Ridley and Mollen (2012) and Hill (2012). Specially, we reflect upon Ridley and Mollen's commentary about whether the three theories in this major contribution can be deemed emergent or whether they are simply old thought in new packages. We also address Hill's question…

  16. Multicultural Approaches in Psychotherapy: A Rejoinder

    ERIC Educational Resources Information Center

    Owen, Jesse; Leach, Mark M.; Wampold, Bruce; Rodolfa, Emil

    2011-01-01

    In this rejoinder, the authors address several issues raised by R. L. Worthington and F. R. Dillon (2011) and C. R. Ridley and M. Shaw-Ridley (2011) regarding (a) the measurement of multicultural competencies (MCCs), (b) sampling considerations in multicultural research, and (c) the conceptual frame of multicultural psychotherapy research. The…

  17. Nanocomposite Interphases for Improved Transparent Polymer Composite Materials

    DTIC Science & Technology

    2008-08-01

    Nanocomposite Interphases for Improved Transparent Polymer Composite Materials by Daniel J. O’Brien, Jason Robinette, James R. Heflin , and...Jason Robinette Weapons and Materials Research Directorate, ARL James R. Heflin and Jason Ridley Virginia Polytechnic Institue and State... Heflin ,* and Jason Ridley* 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army Research Laboratory ATTN: AMSRD-ARL

  18. Intestinal helminths in immigrants in Naples (Italy): a comparison between two different diagnostic techniques

    PubMed Central

    Esposito, Silvano; Noviello, Silvana; Leone, Sebastiano; Pascale, Renato; Russo, Enrico; Gualdieri, Luciano

    2013-01-01

    Objective To compare two different methods for detection of intestinal parasitic in immigrants from high risk geographic areas for intestinal parasitic diseases. Methods A total of 307 stool specimens were analysed by Ridley method and FLOTAC, a new technique performing a direct count of all parasitic elements. Results : Compared to Ridley method, FLOTAC technique led to fewer negative results (P<0.05), index of a higher sensibility. Conclusions Performing a more accurate detection of parasites appears a goal to reach in terms of public health.

  19. A Decision Optimising Technique for Planners

    ERIC Educational Resources Information Center

    Openshaw, Stan; Whitehead, Paddy

    1975-01-01

    Draws attention to an existing methodology for handling decision-making in a typical planning situation of interrelated alternatives and data deficiency, and describes several important extensions that have recently been made to it. (Oriel Press Limited, 32 Ridley Place, Newcastle upon Tyne, NE1 8LH, Great Britain, $7.00 yearly.) (Author)

  20. [Book review] Fish and fishes of Saint Helena Island, by Alasdair J. Edwards

    USGS Publications Warehouse

    Smith-Vaniz, W.F.

    1991-01-01

    Review of: FISH AND FISHERIES OF SAINT HELENA ISLAND. By AlasdairJ. Edwards. 1990. Available from the author, Department of Biology, Ridley Building, University of Newcastle upon Tyne, NE1 7RU, England, 152 p., 24 p. color plates, £14.50 (or US$25.) surface, £17.00 (or US$30.)

  1. 75 FR 33578 - Endangered Species; File Nos. 14508 and 14655

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-14

    ... Ave South, St. Petersburg, FL 33701; phone (727) 824-5312; fax (727) 824-5309. FOR FURTHER INFORMATION... abundance, genetic origin and feeding ecology of sea turtles using Lake Worth Lagoon in Palm Beach County, Florida. Up to 50 green, 5 loggerhead, 2 hawksbill, and 1 Kemp's ridley sea turtles may be...

  2. Photo Surfing in Blade Runner

    ERIC Educational Resources Information Center

    Ohler, Jason

    2005-01-01

    This month's "Mining Movies" looks at Blade Runner, Ridley Scott's film set in the year 2019. It is a sad time for Earth, which is in the midst of environmental degradation so severe that other planets are being prepared for colonization. The main source of labor for this preparation work are "replicants," organic robots that look and behave like…

  3. Parenting the Gifted: The Ongoing Riddle of Which Nurture is Best for What Nature: Parents Promoting Gifted Potential

    ERIC Educational Resources Information Center

    Haensly, Patricia

    2004-01-01

    Matt Ridley, an Oxford-trained zoologist and science writer whose latest book is "Nature via Nurture: Genes, Experience, and What Makes Us Human" (2003a), wrote such an impressively clear and fascinating piece on "What Makes You Who You Are" that the author decided to use it to introduce the continuing pursuit of "What do I do to best promote…

  4. Decline of the Sea Turtles: Causes and Prevention.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Commission on Life Sciences.

    A report submitted by the Committee on Sea Turtle Conservation, addresses threats to the world's sea turtle populations to fulfill a mandate of the Endangered Species Act Amendments of 1988. It presents information on the populations, biology, ecology, and behavior of five endangered or threatened turtle species: the Kemp's ridley, loggerhead,…

  5. 75 FR 61133 - Marine Mammals and Endangered Species; File Nos. 808-1735, 14233, 14506, 14603, and 14726

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-04

    ... amendment to conduct research ] on marine mammals or sea turtles. See SUPPLEMENTARY INFORMATION for... leatherback (Dermochelys coriacea) sea turtles had been submitted by Llewellyn Ehrhart, Ph.D. [File No. 14506... research on green, hawksbill, Kemp's ridley, loggerhead, and leatherback sea turtles had been submitted...

  6. Learning from Experience: A Report from Mexico's Turtle Trip 2000.

    ERIC Educational Resources Information Center

    Jankowska, Marta Maja

    2000-01-01

    Fifteen high school students and adults from Idaho traveled to Mexico to assist the One World Workforce with monitoring the nests of olive ridley sea turtles. Only 1 percent of these endangered turtles mature to adulthood. The volunteers protected the eggs from poachers and helped the hatchlings get safely to the water. (TD)

  7. 78 FR 39258 - Endangered Species; File No. 18069

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-01

    ...), loggerhead (Caretta caretta), green (Chelonia mydas), and hawksbill (Eretmochelys imbricata) sea turtles for... to 100 Kemp's ridley, 20 green, 30 loggerhead, and five hawksbill sea turtles annually by strike net... migrations, movements, home range, and habitat associations. Dated: June 25, 2013. P. Michael Payne,...

  8. IPV among Adolescent Reproductive Health Patients: The Role of Relationship Communication

    ERIC Educational Resources Information Center

    Messinger, Adam M.; Davidson, Leslie L.; Rickert, Vaughn I.

    2011-01-01

    Population-specific data on factors that affect intimate partner violence (IPV) are needed on female adolescents and young adults, a cohort at greatest risk of IPV in the United States (Rennison, 2001). Studies have frequently overlooked the role of relationship communication as a gatekeeper to IPV (Ridley & Feldman, 2003). To address this…

  9. Introduction to the Special Section on Genomics

    ERIC Educational Resources Information Center

    Grigorenko, Elena L.; Dozier, Mary

    2013-01-01

    The debate about the relevance of human genetics knowledge to everyday life has been marked by fluctuations of interest and enthusiasm. The negative impact of eugenics on the public consciousness suppressed dialogue between geneticists and the public for most of the second half of the 20th century (Ridley, 1999). For the most part, nongeneticists…

  10. 75 FR 35834 - Receipt of Applications for Endangered Species Permits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-23

    ... receive Key deer (Odocoileus virginianus clavium) for veterinary treatment and rehabilitation. Applicant... to house for greater than 45 days, and provide care for and public education about, Key deer in Duval... in Alabama for Alabama beach mouse, Perdido Key beach mouse, Kemp's Ridley sea turtle, Alabama...

  11. Key members of the XS-1 Research Team

    NASA Technical Reports Server (NTRS)

    1948-01-01

    NACA Muroc Flight Test Unit XS-1 Team members and USAF Pilots. From Left to Right: Joseph Vensel, Head of Operations; Gerald Truszynski, Head of Instrumentation; Captain Charles Chuck Yeager, USAF pilot; Walter Williams, Head of the Unit; Major Jack Ridley, USAF pilot; and De E. Beeler, Head of Engineers.

  12. Key members of the XS-1 research team

    NASA Technical Reports Server (NTRS)

    1948-01-01

    NACA Muroc Flight Test Unit XS-1 Team members and USAF Pilots.From Left to Right: Joseph Vensel, Head of Operations; Gerald Truszynski, Head of Instrumentation; Captain Charles 'Chuck' Yeager, USAF pilot; Walter Williams, Head of the Unit; Major Jack Ridley, USAF pilot; and De E. Beeler, Head of Engineers.(1947)

  13. A Positive Psychology That Matters

    ERIC Educational Resources Information Center

    Lopez, Shane L.; Magyar-Moe, Jeana L.

    2006-01-01

    The Major Contribution intended to situate positive psychology in counseling psychology's past and future and in the complex world we live and work in today. The four reactions (Frazier, Lee,& Steger; Gerstein; Linley; Mollen, Ethington,& Ridley) provide new insights into how counseling psychology has and will contribute to the study of human…

  14. Measurement of Peroxyacetyl Nitrate (PAN), Peroxypropionyl Nitrate (PPN) and Peroxymethacryloyl Nitrate (MPAN) during TRACE-P

    NASA Technical Reports Server (NTRS)

    Flocke, Frank; Weinheimer, Andrew J.

    2003-01-01

    In Fall 2000, the PANs gas chromatograph (GC) was improved and prepared for installation on the NASA P-3. A number of experiments were conducted in conjunction with the NCAR NO,, instrument (B. Ridley) to settle some of the fine details of the output of the calibration system for each instrument. In addition, the sampling frequency was improved.

  15. Environmental Assessment of Building Demolition at Test Area A-15 (RCS 98-571, 98-572, 98-573, 00-522, 00-523, and 00-731)

    DTIC Science & Technology

    2004-02-01

    Turtles Green sea turtle Chelonia mydas Endangered* Endangered Hawksbill sea turtle Eretmochelys imbricata Endangered Endangered Kemp’s ridley...green turtle ( Chelonia mydas ), typically nest during the months from May through August with hatching occurring from late July through October

  16. Multicultural approaches in psychotherapy: A rejoinder.

    PubMed

    Owen, Jesse; Leach, Mark M; Wampold, Bruce; Rodolfa, Emil

    2010-12-20

    In this rejoinder, the authors address several issues raised by R. L. Worthington and F. R. Dillon (2011) and C. R. Ridley and M. Shaw-Ridley (2011) regarding (a) the measurement of multicultural competencies (MCCs), (b) sampling considerations in multicultural research, and (c) the conceptual frame of multicultural psychotherapy research. The authors challenge the wisdom of exploring MCCs in psychotherapy research and provide a different framework to understand therapists' multicultural effectiveness with clients based on their cultural race/ethnicity. Additionally, the concept of therapists' multicultural orientation or approach is introduced to illuminate the process of aligning with clients about salient cultural issues in psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  17. Results from the chemical analysis of oily residue samples taken from stranded juvenile sea turtles collected from Padre and Mustang Islands, Texas. Special report (Final)

    SciTech Connect

    Overton, E.B.; Byrne, C.J.; McFall, J.A.; Antoine, S.R.; Laseter, J.L.

    1983-12-01

    Juvenile Kemp's Ridley sea turtles were released June 7, 1983 off the Texas coast by the National Marine Fisheries Service, as part of an U.S. - Mexico cooperative effort to augment the natural breeding stock of the endangered species. Between one and six days later many dead or distressed Kemp's Ridleys were found stranded on Padre and Mustang Islands with oily residues in the mouth and esophagus. Six samples were analyzed for Ni/V content API gravity, stable C, H, and S isotopes, and hydrocarbon composition with high-resolution gas chromatography and HRGC-mass spectrometry. Results were: (1) oils came from multiple sources, (2) composition was predominantly in the n-C20 to n-C32 range (waxy paraffins), (3) residues were most probably from discarded tanker cleaning operations.

  18. Energy Conversion in High Enthalpy Flows and Non-equilibrium Plasmas

    DTIC Science & Technology

    2014-01-01

    Igor V. Adamovich5, Walter R. Lempert6, and J. William Rich*7 Michael A. Chaszeyka Nonequilibrium Thermodynamics Laboratories, Department of...Uribarri and Ned Allen); and The Michael A. Chaszeyka Gift to the OSU Nonequilibrium Thermodynamics Laboratories. We wish to thank Dr. Graham Candler and...Burks, T.L., and Lin, M.C., Chemical Physics, vol. 44, 1979, pp. 143-150 44. Hancock, G., Ridley, B.A., Smith, I.W.M., J. Chem. Soc. Faraday Trans. 2

  19. Environmental Impact Research Program. Life History and Environmental Requirements of Loggerhead Sea Turtles.

    DTIC Science & Technology

    1986-01-01

    and nests are raccoons, crabs, and hogs. Hatchlings are taken by mamals , birds, and crabs as they emerge from the nest and crawl to the water. The...greatest predation is likely to be by nearshore fish after the hatchlings reach the water. Because of their size, predation on Juvenile and adult sea...When they crawl ashore to nest, loggerheads, like hawksbills and Kemp’s ridleys, dig a shallow pit for their body (Fig- ure 5) and then dig a flask

  20. Life History and Environmental Requirements of Loggerhead Turtles

    DTIC Science & Technology

    1988-08-01

    Figure 4) (Pritchard et al. 1983). When they crawl ashore to nest, loggerheads, like hawksbills and Mating Kemp’s ridleys, dig a shallow pit for their...thousand is likely turtles have not been studied, logger- to survive that long) (Frazer 1983c). heads in laboratory experiments had From tag return data, a...1982). The greatest predation on hatchlings is Observations in Australia suggest likely to occur after they reach the that local availability of

  1. Sample Fabrication and Experimental Approach for Studying Interfacial Sliding in Thin Film-Substrate Systems

    DTIC Science & Technology

    2006-09-01

    Technology 14.5 (1998): 405-410. 19. Zuruzi, A. S., H. Li, and G. Dong. "Diffusion Bonding of Aluminium Alloy 6061 in Air Using an Interface...428. 18. Huang, Y., F. J. Humphreys, N. Ridley, and Z. C. Wang. "Diffusion Bonding of Hot Rolled 7075 Aluminium Alloy." Materials Science and...and Takashi Ohnishi. "Effect of Aluminium Oxide Caps on Hillock Formation in Aluminium Alloy Films." Thin Solid Films 349 (1999): 191-198. 53

  2. Efficient Multi-Source Data Fusion for Decentralized Sensor Networks

    DTIC Science & Technology

    2006-10-01

    Information Fusion, 7-10 August 2001, Montreal, Canada. [2] E. Nettleton , “Decentralised Architectures for Tracking and Navigation with Multiple Flight...Proceedings of the 5th International Conference on Information Fusion, 8-11 July 2002, Annapolis, MD. [16] M. Ridley, E Nettleton , S. Sukkarieh and H...Decentralized Sensing Networks,” Proceedings of the 4th International Conference on Information Fusion, 7-10 August 2001, Montreal, Canada. [2] E. Nettleton

  3. Intraocular lens providing good vision 23 years after placement.

    PubMed Central

    Gillan, J. G.

    1977-01-01

    A Ridley Perspex lens was placed in the posterior chamber of a man's eye 23 years ago; 20/25 vision has been maintained since. This technique, first carried out in 1949, has been abandoned because of the high incidence of lens dislocation and glaucoma, but many modified versions of the lens have been produced. Implantation of intraocular lenses is still considered experimental, though careful selection of cases and meticulous surgical procedure can yield good results. PMID:608150

  4. Three closely related herpesviruses are associated with fibropapillomatosis in marine turtles

    USGS Publications Warehouse

    Quackenbush, S.L.; Work, T.M.; Balazs, G.H.; Casey, R.N.; Rovnak, J.; Chaves, A.; duToit, L.; Baines, J.D.; Parrish, C.R.; Bowser, P.R.; Casey, J.W.

    1998-01-01

    Green turtle fibropapillomatosis is a neoplastic disease of increasingly significant threat to the survivability of this species. Degenerate PCR primers that target highly conserved regions of genes encoding herpesvirus DNA polymerases were used to amplify a DNA sequence from fibropapillomas and fibromas from Hawaiian and Florida green turtles. All of the tumors tested (n= 23) were found to harbor viral DNA, whereas no viral DNA was detected in skin biopsies from tumor-negative turtles. The tissue distribution of the green turtle herpesvirus appears to be generally limited to tumors where viral DNA was found to accumulate at approximately two to five copies per cell and is occasionally detected, only by PCR, in some tissues normally associated with tumor development. In addition, herpesviral DNA was detected in fibropapillomas from two loggerhead and four olive ridley turtles. Nucleotide sequencing of a 483-bp fragment of the turtle herpesvirus DNA polymerase gene determined that the Florida green turtle and loggerhead turtle sequences are identical and differ from the Hawaiian green turtle sequence by five nucleotide changes, which results in two amino acid substitutions. The olive ridley sequence differs from the Florida and Hawaiian green turtle sequences by 15 and 16 nucleotide changes, respectively, resulting in four amino acid substitutions, three of which are unique to the olive ridley sequence. Our data suggest that these closely related turtle herpesviruses are intimately involved in the genesis of fibropapillomatosis.

  5. Why some Jehovah's Witnesses accept blood and conscientiously reject official Watchtower Society blood policy

    PubMed Central

    Elder, L.

    2000-01-01

    In their responses to Dr Osamu Muramoto (hereafter Muramoto) Watchtower Society (hereafter WTS) spokesmen David Malyon and Donald Ridley (hereafter Malyon and Ridley),1–3 deny many of the criticisms levelled against the WTS by Muramoto.4–6 In this paper I argue as a Jehovah's Witness (hereafter JW) and on behalf of the members of AJWRB that there is no biblical basis for the WTS's partial ban on blood and that this dissenting theological view should be made clear to all JW patients who reject blood on religious grounds. Such patients should be guaranteed confidentiality should they accept whole blood or components that are banned by the WTS. I argue against Malyon's and Ridley's claim that WTS policy allows freedom of conscience to individual JWs and that it is non-coercive and non-punitive in dealing with conscientious dissent and I challenge the notion that there is monolithic support of the WTS blood policy among those who identify themselves as JWs and carry the WTS "advance directive". Key Words: Blood transfusion • Jehovah's Witnesses • Watchtower • autonomy PMID:11055042

  6. MBE Growth of CdTe and Hg sub 1-x Cd sub x Te Films and Multilayer Structures.

    DTIC Science & Technology

    2014-09-26

    K. Ridley, Solid State Electronics 27(2), 113 (1984). 3. R. F. C. Farrow, G. R. Jones, G. M. Williams, and 1. M. Young, AppI . Phys. Lett. 39, 954...R. F. C. Farrow, W. J. Takei, F. A. Shirland, and A. J. Noreika, J. AppI . Phys. 55(12), 4225 (1984). 8. G. M. Williams, C. R. Whitehouse, N. G. Chew... Appi . Phys. 55. 4225 (1984). The critical role of growth-related parameters including ’Z. C. Feng, A. Masicarenhas. W. J. Choyke. R. F. C. Farrow, F

  7. Robotic telescope observing with the BAA

    NASA Astrophysics Data System (ADS)

    Meadows, P.

    2010-06-01

    Have you ever wished you had access to a telescope that can image down to magnitude 20 from the comfort of your own home? This is now made possible by using the growing number of robotic telescopes around the world that are available for amateur astronomers to acquire such CCD imagery. In 2008, using income derived from the legacy of renowned BAA observer Harold Ridley, the Robotic Telescope Project was started to encourage members to contribute to the various BAA Observing Sections using robotic telescopes, by providing a 50% subsidy on commercial rates (up to a limit per member).

  8. Hot Electron Effects of Importance for Micron and Submicron Devices.

    DTIC Science & Technology

    1981-09-01

    AD-AI05 616 ILLINOIS UNIV AT URBANA COORDINATED SCIENCE LAB F/ B 20/5 HOT ELECTRON EFFECTS OF IMPORTANCE FOR MICRON AND SUBMICRON OEV--ETC(U) SEP BI K...transport in heterolayers which was also treated and partly expanded by B . K. Ridley and P. Price. 2. Transport at Extremely High Electric Fields and Impact...467-469 (19"’)). 4. M. Keever, H. Shichijo, K. Hess, !. P°n-"rje. L. Witkowsi, :. rko; and B . a. Streetman, Measurements of !f{? E].e"’-ron C

  9. Venus mesosphere and thermosphere. II - Global circulation, temperature, and density variations

    NASA Technical Reports Server (NTRS)

    Bougher, S. W.; Dickinson, R. E.; Ridley, E. C.; Roble, R. G.; Nagy, A. F.

    1986-01-01

    The Dickinson and Ridley (1977) symmetric, two-dimensional hydrodynamical model framework is presently used as the basis of a reexamination of the circulation and structure of the Venus thermosphere recently revealed by Pioneer Venus observations. The observed day-to-night variation of composition and temperatures can largely be derived by a wave-drag parameterization yielding a weaker circulation system than that predicted prior to Pioneer Venus. It is also suggested that eddy diffusion is a minor contributor to the maintenance of observed day and nightside densities, and that eddy coefficients are smaller than than those of one-dimensional composition models previously employed.

  10. The anharmonic phonon decay rate in group-III nitrides

    NASA Astrophysics Data System (ADS)

    Srivastava, G. P.

    2009-04-01

    Measured lifetimes of hot phonons in group-III nitrides have been explained theoretically by considering three-phonon anharmonic interaction processes. The basic ingredients of the theory include full phonon dispersion relations obtained from the application of an adiabatic bond charge model and crystal anharmonic potential within the isotropic elastic continuum model. The role of various decay routes, such as Klemens, Ridley, Vallée-Bogani and Barman-Srivastava channels, in determining the lifetimes of the Raman active zone-centre longitudinal optical (LO) modes in BN (zincblende structure) and A1(LO) modes in AlN, GaN and InN (wurtzite structure) has been quantified.

  11. [Mucocutaneous leishmaniasis. Histologic classification and anatomoclinical correlations. Apropos of 102 cases].

    PubMed

    Huaman, J A; Castillo, M C

    1990-01-01

    Two hundred and three skin and mucosal biopsies performed in 162 patients suffering from leishmaniasis, were studied retrospectively. They were classified according to Ridley into 5 histological groups of increasing severity. In cutaneous leishmaniasis, a high proportion of the biopsies belonged to groups III and IV. In mucocutaneous leishmaniasis, the percentage of groups III and VI was lower and group V was present in 20% of cases. In 16 patients, followed by repeated biopsies, we detected some variations of the histological group during the course of the disease. However, there were no positive correlations between clinicopathological features and prognosis.

  12. Rapid Diagnosis of Brugia malayi and Wuchereria bancrofti Filariasis by an Acridine Orange/Microhematocrit Tube Technique

    DTIC Science & Technology

    1990-01-01

    cyte monophenol oxida uviN in mos- thme laboratory biology and mai nance of-ti-des quitoescexposed to microfil ac ofiof’ aria mm. fri vilfofus. Mosquito...h aaie r detected in samples diluted to alevel ofappr-dmately 18;Rcmne l,18) h aaie r 50/mI. K \\/i )’c cl stained by the acridine orange dye and can...Ridley, Department of ratory Medicin, College of teninary Medicine; *Division of Biology and ji~epartment of Anatomy anid Phys , College of Veterinary

  13. National Program for Inspection of Non-Federal Dams. Pleasant Lake Dam (NH 00179), State Number 61.01, Merrimack River Basin, Deerfield, New Hampshire. Phase I Inspection Report.

    DTIC Science & Technology

    1978-07-01

    ton -ery Ia 0 I 4 as AAo 144; Milt.on lioo ilFD ~ 26 Mill M!. do Union 1621A re Hatch*, 1 Middleton, 2e Ridley Hill 760 ’ O Alton Bay Corners ConrND y...tion of the dam. The earthen embankment is believed to have been built in the late 1800’s. Suncook Mills is believed to have built the concrete...less than 10 lives and some property damage. e. Ownership. The present dam is believed to have been constructed in 1921 by Sincook Mills for use in

  14. Two-way self-consistent simulation of the inner magnetosphere driven by realistic electric and magnetic fields

    NASA Astrophysics Data System (ADS)

    Ilie, Raluca; Liemohn, Michael; Toth, Gabor

    2014-05-01

    The geomagnetic storm of August 6, 2011 is examined using the two-way self consistent coupling between the kinetic Hot Electron and Ion Drift Integrator (HEIDI) model, the Block Adaptive Tree Solar Wind Roes-Type Scheme (BATS-R-US) MHD model and the Ridley Ionospheric Model (RIM) through the Space Weather Modeling Framework (SWMF). HEIDI solves the time dependent, gyration and bounce-averaged kinetic equation for the phase space density of different ring current species and computes full pitch angle distributions for all local times and radial distances. This model was generalized to accommodate arbitrary magnetic fields and through the coupling with the SWMF it obtains magnetic field description along with plasma distribution at the model boundaries from the BATS-R-US model within the SWMF. Electric field self-consistency is assured by the passing of convection potentials from the Ridley Ionosphere Model (RIM) within SWMF. Our study tests the various levels of coupling between the three models, highlighting the role the magnetic field, plasma sheet conditions and the cross polar cap potential play in the formation and evolution of the ring current. We use the results of the coupled HEIDI, BATSRUS and RIM models during disturbed conditions to study the importance of a kinetic self-consistent approach to the description of geospace.

  15. Cape Adare - A sentinel for change in Antarctica

    NASA Astrophysics Data System (ADS)

    Wilson, G. S.; Cary, C.; Cummings, V.; Hawes, I.; Hong, S. G.; Coleman, M.

    2015-12-01

    Cape Adare stretches some 40km beyond the Antarctic Continent across the Continental Shelf. It is flanked to the east by the northern Ross Sea and to the West by Robertson Bay. The following characteristics make it an ideal monitoring and observation point to understand the impact of warm ocean and climate propogating into Antarctica from the Southern Ocean: 1) Robertson Bay is some 500m deep and has the potential to record deep water inflow which is predicted as climate warms and is also indicated as the biggest risk for melting Antarctic ice shelves. 2) Cape Adare also lies between the Antarctic continental high pressure and the Southern Ocean low pressure 3) Ridley Beach at the tip of the Peninsula is home to Antarctica's largest Adelie Penguin Colony In November 2015 we will conduct a pilot survey of the marine and terrestrial ecology and physical setting, with a view to determining what opportunities exist for a long term monitoring system. Cape Adare and the Ridley Beach Penguin Colony also offers the advantage of being on the edge of the proposed Ross Sea marine protected area and may represent an opportunity to monitor the associated ecosystem.

  16. Ionosphere-Thermosphere Coupling and Energy Partitioning During Two HSS Events

    NASA Astrophysics Data System (ADS)

    Verkhoglyadova, Olga; Mannucci, Anthony; Meng, Xing; Tsurutani, Bruce; Mlynczak, Martin; Hunt, Linda; Redmon, Robert; Green, Janet

    2015-04-01

    We analyze external driving of the ionosphere-thermosphere (IT) system during two CIR-HSS events, on 29 April - 4 May 2011 and on 8-12 May 2012. By studying similar CIR-HSS events in the same phase of a solar cycle and the same season we aim to understand differences and similarities in the magnetosphere-IT coupling caused by external driving and other factors (pre-conditioning or driving from below). We focus on understanding energy and momentum transfer (with solar wind coupling functions, Joule heating, nitric oxide (NO) infrared cooling radiation and energetic particle precipitation) and corresponding energy partitioning in the IT system. We utilize observations from DMSP, POES/MEPED and TIMED/SABER. We use the Global Ionosphere-Thermosphere Model (GITM, Ridley et al., 2006) with different driving inputs to understand the IT response. We outline a physics-based approach for forecasting moderate to intense storms in the Earth's upper atmosphere caused by solar wind disturbances. Ridley, A. J., Y. Deng, and G. Toth (2006), The global ionosphere-thermosphere model, Journal of Atmospheric and Solar-Terrestrial Physics, 68(8), 839-864, doi:10.1016/j.jastp.2006.01.008.

  17. Conservation hotspots for the turtles on the high seas of the Atlantic Ocean.

    PubMed

    Huang, Hsiang-Wen

    2015-01-01

    Understanding the distribution of bycaught sea turtles could inform conservation strategies and priorities. This research analyses the distribution of turtles caught as longline fisheries bycatch on the high seas of the Atlantic Ocean. This research collected 18,142 bycatch observations and 47.1 million hooks from large-scale Taiwanese longline vessels in the Atlantic Ocean from June 2002 to December 2013. The coverage rates were ranged from 0.48% to 17.54% by year. Seven hundred and sixty-seven turtles were caught, and the major species were leatherback (59.8%), olive ridley (27.1%) and loggerhead turtles (8.7%). Most olive ridley (81.7%) and loggerhead (82.1%) turtles were hooked, while the leatherbacks were both hooked (44.0%) and entangled (31.8%). Depending on the species, 21.4% to 57.7% were dead when brought onboard. Most of the turtles were caught in tropical areas, especially in the Gulf of Guinea (15°N-10°S, 30°W-10°E), but loggerheads were caught in the south Atlantic Ocean (25°S-35°S, 40°W-10°E and 30°S-40°S, 55°W-45°W). The bycatch rate was the highest at 0.030 per 1000 hooks for leatherbacks in the tropical area. The bycatch rates of olive ridley ranged from 0 to 0.010 per thousand hooks. The loggerhead bycatch rates were higher in the northern and southern Atlantic Ocean and ranged from 0.0128 to 0.0239 per thousand hooks. Due to the characteristics of the Taiwanese deep-set longline fleet, bycatch rates were lower than those of coastal longline fisheries, but mortality rates were higher because of the long hours of operation. Gear and bait modification should be considered to reduce sea turtle bycatch and increase survival rates while reducing the use of shallow hooks would also be helpful.

  18. Conservation Hotspots for the Turtles on the High Seas of the Atlantic Ocean

    PubMed Central

    Huang, Hsiang-Wen

    2015-01-01

    Understanding the distribution of bycaught sea turtles could inform conservation strategies and priorities. This research analyses the distribution of turtles caught as longline fisheries bycatch on the high seas of the Atlantic Ocean. This research collected 18,142 bycatch observations and 47.1 million hooks from large-scale Taiwanese longline vessels in the Atlantic Ocean from June 2002 to December 2013. The coverage rates were ranged from 0.48% to 17.54% by year. Seven hundred and sixty-seven turtles were caught, and the major species were leatherback (59.8%), olive ridley (27.1%) and loggerhead turtles (8.7%). Most olive ridley (81.7%) and loggerhead (82.1%) turtles were hooked, while the leatherbacks were both hooked (44.0%) and entangled (31.8%). Depending on the species, 21.4% to 57.7% were dead when brought onboard. Most of the turtles were caught in tropical areas, especially in the Gulf of Guinea (15°N-10°S, 30°W-10°E), but loggerheads were caught in the south Atlantic Ocean (25°S-35°S, 40°W-10°E and 30°S-40°S, 55°W-45°W). The bycatch rate was the highest at 0.030 per 1000 hooks for leatherbacks in the tropical area. The bycatch rates of olive ridley ranged from 0 to 0.010 per thousand hooks. The loggerhead bycatch rates were higher in the northern and southern Atlantic Ocean and ranged from 0.0128 to 0.0239 per thousand hooks. Due to the characteristics of the Taiwanese deep-set longline fleet, bycatch rates were lower than those of coastal longline fisheries, but mortality rates were higher because of the long hours of operation. Gear and bait modification should be considered to reduce sea turtle bycatch and increase survival rates while reducing the use of shallow hooks would also be helpful. PMID:26267796

  19. Black Hawk Down: Film Zwischen Reflektion und Konstruktion Gesellschaftlicher Wirklichkeit

    NASA Astrophysics Data System (ADS)

    Pötzsch, Holger

    2009-05-01

    BLACK HAWK DOWN: FILM BETWEEN THE REFLECTION AND CONSTRUCTION OF SOCIAL REALITY - In this article, Ridley Scott's film Black Hawk Down (USA 2001) is read in the context of contemporary theories concerning cultural memory (Jan and Aleida Assmann) and media culture (Douglas Kellner). It is argued that film (and representation in general) does not merely reflect a preceding reality; it also actively serves to construct it. It is shown how Scott's film privileges one particular perspective on an actual event and how this point of view is objectified and installed in the memory of Western media culture. What potential implications does an increased blurring of fact and fiction in the representation of war have? What are the consequences for political and pedagogical practice? What role can cultural studies play in these processes?

  20. Sponges of the family Axinellidae (Porifera: Demospongiae) in Indonesia.

    PubMed

    Alvarez, Belinda; Voogd, Nicole J De; Soest, Rob W M Van

    2016-07-13

    Nine species in five genera of the family Axinellidae, including three new species, Axinella badungensis sp. nov., A. balinensis sp. nov. and Phycopsis pesgalli sp. nov. are recorded from Indonesian waters within the limits of the Western Coral Triangle province. Descriptions and discussion of those species are presented here. Four new combinations, Phakettia arbora (Sim, Kim & Byeon, 1990) comb.nov., P. trachys (De Laubenfels, 1954) comb.nov., Echinoclathria retepora (Lendenfeld, 1887) comb.nov. and Amphimedon hispidula (Ridley, 1884) comb.nov. are also established here. The distributions of species previously described are here extended to the study area with the exception of Phakellia atypica which seems so far restricted to Indonesia.

  1. Clathria (Thalysias) (Poecilosclerida: Demospongiae: Porifera) from Brazil:
    New species and redescription of Clathria (Thalysias) basiarenacea (Boury-Esnault, 1973).

    PubMed

    Galindo, Helcy; Hooper, John N A; Pinheiro, Ulisses

    2014-10-30

    The subgenus Clathria (Thalysias) Duchassaing & Michelotti, 1864 has 97 valid species, of which 27 are recorded in the Atlantic Ocean. However, only three species are known from Brazil so far. Here we provide the redescription of Clathria (Thalysias) basiarenacea (Boury- Esnault, 1973), based on the discovery of new characters (additional category of auxiliary styles, and details of spicules), and describe a new species of Clathria (Thalysias) repens sp. nov., that differs from sister species in having a live orange color, a massively encrusting repent growth form with lamellate folds and anastomosed projections, and three categories of structural styles, of which the two auxiliary styles have microspined heads. We also invalidate the record of Clathria (Thalysias) procera (Ridley, 1884) for Brazil. 

  2. Vincenz Fukala (1847-1911): versatile surgeon and early historian of ophthalmology.

    PubMed

    Schmidt, Dieter; Grzybowski, Andrzej

    2011-01-01

    Vincenz Fukala is best known for his technique of discission and linear extraction of the lens in young, highly myopic eyes--the technique adopted by Harold Ridley in preparation for lens implantation in young patients. He was Polish and trained in Vienna under Karl Ferdinand. von Arlt. Fukala practiced first in Pilsen (1889-1894), but returned to Vienna in 1895. He studied trachoma in Egypt in 1872. His research on scrofulous eye disease led him twice to the United States, in 1891 and 1892. Fukala also developed highly successful, pioneering techniques for the treatment of ectropion in blepharitis, of trachoma, and of shallow sockets following enucleation. In glaucoma, he recommended early iridectomy of the fellow eye when the first eye has gone blind. He was also an expert on the history of ancient European texts and of Arabic ophthalmology.

  3. Explosives remain preferred methods for platform abandonment

    SciTech Connect

    Pulsipher, A.; Daniel, W. IV; Kiesler, J.E.; Mackey, V. III

    1996-05-06

    Economics and safety concerns indicate that methods involving explosives remain the most practical and cost-effective means for abandoning oil and gas structures in the Gulf of Mexico. A decade has passed since 51 dead sea turtles, many endangered Kemp`s Ridleys, washed ashore on the Texas coast shortly after explosives helped remove several offshore platforms. Although no relationship between the explosions and the dead turtles was ever established, in response to widespread public concern, the US Minerals Management Service (MMS) and National Marine Fisheries Service (NMFS) implemented regulations limiting the size and timing of explosive charges. Also, more importantly, they required that operators pay for observers to survey waters surrounding platforms scheduled for removal for 48 hr before any detonations. If observers spot sea turtles or marine mammals within the danger zone, the platform abandonment is delayed until the turtles leave or are removed. However, concern about the effects of explosives on marine life remains.

  4. Underwater sightings of sea turtles in the northern Gulf of Mexico. Final report

    SciTech Connect

    Rosman, I.; Boland, G.S.; Martin, L.; Chandler, C.

    1987-10-01

    Between 1975 and 1985, eight scientific studies were conducted in the northern Gulf of Mexico. The purpose here was to review the data collected from all eight studies for information concerning underwater sightings of sea turtles. Records of 1,024 scuba dives, 909 hours of underwater video and submersible observations, and some 1,500 days of time-lapse photographic observations were compiled from published reports, data logs, and photographic material. The effort yielded 268 verifiable underwater sightings of sea turtles, 231 of which came from time-lapse cameras. The majority of sightings that could be identified by species were of loggerheads. Other species sighted included three leatherbacks and one Kemp's Ridley.

  5. Math anxiety: A review of its cognitive consequences, psychophysiological correlates, and brain bases.

    PubMed

    Suárez-Pellicioni, Macarena; Núñez-Peña, María Isabel; Colomé, Àngels

    2016-02-01

    A decade has passed since the last published review of math anxiety, which was carried out by Ashcraft and Ridley (2005). Given the considerable interest aroused by this topic in recent years and the growing number of publications related to it, the present article aims to provide a full and updated review of the field, ranging from the initial studies of the impact of math anxiety on numerical cognition, to the latest research exploring its electrophysiological correlates and brain bases from a cognitive neuroscience perspective. Finally, this review describes the factors and mechanisms that have been claimed to play a role in the origins and/or maintenance of math anxiety, and it examines in detail the main explanations proposed to account for the negative effects of math anxiety on performance: competition for working memory resources, a deficit in a low-level numerical representation, and inhibition/attentional control deficit.

  6. Modeling Longitudinal Hemispheric Differences during Geomagnetic Storm Times

    NASA Astrophysics Data System (ADS)

    Greer, K.; Immel, T. J.; Ridley, A. J.

    2014-12-01

    Work by Immel and Mannucci [2013] has indicated that geomagnetic storms causes a larger effect on the ionospheric TEC (Total Electron Count) in the American sector than anywhere else on the planet, suggesting that there is a longitude dependent (UT) effect which is important for correctly understanding the impact, structure and timing of geomagnetic storms. Here we examine the extent to which numerical models appropriately reproduce the observed results. Using Global Ionosphere-Thermosphere Model (GITM) [Ridley et al., 2006] coupled with realistic transport to examine the underlying mechanisms of the longitude-dependent storm enhancements and whether these mid-latitude enhancements are connected to high-latitude changes. TEC measurements, the Dst index, and are used in conjunction with model output.

  7. Longitudinal Hemispheric Differences During Geomagnetic Storm Times Examined with GITM

    NASA Astrophysics Data System (ADS)

    Greer, K.; Immel, T. J.; Ridley, A. J.

    2015-12-01

    Work by Immel and Mannucci [2013] has indicated that geomagnetic storms cause larger effects on the ionospheric TEC (Total Electron Count) in the American sector than anywhere else on the planet, suggesting that there is a longitude dependent (UT) effect which is important for correctly understanding the impact, structure and timing of geomagnetic storms. Using Global Ionosphere-Thermosphere Model (GITM) [Ridley et al., 2006] coupled with realistic transport, we examine the underlying mechanisms of the longitude-dependent storm enhancements. We accomplish this by using a case study storm observed on 5 August 2011 and then conducting model experiments with GITM by shifting the storm onset time over the course of 24 hours. TEC measurements, the Dst index, and IMF are used in conjunction with model output.

  8. Littoral foraging by red phalaropes during spring in the northern Bering Sea

    USGS Publications Warehouse

    Haney, J. Chris; Stone, Amy E.

    1988-01-01

    Phalaropes demonstrate considerable plasticity in their choice of foraging habitats. The Red Phalarope (Phalaropus fulicaria) alternates use of pelagic environments in winter and migration (Taning 1933, Stanford 1953, Briggs et al 1984) with wet tundra habitats during the breeding season (Kistchinski 1975, Mayfield 1979, Ridley 1980). Foods available and taken in littoral zones of the Arctic Ocean in fall have been identified (Conners and Risebrough 1978, Johnson and Richardson 1980), but otherwise little attention has been devoted to the transition between the marine and terrestrial periods of the Red Phalarope’s life history. We report phalarope use of littoral areas during spring in the northern Bering Sea and Kongkok Bay, St. Lawrence Island, Alaska. In addition, we describe phalarope foraging tactics and foods available in the sur zone, emphasizing this form of littoral foraging as an opportunistic and facultative feeding strategy.

  9. The armadillo as an animal model and reservoir host for Mycobacterium leprae.

    PubMed

    Balamayooran, Gayathriy; Pena, Maria; Sharma, Rahul; Truman, Richard W

    2015-01-01

    Apart from humans, armadillos are the only known natural hosts of Mycobacterium leprae. They are well developed as hosts for in vivo propagation of M leprae and are advancing as models for studying the pathogenesis of leprosy and translational research. Armadillos are immunologically intact. They exhibit the full Ridley-Jopling spectrum of histopathologic responses to M leprae and uniquely manifest extensive neurological involvement that closely recapitulates human leprosy. In addition, free-ranging armadillos in some regions are known to harbor a naturally occurring infection with M leprae, and zoonotic transmission between armadillos and humans has been implicated in a large number of new case presentations. We review the role of the armadillo as a model for leprosy and reservoir for human infection.

  10. Nitric oxide measurements in the Arctic winter stratosphere

    NASA Technical Reports Server (NTRS)

    Fahey, D. W.; Kawa, S. R.; Chan, K. R.

    1990-01-01

    Measurements of NO from five flights of the NASA ER-2 aircraft during the Airborne Arctic Stratospheric Expedition are presented. The NO values and vertical gradient near 60 deg N latitude are similar to previous measurements near 50 deg N in winter (Ridley et al., 1984, 1987). The NO latitudinal gradient is distinctly negative outside of the polar vortex, approaching zero at the boundary of the vortex, and remaining below the 20 pptv detection limit inside the vortex. Steady state NO2 and NO(x) (NO + NO2) are calculated from measured NO, O3, and ClO, and modeled photodissociation rates. NO(x) outside the vortex shows a negative dependence on latitude and solar zenith angle. Low NO(x) and NO(x)/NO(y), inside and near the vortex boundary may be indications of heterogeneous removal of ClONO2 and N2O5.

  11. Two new species of Halichondrida (Demospongiae) and the first record of Phycopsis and Ciocalapata for Brazil.

    PubMed

    Lage, Anaíra; Carvalho, Mariana De S; Menegola, Carla

    2013-11-06

    Two new species of the genera Phycopsis and Ciocalapata are described from the shallow waters off the Brazilian coast. This is the first record of Phycopsis in South Atlantic, with Phycopsis styloxeata sp. nov. being the only species of the genus that presents three categories of spicules: two of styles and one of oxeas. Ciocalapata, here represented by Ciocalapata minuspiculifera sp. nov., displays smaller oxeas and styles when compared to its congeneric C. amorphosa (Ridley & Dendy, 1886). The definition of this genus was modified and its geographical and bathymetric distributions now extend from the coast of Argentina to the northeastern coast of Brazil (state of Bahia) and from deep (1.097 m) to shallow (14-20 m) waters, respectively.

  12. Evidence of Fluconazole-Resistant Candida Species in Tortoises and Sea Turtles.

    PubMed

    Brilhante, Raimunda Sâmia Nogueira; Rodrigues, Pedro Henrique de Aragão; de Alencar, Lucas Pereira; Riello, Giovanna Barbosa; Ribeiro, Joyce Fonteles; de Oliveira, Jonathas Sales; Castelo-Branco, Débora de Souza Collares Maia; Bandeira, Tereza de Jesus Pinheiro Gomes; Monteiro, André Jalles; Rocha, Marcos Fábio Gadelha; Cordeiro, Rossana de Aguiar; Moreira, José Luciano Bezerra; Sidrim, José Júlio Costa

    2015-12-01

    The aim of this study was to evaluate the antifungal susceptibility of Candida spp. recovered from tortoises (Chelonoidis spp.) and sea turtles (Chelonia mydas, Caretta caretta, Lepidochelys olivacea, Eretmochelys imbricata). For this purpose, material from the oral cavity and cloaca of 77 animals (60 tortoises and 17 sea turtles) was collected. The collected specimens were seeded on 2% Sabouraud dextrose agar with chloramphenicol, and the identification was carried out by morphological and biochemical methods. Sixty-six isolates were recovered from tortoises, out of which 27 were C. tropicalis, 27 C. famata, 7 C. albicans, 4 C. guilliermondii and 1 C. intermedia, whereas 12 strains were obtained from sea turtles, which were identified as Candida parapsilosis (n = 4), Candida guilliermondii (n = 4), Candida tropicalis (n = 2), Candida albicans (n = 1) and Candida intermedia (n = 1). The minimum inhibitory concentrations for amphotericin B, itraconazole and fluconazole ranged from 0.03125 to 0.5, 0.03125 to >16 and 0.125 to >64, respectively. Overall, 19 azole-resistant strains (14 C. tropicalis and 5 C. albicans) were found. Thus, this study shows that Testudines carry azole-resistant Candida spp.

  13. Genomic variation of the fibropapilloma-associated marine turtle herpes virus across seven geographic areas and three host species

    USGS Publications Warehouse

    Greenblatt, R.J.; Quackenbush, S.L.; Casey, R.N.; Rovnak, J.; Balazs, G.H.; Work, T.M.; Casey, J.W.; Sutton, C.A.

    2005-01-01

    Fibropapillomatosis (FP) of marine turtles is an emerging neoplastic disease associated with infection by a novel turtle herpesvirus, fibropapilloma-associated turtle herpesvirus (FPTHV). This report presents 23 kb of the genome of an FPTHV infecting a Hawaiian green turtle (Chelonia mydas). By sequence homology, the open reading frames in this contig correspond to herpes simplex virus genes UL23 through UL36. The order, orientation, and homology of these putative genes indicate that FPTHV is a member of the Alphaherpesvirinae. The UL27-, UL30-, and UL34-homologous open reading frames from FPTHVs infecting nine FP-affected marine turtles from seven geographic areas and three turtle species (C. mydas, Caretta caretta, and Lepidochelys olivacea) were compared. A high degree of nucleotide sequence conservation was found among these virus variants. However, geographic variations were also found: the FPTHVs examined here form four groups, corresponding to the Atlantic Ocean, West pacific, mid-Pacific, and east Pacific. Our results indicate that FPTHV was established in marine turtle populations prior to the emergence of FP as it is currently known.

  14. Exogenous estradiol alters gonadal growth and timing of temperature sex determination in gonads of sea turtle.

    PubMed

    Díaz-Hernández, Verónica; Marmolejo-Valencia, Alejandro; Merchant-Larios, Horacio

    2015-12-01

    Temperature sex determining species offer a model for investigating how environmental cues become integrated to the regulation of patterning genes and growth, among bipotential gonads. Manipulation of steroid hormones has revealed the important role of aromatase in the regulation of the estrogen levels involved in temperature-dependent sex determination. Estradiol treatment counteracts the effect of male-promoting temperature, but the resulting ovarian developmental pattern differs from that manifested with the female-promoting temperature. Hypoplastic gonads have been reported among estradiol-treated turtles; however the estradiol effect on gonadal size has not been examined. Here we focused on the sea turtle Lepidochelys olivacea, which develops hypoplastic gonads with estradiol treatment. We studied the effect of estradiol on cell proliferation and on candidate genes involved in ovarian pattern. We found this effect is organ specific, causing a dramatic reduction in gonadal cell proliferation during the temperature-sensitive period. Although the incipient gonads resembled tiny ovaries, remodeling of the medullary cords and down-regulation of testicular factor Sox9 were considerably delayed. Contrastingly, with ovarian promoting temperature as a cue, exogenous estradiol induced the up-regulation of the ovary factor FoxL2, prior to the expression of aromatase. The strong expression of estrogen receptor alpha at the time of treatment suggests that it mediates estradiol effects. Overall results indicate that estradiol levels required for gonadal growth and to establish the female genetic network are delicately regulated by temperature.

  15. RNAi-Mediated Gene Silencing in a Gonad Organ Culture to Study Sex Determination Mechanisms in Sea Turtle

    PubMed Central

    Sifuentes-Romero, Itzel; Merchant-Larios, Horacio; Milton, Sarah L.; Moreno-Mendoza, Norma; Díaz-Hernández, Verónica; García-Gasca, Alejandra

    2013-01-01

    The autosomal Sry-related gene, Sox9, encodes a transcription factor, which performs an important role in testis differentiation in mammals. In several reptiles, Sox9 is differentially expressed in gonads, showing a significant upregulation during the thermo-sensitive period (TSP) at the male-promoting temperature, consistent with the idea that SOX9 plays a central role in the male pathway. However, in spite of numerous studies, it remains unclear how SOX9 functions during this event. In the present work, we developed an RNAi-based method for silencing Sox9 in an in vitro gonad culture system for the sea turtle, Lepidochelys olivacea. Gonads were dissected as soon as the embryos entered the TSP and were maintained in organ culture. Transfection of siRNA resulted in the decrease of both Sox9 mRNA and protein. Furthermore, we found coordinated expression patterns for Sox9 and the anti-Müllerian hormone gene, Amh, suggesting that SOX9 could directly or indirectly regulate Amh expression, as it occurs in mammals. These results demonstrate an in vitro method to knockdown endogenous genes in gonads from a sea turtle, which represents a novel approach to investigate the roles of important genes involved in sex determination or differentiation pathways in species with temperature-dependent sex determination. PMID:24705165

  16. The embryological development of primary visual centres in the turtle Emys orbicularis.

    PubMed Central

    Hergueta, S; Lemire, M; Pieau, C; Ward, R; Repérant, J

    1993-01-01

    The development of the primary visual centres was studied in a series of embryos of the turtle, Emys orbicularis, incubated at 25 degrees C. The differentiation of both visual and nonvisual diencephalic and mesencephalic structures takes place entirely within the 2nd quarter of the period of incubation; this finding appears to be consistent with previous descriptions of the embryology of 2 other chelonian species, Lepidochelys and Chelydra. Two successive waves of migration, each dividing into internal and external sheaves, are involved in the formation of the structures of the diencephalon and mesencephalon. The primary visual centres, which comprise 2 hypothalamic, 5 thalamic and 5 pretectal zones of retinal projections, together with the 2 superficial layers of the tectum and a single tegmental projection zone, all have their origin in the external sheaf of the 1st wave of migration. The finding that the adult nucleus geniculatus lateralis dorsalis, pars ventralis arises from one of the migrations of the dorsal thalamus is discussed in the context of the debate over the possible homologues of the mammalian geniculostriate visual pathway. Images Fig. 1 (cont.) Fig. 1 Fig. 2 (cont.) Fig. 2 Fig. 3 (cont.) Fig. 3 Fig. 4 (cont.) Fig. 4 Fig. 5 (cont.) Fig. 5 Fig. 6 (cont.) Fig. 6 Fig. 7 Fig. 8 (cont.) Fig. 8 Fig. 9 (cont.) Fig. 9 Fig. 10 (cont.) Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 PMID:8300423

  17. The dynamics in the upper atmospheres of Mars and Titan

    NASA Astrophysics Data System (ADS)

    Bell, Jared M.

    2008-06-01

    This thesis explores the dynamics of two terrestrial bodies: Mars and Titan. At Mars, the coupled Mars General Circulation Model - Mars Thermospheric General Circulation Model (MGCM-MTGCM) is employed to investigate the phenomenon known as Mars winter polar warming. At Titan, a new theoretical model, the Titan Global Ionosphere - Thermosphere Model (T-GITM), is developed, based upon previous work by Ridley et al. [2006]. Using this new model, three separate numerical studies quantify the impacts of solar cycle, seasons, and lower boundary zonal winds on the Titan thermosphere structure and dynamics. At Mars, this thesis investigates thermospheric winter polar warming through three major studies: (1) a systematic analysis of vertical dust mixing in the lower atmosphere and its impact upon the dynamics of the lower thermosphere (100-130 km), (2) an interannual investigation utilizing three years of lower atmosphere infrared (IR) dust optical depth data acquired by the Thermal Emission Spectrometer (TES) instrument on board Mars Global Surveyor (MGS), and finally (3) a brief study of the MTGCM's response to variations in upward propagating waves and tides from the lower atmosphere. Ultimately, this investigation suggests that an interhemispheric summer-to-winter Hadley circulation, originating in the lower atmosphere and extending into the upper atmosphere, is responsible for thermospheric winter polar warming [ Bell etal. , 2007]. A major branch of this thesis builds upon the previous work of Müller-Wodarg et al. [2000], Müller-Wodarg et al. [2003], M7uuml;ller-Wodarg et al. [2006], and Yelle et al. [2006] as it attempts to explain the structures in Titan's upper atmosphere, between 500-1500 km. Building also upon the recent development of GITM by Ridley et al. [2006], this thesis presents a new theoretical framework, T-GITM. This model is then employed to conduct a series of numerical experiments to quantify the impacts of the solar cycle, the season, and the

  18. The Gulf Coast Vulnerability Assessment: Mangrove, Tidal Emergent Marsh, Barrier Islands, and Oyster Reef

    USGS Publications Warehouse

    Watson, Amanda; Reece, Joshua S.; Tirpak, Blair; Edwards, Cynthia Kallio; Geselbracht, Laura; Woodrey, Mark; LaPeyre, Megan K.; Dalyander, P. Soupy

    2015-01-01

    Climate, sea level rise, and urbanization are undergoing unprecedented levels of combined change and are expected to have large effects on natural resources—particularly along the Gulf of Mexico coastline (Gulf Coast). Management decisions to address these effects (i.e., adaptation) require an understanding of the relative vulnerability of various resources to these stressors. To meet this need, the four Landscape Conservation Cooperatives along the Gulf partnered with the Gulf of Mexico Alliance to conduct this Gulf Coast Vulnerability Assessment (GCVA). Vulnerability in this context incorporates the aspects of exposure and sensitivity to threats, coupled with the adaptive capacity to mitigate those threats. Potential impact and adaptive capacity reflect natural history features of target species and ecosystems. The GCVA used an expert opinion approach to qualitatively assess the vulnerability of four ecosystems: mangrove, oyster reef, tidal emergent marsh, and barrier islands, and a suite of wildlife species that depend on them. More than 50 individuals participated in the completion of the GCVA, facilitated via Ecosystem and Species Expert Teams. Of the species assessed, Kemp’s ridley sea turtle was identified as the most vulnerable species across the Gulf Coast. Experts identified the main threats as loss of nesting habitat to sea level rise, erosion, and urbanization. Kemp’s ridley also had an overall low adaptive capacity score due to their low genetic diversity, and higher nest site fidelity as compared to other assessed species. Tidal emergent marsh was the most vulnerable ecosystem, due in part to sea level rise and erosion. In general, avian species were more vulnerable than fish because of nesting habitat loss to sea level rise, erosion, and potential increases in storm surge. Assessors commonly indicated a lack of information regarding impacts due to projected changes in the disturbance regime, biotic interactions, and synergistic effects in both

  19. Sea-surface temperature gradients across blue whale and sea turtle foraging trajectories off the Baja California Peninsula, Mexico

    NASA Astrophysics Data System (ADS)

    Etnoyer, Peter; Canny, David; Mate, Bruce R.; Morgan, Lance E.; Ortega-Ortiz, Joel G.; Nichols, Wallace J.

    2006-02-01

    Sea-surface temperature (SST) fronts are integral to pelagic ecology in the North Pacific Ocean, so it is necessary to understand their character and distribution, and the way these features influence the behavior of endangered and highly migratory species. Here, telemetry data from sixteen satellite-tagged blue whales ( Balaenoptera musculus) and sea turtles ( Caretta caretta, Chelonia mydas, and Lepidochelys olivacea) are employed to characterize 'biologically relevant' SST fronts off Baja California Sur. High residence times are used to identify presumed foraging areas, and SST gradients are calculated across advanced very high resolution radiometer (AVHRR) images of these regions. The resulting values are compared to classic definitions of SST fronts in the oceanographic literature. We find subtle changes in surface temperature (between 0.01 and 0.10 °C/km) across the foraging trajectories, near the lowest end of the oceanographic scale (between 0.03 and 0.3 °C/km), suggesting that edge-detection algorithms using gradient thresholds >0.10 °C/km may overlook pelagic habitats in tropical waters. We use this information to sensitize our edge-detection algorithm, and to identify persistent concentrations of subtle SST fronts in the Northeast Pacific Ocean between 2002 and 2004. The lower-gradient threshold increases the number of fronts detected, revealing more potential habitats in different places than we find with a higher-gradient threshold. This is the expected result, but it confirms that pelagic habitat can be overlooked, and that the temperature gradient parameter is an important one.

  20. Physical and Chemical Properties of Some Imported Woods and their Degradation by Termites

    PubMed Central

    Shanbhag, Rashmi R.; Sundararaj, R.

    2013-01-01

    The influence of physical and chemical properties of 20 species of imported wood on degradation of the wood by termites under field conditions was studied. The wood species studied were: Sycamore maple, Acer pseudoplatanus L. (Sapindales: Sapindaceae) (from two countries), Camphor, Dryobalanops aromatic C.F.Gaertner (Malvales: Dipterocarpaceae), Beech, Fagus grandifolia Ehrhart (Fagales: Fagaceae), F. sylvatica L. (from two countries), Oak, Quercus robur L., Ash, Fraxinus angustifolia Vahl (Lamiales: Oleaceae), F. excelsior L., Padauk, Pterocarpus soyauxii Taubert (Fabales: Fabaceae), (from two countries), Jamba, Xylia dolabrifiormis Roxburgh, Shorea laevis Ridley (Malvales: Dipterocarpaceae), S. macoptera Dyer, S. robusta Roth, Teak, Tectona grandis L.f. (Lamiales: Lamiaceae) (from five countries), and rubber tree, Hevea brasiliensis Müller Argoviensis (Malpighiales: Euphorbiaceae) from India. The termites present were: Odontotermes horni (Wasmann) (Isoptera: Termitidae), O. feae, O. wallonensis, and O. obeus (Rambur). A significant conelation was found between density, cellulose, lignin, and total phenolic contents of the wood and degradation by termites. The higher the density of the wood, the lower the degradation. Similarly, higher amount of lignin and total phenolic contents ensured higher resistance, whereas cellulose drives the termites towards the wood. PMID:23906349

  1. Phosphorylation of the growth arrest-specific protein Gas2 is coupled to actin rearrangements during Go-->G1 transition in NIH 3T3 cells

    PubMed Central

    1994-01-01

    Growth arrest-specific (Gas2) protein has been shown to be a component of the microfilament system, that is highly expressed in growth arrested mouse and human fibroblasts and is hyperphosphorylated upon serum stimulation of quiescent cells. (Brancolini, C., S. Bottega, and C. Schneider. 1992. J. Cell Biol. 117:1251-1261). In this study we demonstrate that the kinetics of Gas2 phosphorylation, during Go-->G1 transition, as induced by addition of 20% FCS to serum starved NIH 3T3 cells, is temporally coupled to the reorganization of actin cytoskeleton. To better dissect the relationship between Gas2 phosphorylation and the modification of the microfilament architecture we used specific stimuli for both membrane ruffling (PDGF and PMA) and stress fiber formation (L-alpha-lysophosphatidic acid LPA) (Ridley, A. J., and A. Hall. 1992. Cell. 70:389-399). All of them, similarly to 20% FCS, are able to downregulate Gas2 biosynthesis. PDGF and PMA induce Gas2 hyperphosphorylation that is temporally coupled with the appearance of membrane ruffling where Gas2 localizes. On the other hand LPA, a specific stimulus for stress fiber formation, fails to induce a detectable Gas2 hyperphosphorylation. Thus, Gas2 hyperphosphorylation is specifically correlated with the formation of membrane ruffling possibly implying a role of Gas2 in this process. PMID:8120096

  2. Description of leprosy classification at baseline among patients enrolled at the uniform multidrug therapy clinical trial for leprosy patients in Brazil.

    PubMed

    Moura, Rodrigo Scaliante; Penna, Gerson Oliveira; Cardoso, Ludimila Paula Vaz; de Andrade Pontes, Maria Araci; Cruz, Rossilene; de Sá Gonçalves, Heitor; Fernandes Penna, Maria Lúcia; de Araújo Stefani, Mariane Martins; Bührer-Sékula, Samira

    2015-06-01

    The uniform multidrug therapy clinical trial, Brazil (U-MDT/CT-BR), database was used to describe and report the performance of available tools to classify 830 leprosy patients as paucibacillary (PB) and multibacillary (MB) at baseline. In a modified Ridley and Jopling (R&J) classification, considering clinical features, histopathological results of skin biopsies and the slit-skin smear bacterial load results were used as the gold standard method for classification. Anti-phenolic glycolipid-I (PGL-I) serology by ML Flow test, the slit skin smear bacterial load, and the number of skin lesions were evaluated. Considering the R&J classification system as gold standard, ML Flow tests correctly allocated 70% patients in the PB group and 87% in the MB group. The classification based on counting the number of skin lesions correctly allocated 46% PB patients and 99% MB leprosy cases. Slit skin smears properly classified 91% and 97% of PB and MB patients, respectively. Based on U-MDT/CT-BR results, classification of leprosy patients for treatment purposes is unnecessary because it does not impact clinical and laboratories outcomes. In this context, the identification of new biomarkers to detect patients at a higher risk to develop leprosy reactions or relapse remains an important research challenge.

  3. Update on the epidemiology, diagnosis, and treatment of leprosy.

    PubMed

    Reibel, F; Cambau, E; Aubry, A

    2015-09-01

    Leprosy is an infectious disease that has now been reported for more than 2000 years. The leprosy elimination goal set by the World Health Organization (WHO), i.e. a global prevalence rate <1 patient per 10,000 population, was achieved in the year 2000, but more than 200,000 new case patients are still reported each year, particularly in India, Brazil, and Indonesia. Leprosy is a specific infection: (i) it is a chronic infection primarily affecting the skin and peripheral nerves, (ii) Mycobacterium leprae is one of the last bacterial species of medical interest that cannot be cultured in vitro (mainly because of its reductive genome evolution), and (iii) transmission and pathophysiological data is still limited. The various presentations of the disease (Ridley-Jopling and WHO classifications) are correlated with the patient's immune response, bacillary load, and by the delay before diagnosis. Multidrug therapy (dapsone, rifampicin, with or without clofazimine) has been recommended since 1982 as the standard treatment of leprosy; 6 months for patients presenting with paucibacillary leprosy and 12 months for patients presenting with multibacillary leprosy. The worldwide use of leprosy drugs started in the 1980s and their free access since 1995 contributed to the drastic decline in the number of new case patients. Resistant strains are however emerging despite the use of multidrug therapy; identifying and monitoring resistance is still necessary.

  4. Fine needle aspiration cytology as an aid to diagnosis, categorization and treatment when pure neuritic leprosy presents as nerve abscess

    PubMed Central

    Kiran, C M; Menon, Roshni

    2013-01-01

    Background: Pure neuritic leprosy (PNL) usually presents with neurological symptoms without skin involvement. Fine needle aspiration can play an important role in the management of PNL cases presenting as nerve abscesses. Aim: To assess the role of fine needle aspiration cytology (FNAC) in diagnosing and categorizing PNL cases presenting as nerve abscesses in the absence of neurological symptoms. Materials and Methods: Five patients with subcutaneous nerve related swellings without clinically evident neurological deficits were subjected to FNAC. As the cytological features were suggestive of nerve abscesses due to leprosy, Fite stain was performed in all cases. As none of the patients had any leprosy skin lesions, they were diagnosed as cases of PNL. Features like cellularity, caseous necrosis, presence or absence of lymphocytes, macrophages, epithelioid cells, granulomas, Langhans giant cells and nerve elements were analyzed with the bacteriological index, to categorize PNL according to the Ridley-Jopling classification. Results: Based on the cytological features and bacteriological indices, 3 cases were cytologically categorized into tuberculoid (TT)/borderline tuberculoid (BT) leprosy and the other two, as BT/borderline lepromatous (BL) and BL leprosy respectively in spite of having similar clinical presentation. Based on the cytological diagnoses, category-specific treatment could be instituted with clinical improvement. Conclusions: The simple and minimally invasive FNAC procedure allows diagnosis and a reasonably accurate categorization of PNL presenting as nerve abscess and therefore, highly useful in its clinical management. PMID:24648666

  5. Capturing Change: Integrating Art and Science

    NASA Astrophysics Data System (ADS)

    Gillerman, J.

    2011-12-01

    The evolving capabilities of interactive media have broadened the potential, and the challenges, of sharing scientific knowledge. From video capture to mobile devices, new technologies have enabled artists to tackle previously demanding or out-of-reach topics and new avenues of dissemination of both art and science. These changes and capabilities affect not only the context and possibilities of scientific data collection, but also how information is presented and communicated innovatively to the public. When recording video of science material whether it is of a Ridley Sea Turtle laying eggs on a beach in Costa Rica, an active lava flow from the volcano Kilauea in Hawaii, or solar eclipses in remote locations around the world, one has to be prepared technically and artistically, not to mention patient in specialized and/or challenging conditions to capture video that satisfies the scientific and artistic imagination. This presentation will include material from varied natural phenomena, creative interfacing in a multimedia context integrating art, science, culture and technology to reach a broad and diverse public, and teaching the integration of art and science through varied art media. (http://www.vipervertex.com).

  6. Storm time plasma transport in a unified and inter-coupled global magnetosphere model

    NASA Astrophysics Data System (ADS)

    Ilie, R.; Liemohn, M. W.; Toth, G.

    2014-12-01

    We present results from the two-way self-consistent coupling between the kinetic Hot Electron and Ion Drift Integrator (HEIDI) model and the Space Weather Modeling Framework (SWMF). HEIDI solves the time dependent, gyration and bounced averaged kinetic equation for the phase space density of different ring current species and computes full pitch angle distributions for all local times and radial distances. During geomagnetic times the dipole approximation becomes unsuitable even in the inner magnetosphere. Therefore the HEIDI model was generalized to accommodate an arbitrary magnetic field and through the coupling with SWMF it obtains a magnetic field description throughout the HEIDI domain along with a plasma distribution at the model outer boundary from the Block Adaptive Tree Solar Wind Roe Upwind Scheme (BATS-R-US) magnetohydrodynamics (MHD) model within SWMF. Electric field self-consistency is assured by the passing of convection potentials from the Ridley Ionosphere Model (RIM) within SWMF. In this study we test the various levels of coupling between the 3 physics based models, highlighting the role that the magnetic field, plasma sheet conditions and the cross polar cap potential play in the formation and evolution of the ring current. We show that the dynamically changing geospace environment itself plays a key role in determining the geoeffectiveness of the driver. The results of the self-consistent coupling between HEIDI, BATS-R-US and RIM during disturbed conditions emphasize the importance of a kinetic self-consistent approach to the description of geospace.

  7. Two-way self-consistent coupling of HEIDI in SWMF

    NASA Astrophysics Data System (ADS)

    Ilie, R.; Liemohn, M. W.; Toth, G.

    2013-12-01

    In this study we present results from the two-way coupling between the kinetic Hot Electron and Ion Drift Integrator (HEIDI) model and the Space Weather Modeling Framework (SWMF). HEIDI solves the time dependent, gyration and bounced averaged kinetic equation for the phase space density of different ring current species and computes full pitch angle distributions for all local times and radial distances. This model was generalized to accommodate an arbitrary magnetic field and, through the coupling with SWMF, it obtains the magnetic field description along with the plasma distribution at the model boundaries from the Block Adaptive Tree Solar Wind Roe Upwind Scheme (BATS-R-US) magnetohydrodynamics (MHD) model within the SWMF. Electric field self-consistency is assured by the passing of convection potentials from the Ridley Ionosphere Model (RIM) within SWMF. Our study tests the various levels of coupling between the 3 models, highlighting the roles that the magnetic field, plasma sheet conditions and the cross polar cap potential play in the formation and evolution of the ring current. The results of the self-consistent coupling between HEIDI, BATSRUS and RIM during disturbed conditions emphasize the importance of a kinetic self-consistent approach to the description of the geospace.

  8. Validation of the SWMF Magnetosphere: Fields and Particles

    NASA Astrophysics Data System (ADS)

    Welling, D. T.; Ridley, A. J.

    2009-05-01

    The Space Weather Modeling Framework has been developed at the University of Michigan to allow many independent space environment numerical models to be executed simultaneously and coupled together to create a more accurate, all-encompassing system. This work explores the capabilities of the framework when using the BATS-R-US MHD code, Rice Convection Model (RCM), the Ridley Ionosphere Model (RIM), and the Polar Wind Outflow Model (PWOM). Ten space weather events, ranging from quiet to extremely stormy periods, are modeled by the framework. All simulations are executed in a manner that mimics an operational environment where fewer resources are available and predictions are required in a timely manner. The results are compared against in-situ measurements of magnetic fields from GOES, Polar, Geotail, and Cluster satellites as well as MPA particle measurements from the LANL geosynchronous spacecraft. Various metrics are calculated to quantify performance. Results when using only two to all four components are compared to evaluate the increase in performance as new physics are included in the system.

  9. Solar wind density controlling penetration electric field at the equatorial ionosphere during a saturation of cross polar cap potential

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Wan, W.; Zhao, B.; Hong, M.; Ridley, A.; Ren, Z.; Fraenz, M.; Dubinin, E.; He, M.

    2012-09-01

    The most important source of electrodynamic disturbances in the equatorial ionosphere during the main phase of a storm is the prompt penetration electric field (PPEF) originating from the high-latitude region. It has been known that such an electric field is correlated with the magnetospheric convection or interplanetary electric field. Here we show a unique case, in which the electric field disturbance in the equatorial ionosphere cannot be interpreted by this concept. During the superstorm on Nov. 20-21, 2003, the cross polar cap potential (CPCP) saturated at least for 8.2 h. The CPCP reconstructed by Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure suggested that the PPEF at the equatorial ionosphere still correlated with the saturated CPCP, but the CPCP was controlled by the solar wind density instead of the interplanetary electric field. However, the predicted CPCPs by Hill-Siscoe-Ober (HSO) model and Boyle-Ridley (BR) model were not fully consistent with the AMIE result and PPEF. The PPEF also decoupled from the convection electric field in the magnetotail. Due to the decoupling, the electric field in the ring current was not able to comply with the variations of PPEF, and this resulted in a long-duration electric field penetration without shielding.

  10. Voluntary enhancement of neural signatures of affiliative emotion using FMRI neurofeedback.

    PubMed

    Moll, Jorge; Weingartner, Julie H; Bado, Patricia; Basilio, Rodrigo; Sato, João R; Melo, Bruno R; Bramati, Ivanei E; de Oliveira-Souza, Ricardo; Zahn, Roland

    2014-01-01

    In Ridley Scott's film "Blade Runner", empathy-detection devices are employed to measure affiliative emotions. Despite recent neurocomputational advances, it is unknown whether brain signatures of affiliative emotions, such as tenderness/affection, can be decoded and voluntarily modulated. Here, we employed multivariate voxel pattern analysis and real-time fMRI to address this question. We found that participants were able to use visual feedback based on decoded fMRI patterns as a neurofeedback signal to increase brain activation characteristic of tenderness/affection relative to pride, an equally complex control emotion. Such improvement was not observed in a control group performing the same fMRI task without neurofeedback. Furthermore, the neurofeedback-driven enhancement of tenderness/affection-related distributed patterns was associated with local fMRI responses in the septohypothalamic area and frontopolar cortex, regions previously implicated in affiliative emotion. This demonstrates that humans can voluntarily enhance brain signatures of tenderness/affection, unlocking new possibilities for promoting prosocial emotions and countering antisocial behavior.

  11. Non-equilibrium optical phonon dynamics in bulk and low-dimensional semiconductors

    NASA Astrophysics Data System (ADS)

    Srivastava, G. P.

    2007-02-01

    We present theoretical investigations of the intrinsic dynamics of long-wavelength non-equilibrium optical phonons in bulk and low-dimensional semiconductors. The theory is based on the application of Fermi's golden rule formula, with phonon dispersion relations as well as crystal anharmonicity considered in the framework of isotropic continuum model. Contributions to the decay rates of the phonon modes are discussed in terms of four possible channels: Klemens channel (into two acoustic daughter modes), generalised Ridley channel (into one acoustic and one optical mode), generalised Vallee-Bogani channel (into a lower mode of the same branch and an acoustic mode), and Barman-Srivastava channel (into two lower-branch optical modes). The role of crystal structure and cation/anion mass ratio in determining the lifetime of such modes in bulk semiconductors is highlighted. Estimates of lifetimes of such modes in silicon nanowires and carbon nanotubes will also be presented. The results support and explain available experimental data, and make predictions in some cases.

  12. Quantitative Assessment of the CCMC's Experimental Real-time SWMF-Geospace Results

    NASA Astrophysics Data System (ADS)

    Liemohn, Michael; Ganushkina, Natalia; De Zeeuw, Darren; Welling, Daniel; Toth, Gabor; Ilie, Raluca; Gombosi, Tamas; van der Holst, Bart; Kuznetsova, Maria; Maddox, Marlo; Rastaetter, Lutz

    2016-04-01

    Experimental real-time simulations of the Space Weather Modeling Framework (SWMF) are conducted at the Community Coordinated Modeling Center (CCMC), with results available there (http://ccmc.gsfc.nasa.gov/realtime.php), through the CCMC Integrated Space Weather Analysis (iSWA) site (http://iswa.ccmc.gsfc.nasa.gov/IswaSystemWebApp/), and the Michigan SWMF site (http://csem.engin.umich.edu/realtime). Presently, two configurations of the SWMF are running in real time at CCMC, both focusing on the geospace modules, using the BATS-R-US magnetohydrodynamic model, the Ridley Ionosphere Model, and with and without the Rice Convection Model for inner magnetospheric drift physics. While both have been running for several years, nearly continuous results are available since July 2015. Dst from the model output is compared against the Kyoto real-time Dst, in particular the daily minimum value of Dst to quantify the ability of the model to capture storms. Contingency tables are presented, showing that the run with the inner magnetosphere model is much better at reproducing storm-time values. For disturbances with a minimum Dst lower than -50 nT, this version yields a probability of event detection of 0.86 and a Heidke Skill Score of 0.60. In the other version of the SWMF, without the inner magnetospheric module included, the modeled Dst never dropped below -50 nT during the examined epoch.

  13. Environmental dynamics of red Noctiluca scintillans bloom in tropical coastal waters.

    PubMed

    Baliarsingh, S K; Lotliker, Aneesh A; Trainer, Vera L; Wells, Mark L; Parida, Chandanlal; Sahu, Biraja K; Srichandan, Suchismita; Sahoo, Subhashree; Sahu, K C; Kumar, T Sinivasa

    2016-10-15

    An intense bloom of red Noctiluca scintillans (NS) occurred off the Rushikulya estuarine region along the east coast of India, an important site for mass nesting events of the vulnerable Olive Ridley sea turtle. At its peak, densities of NS were 3.3×10(5) cells-l(-1), with low relative abundance of other phytoplankton. The peak bloom coincided with high abundance of gelatinous planktivores which may have facilitated bloom development by their grazing on other zooplankton, particularly copepods. Ammonium concentrations increased by approximately 4-fold in the later stages of bloom, coincident with stable NS abundance and chlorophyll concentrations in the nano- and microplankton. This increase likely was attributable to release of intracellular ammonium accumulated through NS grazing. Dissolved oxygen concentrations decreased in sub-surface waters to near hypoxia. Micro-phytoplankton increasingly dominated chlorophyll-a biomass as the bloom declined, with diminishing picoplankton abundance likely the result of high predation by the ciliate Mesodinium rubrum. Together, these data illustrate factors that can disrupt ecosystem balance in this critically important Indian coastal region.

  14. Physical and chemical properties of some imported woods and their degradation by termites.

    PubMed

    Shanbhag, Rashmi R; Sundararaj, R

    2013-01-01

    The influence of physical and chemical properties of 20 species of imported wood on degradation of the wood by termites under field conditions was studied. The wood species studied were: Sycamore maple, Acer pseudoplatanus L. (Sapindales: Sapindaceae) (from two countries), Camphor, Dryobalanops aromatic C.F.Gaertner (Malvales: Dipterocarpaceae), Beech, Fagus grandifolia Ehrhart (Fagales: Fagaceae), F. sylvatica L. (from two countries), Oak, Quercus robur L., Ash, Fraxinus angustifolia Vahl (Lamiales: Oleaceae), F. excelsior L., Padauk, Pterocarpus soyauxii Taubert (Fabales: Fabaceae), (from two countries), Jamba, Xylia dolabrifiormis Roxburgh, Shorea laevis Ridley (Malvales: Dipterocarpaceae), S. macoptera Dyer, S. robusta Roth, Teak, Tectona grandis L.f. (Lamiales: Lamiaceae) (from five countries), and rubber tree, Hevea brasiliensis Müller Argoviensis (Malpighiales: Euphorbiaceae) from India. The termites present were: Odontotermes horni (Wasmann) (Isoptera: Termitidae), O. feae, O. wallonensis, and O. obeus (Rambur). A significant conelation was found between density, cellulose, lignin, and total phenolic contents of the wood and degradation by termites. The higher the density of the wood, the lower the degradation. Similarly, higher amount of lignin and total phenolic contents ensured higher resistance, whereas cellulose drives the termites towards the wood.

  15. Quantitative analysis of herpes virus sequences from normal tissue and fibropapillomas of marine turtles with real-time PCR

    USGS Publications Warehouse

    Quackenbush, S.L.; Casey, R.N.; Murcek, R.J.; Paul, T.A.; Work, T.M.; Limpus, C.J.; Chaves, A.; duToit, L.; Perez, J.V.; Aguirre, A.A.; Spraker, T.R.; Horrocks, J.A.; Vermeer, L.A.; Balazs, G.S.; Casey, J.W.

    2001-01-01

    Quantitative real-time PCR has been used to measure fibropapilloma-associated turtle herpesvirus (FPTHV) pol DNA loads in fibropapillomas, fibromas, and uninvolved tissues of green, loggerhead, and olive ridley turtles from Hawaii, Florida, Costa Rica, Australia, Mexico, and the West Indies. The viral DNA loads from tumors obtained from terminal animals were relatively homogenous (range 2a??20 copies/cell), whereas DNA copy numbers from biopsied tumors and skin of otherwise healthy turtles displayed a wide variation (range 0.001a??170 copies/cell) and may reflect the stage of tumor development. FPTHV DNA loads in tumors were 2.5a??4.5 logs higher than in uninvolved skin from the same animal regardless of geographic location, further implying a role for FPTHV in the etiology of fibropapillomatosis. Although FPTHV pol sequences amplified from tumors are highly related to each other, single signature amino acid substitutions distinguish the Australia/Hawaii, Mexico/Costa Rica, and Florida/Caribbean groups.

  16. Chemical modeling constraints on Martian surface mineralogies formed in an early, warm, wet climate, and speculations on the occurrence of phosphate minerals in the Martian regolith

    NASA Technical Reports Server (NTRS)

    Plumlee, Geoffrey S.; Ridley, W. Ian; Debraal, Jeffrey D.

    1992-01-01

    This is one in a series of reports summarizing our chemical modeling studies of water-rock-gas interactions at the martian surface through time. The purpose of these studies is to place constraints on possible mineralogies formed at the martian surface and to model the geochemical implications of martian surficial processes proposed by previous researchers. Plumlee and Ridley summarize geochemical processes that may have occurred as a result of inferred volcano- and impact-driven hydrothermal activity on Mars. DeBraal et al. model the geochemical aspects of water-rock interactions and water evaporation near 0 C, as a prelude to future calculations that will model sub-0 C brine-rock-clathrate interactions under the current martian climate. In this report, we discuss reaction path calculations that model chemical processes that may have occurred at the martian surface in a postulated early, warm, wet climate. We assume a temperature of 25 C in all our calculations. Processes we model here include (1) the reaction of rainwater under various ambient CO2 and O2 pressures with basaltic rocks at the martian surface, (2) the formation of acid rain by volcanic gases such as HCl and SO2, (3) the reactions of acid rain with basaltic surficial materials, and (4) evaporation of waters resulting from rainwater-basalt interactions.

  17. The effect of magnetopause motion on fast mode resonance

    NASA Astrophysics Data System (ADS)

    Hartinger, M. D.; Welling, D.; Viall, N. M.; Moldwin, M. B.; Ridley, A.

    2014-10-01

    The Earth's magnetosphere supports several types of ultralow frequency (ULF) waves. These include fast mode resonance (FMR): cavity modes, waveguide modes, and tunneling modes/virtual resonance. The magnetopause, often treated as the outer boundary for cavity/waveguide modes in the dayside magnetosphere, is not stationary. A rapidly changing outer boundary condition—e.g., due to rapid magnetopause motion—is not favorable for FMR generation and may explain the sparseness of FMR observations in the outer magnetosphere. We examine how magnetopause motion affects the dayside magnetosphere's ability to sustain FMR with idealized Space Weather Modeling Framework (SWMF) simulations using the BATS-R-US global magnetohydrodynamic (MHD) code coupled with the Ridley Ionosphere Model (RIM). We present observations of FMR in BATS-R-US, reproducing results from other global MHD codes. We further show that FMR is present for a wide range of solar wind conditions, even during periods with large and rapid magnetopause displacements. We compare our simulation results to FMR observations in the dayside magnetosphere, finding that FMR occurrence does not depend on solar wind dynamic pressure, which can be used as a proxy for dynamic pressure fluctuations and magnetopause perturbations. Our results demonstrate that other explanations besides a nonstationary magnetopause—such as the inability to detect FMR in the presence of other ULF wave modes with large amplitudes—are required to explain the rarity of FMR observations in the outer magnetosphere.

  18. Faecal Parasitology: Concentration Methodology Needs to be Better Standardised

    PubMed Central

    Manser, Monika M.; Saez, Agatha Christie Santos; Chiodini, Peter L.

    2016-01-01

    Aim To determine whether variation in the preservative, pore size of the sieve, solvent, centrifugal force and centrifugation time used in the Ridley-Allen Concentration method for examining faecal specimens for parasite stages had any effect on their recovery in faecal specimens. Methods A questionnaire was sent to all participants in the UK NEQAS Faecal Parasitology Scheme. The recovery of parasite stages was compared using formalin diluted in water or formalin diluted in saline as the fixative, 3 different pore sizes of sieve, ether or ethyl acetate as a solvent, 7 different centrifugal forces and 6 different centrifugation times according to the methods described by participants completing the questionnaire. Results The number of parasite stages recovered was higher when formalin diluted in water was used as fixative, a smaller pore size of sieve was used, ethyl acetate along with Triton X 100 was used as a solvent and a centrifugal force of 3,000 rpm for 3 minutes were employed. Conclusions This study showed that differences in methodology at various stages of the concentration process affect the recovery of parasites from a faecal specimen and parasites present in small numbers could be missed if the recommended methodology is not followed. PMID:27073836

  19. Spin decoherence in n-type GaAs: The effectiveness of the third-body rejection method for electron-electron scattering

    SciTech Connect

    Marchetti, Gionni Hodgson, Matthew D'Amico, Irene

    2014-10-28

    We study the spin decoherence in n-type bulk GaAs for moderate electronic densities at room temperature using the Ensemble Monte Carlo method. We demonstrate that a technique called “third-body rejection method” devised by B. K. Ridley, J. Phys. C: Solid State Phys. 10, 1589 (1977) can be successfully adapted to Ensemble Monte Carlo method and used to tackle the problem of the electron-electron contribution to spin decoherence in the parameter region under study, where the electron-electron interaction can be reasonably described by a Yukawa potential. This scattering technique is employed in a doping region where one can expect that multiple collisions may play a role in carrier dynamics. By this technique, we are able to calculate spin relaxation times which are in very good agreement with the experimental results found by Oertel et al., Appl. Phys. Lett. 93, 13 (2008). Through this method, we show that the electron-electron scattering is overestimated in Born approximation, in agreement with previous results obtained by C. A. Kukkonen and H. Smith, Phys. Rev. B 8, 4601 (1973).

  20. Spin decoherence in n-type GaAs: The effectiveness of the third-body rejection method for electron-electron scattering

    NASA Astrophysics Data System (ADS)

    Marchetti, Gionni; Hodgson, Matthew; D'Amico, Irene

    2014-10-01

    We study the spin decoherence in n-type bulk GaAs for moderate electronic densities at room temperature using the Ensemble Monte Carlo method. We demonstrate that a technique called "third-body rejection method" devised by B. K. Ridley, J. Phys. C: Solid State Phys. 10, 1589 (1977) can be successfully adapted to Ensemble Monte Carlo method and used to tackle the problem of the electron-electron contribution to spin decoherence in the parameter region under study, where the electron-electron interaction can be reasonably described by a Yukawa potential. This scattering technique is employed in a doping region where one can expect that multiple collisions may play a role in carrier dynamics. By this technique, we are able to calculate spin relaxation times which are in very good agreement with the experimental results found by Oertel et al., Appl. Phys. Lett. 93, 13 (2008). Through this method, we show that the electron-electron scattering is overestimated in Born approximation, in agreement with previous results obtained by C. A. Kukkonen and H. Smith, Phys. Rev. B 8, 4601 (1973).

  1. Monitoring interactions between red-cockaded woodpeckers and southern flying squirrels.

    SciTech Connect

    Risch, Thomas S; Loeb, Susan C

    2004-12-31

    Risch, Thomas S., and Susan C. Loeb. 2004. Monitoring interactions between red-cockaded woodpeckers and southern flying squirrels. In: Red-cockaded woodpecker; Road to Recovery. Proceedings of the 4th Red-cockaded woodpecker Symposium. Ralph Costa and Susan J. Daniels, eds. Savannah, Georgia. January, 2003. Chapter 8. Cavities, Cavity Trees, and Cavity Communities. Pp 504-505. Abstract: Although several studies have suggested that southern flying squirrels (Glaucomys volans) may have a significant negative impact on red-cockades woodpeckers (Picoides borealsi) (Loeb and Hooper 1997, Laves and Loeb 1999), the nature of the interactions between the species remains unclear. Particularly lacking are data that address if southern flying squirrels directly usurp red-cockaded woodpecker s from cavities, or simply occupy cavities previously abandoned by red-cockaded woodpeckers. Ridley et al. (1997) observed the displacement of a red-cockaded woodpecker by a southern flying squirrel that was released after being captured. Observations of nocturnal displacements of red-cockaded woodpeckers by flying squirrels, however, are lacking. Due to the difficulty of observing interspecific interactions, determining the mechanisims by which flying squirrels impact red-cockaded woodpeckers is problematic.

  2. Intrusive LIPs: Deep crustal magmatic processes during the emplacement of Large Igneous Provinces

    NASA Astrophysics Data System (ADS)

    Richards, M. A.; Karlstrom, L.

    2011-12-01

    Large Igneous Provinces (LIPs) are characterized by magmatic activity on two distinct timescales. While these provinces have total active lifetimes of order 10-30 Ma, most of the erupted volume is emplaced within <1 Ma in many cases. The latter timescale is likely controlled by magmatic intrusion/evolution processes within the deep crust. We present seismic evidence for 5-15 km thick Moho-level ultramafic intrusive/cumulate layers underlying Phanerozoic LIPs worldwide [Ridley and Richards, 2010]. These deep crustal bodies are both observed and predicted to have volumes at least as large as the extrusive components of flood volcanism. The evidence for these layers is particularly clear for oceanic LIPs (plateaus). We hypothesize that thermally activated creep of the lower crust due to magma chamber emplacement controls a transition from largely extrusive to largely intrusive magmatism during mantle plume impingement on the lithosphere [Karlstrom and Richards, 2011]. We explore this hypothesis by modeling the thermomechanical evolution of Moho-level magma chambers. Comparing the timescale for viscoelastic relaxation of intrusion-related stresses with the timescale for sill formation and magma differentiation, we find that fracture processes leading to diking from Moho levels may plausibly be shut off on a timescale of ~1 Ma. Continued melt influx therefore results in intrusive magmatism, which may be manifest as plateau growth in oceanic settings. We suggest that maximum intrusion size may be limited by crustal thickness, resulting in smaller volume individual eruptions in oceanic versus continental LIPs.

  3. Modeling ionospheric electron precipitation due to wave particle scattering in the magnetosphere and the feedback effect on the magnetospheric dynamics

    NASA Astrophysics Data System (ADS)

    Yu, Y.; Jordanova, V.; Ridley, A. J.; Albert, J.; Horne, R. B.; Jeffery, C. A.

    2015-12-01

    Electron precipitation down to the atmosphere caused by wave-particle scattering in the magnetosphere contribute significantly to the enhancement of auroral ionospheric conductivity. Global MHD models that are incapable of capturing kinetic physics in the inner magnetosphere usually adopt MHD parameters to specify the precipitation flux to estimate auroral conductivity, hence losing self-consistency in the global circulation of the magnetosphere-ionosphere system. In this study we improve the coupling structure in global models by connecting the physics-based (wave-particle scattering) electron precipitation with the ionospheric electrodynamics and investigate the feedback effect on the magnetospheric dynamics. We use BATS-R-US coupled with a kinetic ring current model RAM-SCB that solves pitch angle dependent particle distributions to study the global circulation dynamics during the Jan 25-26, 2013 storm event. Following tail injections, we found enhanced precipitation number and energy fluxes of tens of keV electrons being scattered into loss cone due to interactions with enhanced chorus and hiss waves in the magnetosphere. This results in a more profound auroral conductance and larger electric field imposing on the plasma transport in the magnetosphere. We also compared our results with previous methods in specifying the auroral conductance, such as empirical relation used in Ridley et al. (2004). It is found that our physics-based method develops a larger convection electric field in the near-Earth region and therefore leads to a more intense ring current.

  4. Carbon cycle dynamics and solar activity embedded in a high-resolution 14C speleothem record from Belize, Central America

    NASA Astrophysics Data System (ADS)

    Lechleitner, Franziska A.; Breitenbach, Sebastian F. M.; McIntyre, Cameron; Asmerom, Yemane; Prufer, Keith M.; Polyak, Victor; Culleton, Brendan J.; Kennett, Douglas J.; Eglinton, Timothy I.; Baldini, James U. L.

    2015-04-01

    Speleothem 14C has recently emerged as a potentially powerful proxy for climate reconstruction. Several studies have highlighted the link between karst hydrology and speleothem 14C content, and a number of possible causes for this relationship have been proposed, such as dripwater flow dynamics in the karst and changes in soil organic matter (SOM) turnover time (e.g. Griffiths et al., 2012). Here we present a high resolution 14C record for a stalagmite (YOK-I) from Yok Balum cave in southern Belize, Central America. YOK-I grew continuously over the last 2000 years, and has been dated very precisely with the U-Th method (40 dates, mean uncertainty < 10 years). The excellent chronological control for this stalagmite allows us to calculate 14C activity (a14C) at the time of speleothem deposition (a14Cinit), as well as the dead carbon fraction (DCF), predominantly a measure of the reservoir effect introduced by limestone dissolution in the karst (Genty et al., 2001). Both records show striking similarities to atmospheric a14C (IntCal13) and reconstructions of solar activity and 14C production rate. We infer close coupling between cave environment and atmosphere, with minimal signal dampening, an observation supported by monitoring data (Ridley et al., in press). DCF fluctuates between approximately 10% and 16% over the entire record, with distinctly lower DCF values and higher a14Cinit during a period of reduced rainfall between ca. 700-1100 AD (linked to the Classic Maya Collapse). This behavior is consistent with observations made elsewhere, and suggests that DCF responds to karst hydrological variability, specifically open-closed system transitions. YOK-I a14Cinit typically lags atmospheric values by 10-100 cal years. A shorter lag appears to be linked to periods of drought, suggesting a response of SOM dynamics above the cave to rainfall reduction. Specifically, drought is inferred to lead to reduced bioproductivity and soil carbon turnover, lowering contributions

  5. Estimating at-sea mortality of marine turtles from stranding frequencies and drifter experiments.

    PubMed

    Koch, Volker; Peckham, Hoyt; Mancini, Agnese; Eguchi, Tomoharu

    2013-01-01

    Strandings of marine megafauna can provide valuable information on cause of death at sea. However, as stranding probabilities are usually very low and highly variable in space and time, interpreting the results can be challenging. We evaluated the magnitude and distribution of at-sea mortality of marine turtles along the Pacific coast of Baja California Sur, México during 2010-11, using a combination of counting stranded animals and drifter experiments. A total of 594 carcasses were found during the study period, with loggerhead (62%) and green turtles (31%) being the most common species. 87% of the strandings occurred in the southern Gulf of Ulloa, a known hotspot of loggerhead distribution in the Eastern Pacific. While only 1.8% of the deaths could be definitively attributed to bycatch (net marks, hooks), seasonal variation in stranding frequencies closely corresponded to the main fishing seasons. Estimated stranding probabilities from drifter experiments varied among sites and trials (0.05-0.8), implying that only a fraction of dead sea turtles can be observed at beaches. Total mortality estimates for 15-day periods around the floater trials were highest for PSL, a beach in the southern Gulf of Ulloa, ranging between 11 sea turtles in October 2011 to 107 in August 2010. Loggerhead turtles were the most numerous, followed by green and olive ridley turtles. Our study showed that drifter trials combined with beach monitoring can provide estimates for death at sea to measure the impact of small-scale fisheries that are notoriously difficult to monitor for by-catch. We also provided recommendations to improve the precision of the mortality estimates for future studies and highlight the importance of estimating impacts of small-scale fisheries on marine megafauna.

  6. Simulation of Theoretical Most-Extreme Geomagnetic Sudden Commencements

    NASA Astrophysics Data System (ADS)

    Welling, Daniel; Love, Jeffrey; Wiltberger, Michael; Rigler, Erin; Gombosi, Tamas

    2016-04-01

    We report results from a numerical simulation of geomagnetic sudden commencements driven by solar wind conditions given by theoretical-limit extreme coronal-mass ejections (CMEs) estimated by Tsurutani and Lakhina [2014]. The CME characteristics at Earth are a step function that jumps from typical quiet values to 2700 km/s flow speed and a magnetic field magnitude of 127 nT. These values are used to drive three coupled models: a global magnetohydrodynamic (MHD) magnetospheric model (BATS-R-US), a ring current model (the Rice Convection Model, RCM), and a height-integrated ionospheric electrodynamics model (the Ridley Ionosphere Model, RIM), all coupled together using the Space Weather Modeling Framework (SWMF). Additionally, simulations from the Lyon-Fedder-Mobarry MHD model are performed for comparison. The commencement is simulated with both purely northward and southward IMF orientations. Low-latitude ground-level geomagnetic variations, both B and dB/dt, are estimated in response to the storm sudden commencement. For a northward interplanetary magnetic field (IMF) storm, the combined models predict a maximum sudden commencement response, Dst-equivalent of +200 nT and a maximum local dB/dt of ~200nT/s. While this positive Dst response is driven mainly by magnetopause currents, complicated and dynamic Birkeland current patterns also develop, which drive the strong dB/dt responses at high latitude. For southward IMF conditions, erosion of dayside magnetic flux allows magnetopause currents to approach much closer to the Earth, leading to a stronger terrestrial response (Dst-equivalent of +250 nT). Further, high latitude signals from Region 1 Birkeland currents move to lower latitudes during the southward IMF case, increasing the risk to populated areas around the globe. Results inform fundamental understanding of solar-terrestrial interaction and benchmark estimates for induction hazards of interest to the electric-power grid industry.

  7. Risk analysis reveals global hotspots for marine debris ingestion by sea turtles.

    PubMed

    Schuyler, Qamar A; Wilcox, Chris; Townsend, Kathy A; Wedemeyer-Strombel, Kathryn R; Balazs, George; van Sebille, Erik; Hardesty, Britta Denise

    2016-02-01

    Plastic marine debris pollution is rapidly becoming one of the critical environmental concerns facing wildlife in the 21st century. Here we present a risk analysis for plastic ingestion by sea turtles on a global scale. We combined global marine plastic distributions based on ocean drifter data with sea turtle habitat maps to predict exposure levels to plastic pollution. Empirical data from necropsies of deceased animals were then utilised to assess the consequence of exposure to plastics. We modelled the risk (probability of debris ingestion) by incorporating exposure to debris and consequence of exposure, and included life history stage, species of sea turtle and date of stranding observation as possible additional explanatory factors. Life history stage is the best predictor of debris ingestion, but the best-fit model also incorporates encounter rates within a limited distance from stranding location, marine debris predictions specific to the date of the stranding study and turtle species. There is no difference in ingestion rates between stranded turtles vs. those caught as bycatch from fishing activity, suggesting that stranded animals are not a biased representation of debris ingestion rates in the background population. Oceanic life-stage sea turtles are at the highest risk of debris ingestion, and olive ridley turtles are the most at-risk species. The regions of highest risk to global sea turtle populations are off of the east coasts of the USA, Australia and South Africa; the east Indian Ocean, and Southeast Asia. Model results can be used to predict the number of sea turtles globally at risk of debris ingestion. Based on currently available data, initial calculations indicate that up to 52% of sea turtles may have ingested debris.

  8. Factors influencing survivorship of rehabilitating green sea turtles (Chelonia mydas) with fibropapillomatosis.

    PubMed

    Page-Karjian, Annie; Norton, Terry M; Krimer, Paula; Groner, Maya; Nelson, Steven E; Gottdenker, Nicole L

    2014-09-01

    Marine turtle fibropapillomatosis (FP) is a debilitating, infectious neoplastic disease that has reached epizootic proportions in several tropical and subtropical populations of green turtles (Chelonia mydas). FP represents an important health concern in sea turtle rehabilitation facilities. The objectives of this study were to describe the observed epidemiology, biology, and survival rates of turtles affected by FP (FP+ turtles) in a rehabilitation environment; to evaluate clinical parameters as predictors of survival in affected rehabilitating turtles; and to provide information about case progression scenarios and potential outcomes for FP+ sea turtle patients. A retrospective case series analysis was performed using the medical records of the Georgia Sea Turtle Center (GSTC), Jekyll Island, Georgia, USA, during 2009-2013. Information evaluated included signalment, morphometrics, presenting complaint, time to FP onset, tumor score (0-3), co-morbid conditions, diagnostic test results, therapeutic interventions, and case outcomes. Overall, FP was present in 27/362 (7.5%) of all sea turtles admitted to the GSTC for rehabilitation, either upon admittance or during their rehabilitation. Of these, 25 were green and 2 were Kemp's ridley turtles. Of 10 turtles that had only plaque-like FP lesions, 60% had natural tumor regression, all were released, and they were significantly more likely to survive than those with classic FP (P = 0.02 [0.27-0.75, 95% CI]). Turtles without ocular FP were eight times more likely to survive than those with ocular FP (odds ratio = 8.75, P = 0.032 [1.21-63.43, 95% CI]). Laser-mediated tumor removal surgery is the treatment of choice for FP+ patients at the GSTC; number of surgeries was not significantly related to case outcome.

  9. Tracing the biosynthetic source of essential amino acids in marine turtles using delta13C fingerprints.

    PubMed

    Arthur, Karen E; Kelez, Shaleyla; Larsen, Thomas; Choy, C Anela; Popp, Brian N

    2014-05-01

    Plants, bacteria, and fungi produce essential amino acids (EAAs) with distinctive patterns of delta13C values that can be used as naturally occurring fingerprints of biosynthetic origin of EAAs in a food web. Because animals cannot synthesize EAAs and must obtain them from food, their tissues reflect delta13C(EAA) patterns found in diet, but it is not known how microbes responsible for hindgut fermentation in some herbivores influence the delta13C values of EAAs in their hosts' tissues. We examined whether distinctive delta13C fingerprints of hindgut flora are evident in the tissues of green turtles (Chelonia mydas), which are known to be facultative hindgut fermenters. We determined delta13C(EAA) values in tissues of green turtles foraging herbivorously in neritic habitats of Hawaii and compared them with those from green, olive ridley, and loggerhead turtles foraging carnivorously in oceanic environments of the central and southeast Pacific Ocean. Results of multivariate statistical analysis revealed two distinct groups that could be distinguished based on unique delta13C(EAA) patterns. A three-end-member predictive linear discriminant model indicated that delta13C(EAA) fingerprints existed in the tissues of carnivorous turtles that resembled patterns found in microalgae, which form the base of an oceanic food web, whereas herbivorous turtles derive EAAs from a bacterial or seagrass source. This study demonstrates the capacity for delta13C fingerprinting to establish the biosynthetic origin of EAAs in higher consumers, and that marine turtles foraging on macroalgal diets appear to receive nutritional supplementation from bacterial symbionts in their digestive system.

  10. Hot Oxygen Corona in Mars' Upper Thermosphere and Exosphere: A Comparison of Results Using the MGITM and MTGCM

    NASA Astrophysics Data System (ADS)

    Lee, Y.; Combi, M. R.; Tenishev, V.; Bougher, S. W.

    2013-12-01

    The evaluation of the global atmospheric loss rate and the water inventory allows a better understanding of the physics that drives the current state of the Martian atmosphere. The production of energetic particles in Mars's upper thermosphere and exosphere results in the formation of the hot corona, where the most of the escape of neutral atoms occur. In this study, we evaluate the oxygen atom inventory by studying the production and distribution of energetic oxygen. Dissociative recombination (DR) of O2+ ion is the dominant source of the production of hot atomic oxygen, which occurs mostly deep in the dayside of the thermosphere, and the most important reaction in the Martian atmosphere. For the computation, we adopt the latest available branching ratios and appropriate choice of the rate coefficient. We carry out a study of the seasonal and solar cycle variability on the hot oxygen corona. To describe self-consistently the upper thermosphere and exosphere, a combination of our 3D Direct Simulation Monte Carlo (DSMC) model [Valeille, A., Combi, M., Bougher, S., Tenishev, V., Nagy, A., 2009. J. Geophys. Res. 114, E11006. doi:10.1029/2009JE003389] and the 3D Mars Thermosphere General Circulation Model (MTGCM) [Bougher, S. W., Bell, J. M., Murphy, J. R., Lopez-Valverde, M. A., Withers, P. G., 2006. Geophys. Res. Lett. 32, doi: 10.1029/2005GL024059. L02203] is used. The simulated results using MTGCM as the thermosphere / ionosphere input are compared with those using Mars Global Ionosphere Thermosphere Model (MGITM) [Bougher, S. W., Pawlowski, D., Bell, J., Nelli, S., McDunn, T., Murphy, J., Chizek, M., and Ridley, A., 2013. in final preparation], the newly developed 3D Martian atmosphere model. In this comparison, we investigate the differences in the results and the impacts of the recent development of the atmosphere model on the hot oxygen corona. This study also compares our computed total oxygen escape rate with those from other recent exosphere model studies.

  11. Indigenous Cases of Leprosy (Hansen's Disease) in Southern Mississippi.

    PubMed

    Marcos, Luis A; Dobbs, Thomas; Walker, Sue; Waller, William; Stryjewska, Barbara M

    2015-07-01

    Hansen's disease or leprosy is a chronic infection of the skin and peripheral nerves caused by Mycobacterium leprae. In the U.S., leprosy is mainly reported in immigrants, but indigenous leprosy cases have been also reported in this country, especially in semitropical southern states (i.e., Texas, Louisiana). The objective of this series of cases is to describe indigenous leprosy cases reported in southern Mississippi (MS) during the period 2012-2014. Information was collected from medical records at Hattiesburg Clinic and the MS Department of Health. Four cases were reported during the period of study (3 Caucasian males, 1 African-American woman). Non of visited endemic leprosy country. The age ranged from 60 to 83 years (median: 75.5 years). Of the four cases, three presented with a slowly progressive erythematous rash disseminated mainly on the thorax and abdomen, with a lesser degree on the extremities. The time between onset of rash until the diagnosis ranged from 5 to 16 months (median: 7 months). Only one case had direct contact with armadillos (blood exposure). Non of these patients had a history of immunosuppression. The most common symptoms were neuropathic pain (n=2), generalized pruritus (n=2) and loss of sensation in extremities (n=2). One case had severe peripheral neuropathy with muscle weakness, atrophy in left arm, and wasting on left hand. Skin biopsies showed diffuse granulomatous infiltrate with foamy histiocytes along with acid fast bacilli by Fite stain. By Ridley-Jopling classification system, three cases were diagnosis as lepromatous leprosy, and one, borderline lepromatous. Treatment included clofazimine, dapsone and rifampin that was offered free of charge by the National Hansen's Diseases Program, Baton Rouge, L.A. One patient did not tolerate therapy. In conclusion, a slowly progressive disseminated erythematous skin rash on the trunk should raise suspicion for leprosy in the elderly population in south MS.

  12. Vibrio mimicus diarrhea following ingestion of raw turtle eggs.

    PubMed Central

    Campos, E; Bolaños, H; Acuña, M T; Díaz, G; Matamoros, M C; Raventós, H; Sánchez, L M; Sánchez, O; Barquero, C

    1996-01-01

    Clinical and epidemiological characteristics of diarrhea associated with Vibrio mimicus were identified in 33 hospitalized patients referred to the Costa Rican National Diagnostic Laboratory Network between 1991 and 1994. The relevant symptoms presented by patients included abundant watery diarrhea, vomiting, and severe dehydration that required intravenous Dhaka solution in 83% of patients but not fever. Seroconversion against V. mimicus was demonstrated in four patients, from whom acute- and convalescent-phase sera were obtained. Those sera did not show cross-reaction when tested against Vibrio cholerae O1 strain VC-12. All the V. mimicus isolates from these cases produced cholera toxin (CT) and were susceptible to commonly used antibiotics. Attempts to isolate this bacterium from stool samples of 127 healthy persons were not successful. Consumption of raw turtle eggs was recalled by 11 of the 19 (58%) individuals interviewed. All but two V. mimicus diarrheal cases were sporadic. These two had a history of a common source of turtle (Lepidochelys olivacea) eggs for consumption, and V. mimicus was isolated from eggs from the same source (a local market). Among the strains, variations in the antimicrobial susceptibility pattern were observed. None of the strains recovered from market turtle eggs nor the four isolates from river water showed CT production. Further efforts to demonstrate the presence of CT-producing V. mimicus strains in turtle eggs were made. Successful results were obtained when nest eggs were tested. In this case, it was possible to isolate CT- and non-CT-producing strains, even from the same egg. For CT detection we used PCR, enzyme-linked immunosorbent assay (ELISA), and Y-1 cell assay, obtaining a 100% correlation between ELISA and PCR results. Primers Col-1 and Col-2, originally described as specific for the V. cholerae O1 ctxA gene, also amplified a 302-bp segment with an identical restriction map from V. mimicus. These results have important

  13. Metastable Phases in Ice Clouds

    NASA Astrophysics Data System (ADS)

    Weiss, Fabian; Baloh, Philipp; Kubel, Frank; Hoelzel, Markus; Parker, Stewart; Grothe, Hinrich

    2014-05-01

    Polar Stratospheric Clouds and Cirrus Clouds contain both, pure water ice and phases of nitric acid hydrates. Preferentially for the latter, the thermodynamically stable phases have intensively been investigated in the past (e.g. nitric acid trihydrate, beta-NAT). As shown by Peter et al. [1] the water activity inside clouds is higher than expected, which might be explained by the presence of metastable stable phases (e.g. cubic ice). However, also metastable nitric acid hydrates might be important due to the inherent non-equilibrium freezing conditions in the upper atmosphere. The delta ice theory of Gao et al. [2] presents a model approach to solve this problem by involving both metastable ice and NAT as well. So it is of high interest to investigate the metastable phase of NAT (i.e. alpha-NAT), the structure of which was unknown up to the presence. In our laboratory a production procedure for metastable alpha-NAT has been developed, which gives access to neutron diffraction and X-ray diffraction measurements, where sample quantities of several Gramm are required. The diffraction techniques were used to solve the unknown crystalline structure of metastable alpha-NAT, which in turn allows the calculation of the vibrational spectra, which have also been recorded by us in the past. Rerefences [1] Peter, T., C. Marcolli, P. Spichtinger, T. Corti, M. B. Baker, and T. Koop. When dry air is too humid. Science, 314:1399-1402, 2006. [2] Gao, R., P. Popp, D. Fahey, T. Marcy, R. L. Herman, E. Weinstock, D. Baumgardener, T. Garrett, K. Rosenlof, T. Thompson, T. P. Bui, B. Ridley, S. C. Wofsy, O. B. Toon, M. Tolbert, B. Kärcher, Th. Peter, P. K. Hudson, A. Weinheimer, and A. Heymsfield. Evidence That Nitric Acid Increases Relative Humidity in Low-Temperature Cirrus Clouds, Science, 303:516-520, 2004. [3] Tizek, H., E. Knözinger, and H. Grothe. Formation and phase distribution of nitric acid hydrates in the mole fraction range xHNO3<0.25: A combined XRD and IR study, PCCP, 6

  14. Evaluation and Validation of Simulated CYGNSS Winds over Large Range of Tropical Cyclones

    NASA Astrophysics Data System (ADS)

    Jelenak, Zorana; Chang, Paul; Soisuvarn, Seubson; Said, Faozi

    2015-04-01

    examined and validated against project science requirements document. The improved understanding of measurement and algorithm performances, derived from these analyses, led us to develop new quality flagging scheme with a goal of achieving a more robust wind product. The new flagging scheme has been proposed and implemented in final validation statistics. A summary of the analyses of these simulated data and flagging algorithm will be presented and discussed. References: [1] Ruf, C.S.; Gleason, S.; Jelenak, Z.; Katzberg, S.; Ridley, A.; Rose, R.; Scherrer, J.; Zavorotny, V. : The CYGNSS nanosatellite constellation hurricane mission; IEEE International Geoscience and Remote Sensing Symposium Proceedings, pp 214-216; July 2012 [2] Clarizia, M.P.; Ruf, C.S.; Jales, P.; Gommenginger, C.; Spaceborne GNSS-R minimum variance wind speed estimator; IEEE Transactions on Geoscience and Remote Sensing, pp 6829-6843; February 2014

  15. Two way coupling RAM-SCB to the space weather modeling framework

    SciTech Connect

    Welling, Daniel T; Jordanova, Vania K; Zaharia, Sorin G; Toth, Gabor

    2010-12-03

    The Ring current Atmosphere interaction Model with Self-Consistently calculated 3D Magnetic field (RAM-SCB) has been used to successfully study inner magnetosphere dynamics during different solar wind and magnetosphere conditions. Recently, one way coupling of RAM-SCB with the Space Weather Modeling Framework (SWMF) has been achieved to replace all data or empirical inputs with those obtained through first-principles-based codes: magnetic field and plasma flux outer boundary conditions are provided by the Block Adaptive Tree Solar wind Roe-type Upwind Scheme (BATS-R-US) MHO code, convection electric field is provided by the Ridley Ionosphere Model (RIM), and ion composition is provided by the Polar Wind Outflow Model (PWOM) combined with a multi-species MHO approach. These advances, though creating a powerful inner magnetosphere virtual laboratory, neglect the important mechanisms through which the ring current feeds back into the whole system, primarily the stretching of the magnetic field lines and shielding of the convection electric field through strong region two Field Aligned Currents (FACs). In turn, changing the magnetosphere in this way changes the evolution of the ring current. To address this shortcoming, the coupling has been expanded to include feedback from RAM-SCB to the other coupled codes: region two FACs are returned to the RIM while total plasma pressure is used to nudge the MHO solution towards the RAMSCB values. The impacts of the two way coupling are evaluated on three levels: the global magnetospheric level, focusing on the impact on the ionosphere and the shape of the magnetosphere, the regional level, examining the impact on the development of the ring current in terms of energy density, anisotropy, and plasma distribution, and the local level to compare the new results to in-situ measurements of magnetic and electric field and plasma. The results will also be compared to past simulations using the one way coupling and no coupling

  16. Comparison of functional aspects of the coagulation cascade in human and sea turtle plasmas.

    PubMed

    Soslau, Gerald; Wallace, Bryan; Vicente, Catherine; Goldenberg, Seth J; Tupis, Todd; Spotila, James; George, Robert; Paladino, Frank; Whitaker, Brent; Violetta, Gary; Piedra, Rotney

    2004-08-01

    Functional hemostatic pathways are critical for the survival of all vertebrates and have been evolving for more than 400 million years. The overwhelming majority of studies of hemostasis in vertebrates have focused on mammals with very sparse attention paid to reptiles. There have been virtually no studies of the coagulation pathway in sea turtles whose ancestors date back to the Jurassic period. Sea turtles are often exposed to rapidly altered environmental conditions during diving periods. This may reduce their blood pH during prolonged hypoxic dives. This report demonstrates that five species of turtles possess only one branch of the mammalian coagulation pathway, the extrinsic pathway. Mixing studies of turtle plasmas with human factor-deficient plasmas indicate that the intrinsic pathway factors VIII and IX are present in turtle plasma. These two factors may play a significant role in supporting the extrinsic pathway by feedback loops. The intrinsic factors, XI and XII are not detected which would account for the inability of reagents to induce coagulation via the intrinsic pathway in vitro. The analysis of two turtle factors, factor II (prothrombin) and factor X, demonstrates that they are antigenically/functionally similar to the corresponding human factors. The turtle coagulation pathway responds differentially to both pH and temperature relative to each turtle species and relative to human samples. The coagulation time (prothrombin time) increases as the temperature decreases between 37 and 15 degrees C. The increased time follows a linear relationship, with similar slopes for loggerhead, Kemps ridley and hawksbill turtles as well as for human samples. Leatherback turtle samples show a dramatic nonlinear increased time below 23 degrees C, and green turtle sample responses were similar but less dramatic. All samples also showed increased prothrombin times as the pH decreased from 7.8 to 6.4, except for three turtle species. The prothrombin times decreased

  17. Measurements of HCl and HNO3 with the new research aircraft HALO - Quantification of the stratospheric contribution to the O3 and HNO3 budget in the UT/LS

    NASA Astrophysics Data System (ADS)

    Jurkat, Tina; Kaufmann, Stefan; Voigt, Christiane; Zahn, Andreas; Schlager, Hans; Engel, Andreas; Bönisch, Harald; Dörnbrack, Andreas

    2013-04-01

    data from remote sensing instruments. Further, they will help to validate global chemistry-climate models to gain a better understanding of the trace gas distribution in the UT/LS. Marcy, T. P., Fahey, D. W., Gao, R. S., Popp, P. J., Richard, E. C., Thompson, T. L., Rosenlof, K. H., Ray, E. A., Salawitch, R. J., Atherton, C. S., Bergmann, D. J., Ridley, B. A., Weinheimer, A. J., Loewenstein, M., Weinstock, E. M., and Mahoney, M. J.: Quantifying stratospheric ozone in the upper troposphere with in situ measurements of HCl, Science, 304, 261-265, 2004.

  18. EDITORIAL: The Eye and The Chip 2008 The Eye and The Chip 2008

    NASA Astrophysics Data System (ADS)

    Rizzo, Joseph F.; O'Malley, Edward R.; Hessburg, Philip C.

    2009-06-01

    Over the course of the past decade, The Eye and The Chip world congress on visual neuro-prosthetic devices has become a premier meeting for those who believe that 'artificial' vision will one day be used to improve the quality of life of visually impaired patients. Although substantial progress has been made, there are numerous unresolved issues, like the preferred methods for wireless communication, placement of devices, and materials and design among others. The Eye and The Chip meeting of 2008, held in Detroit on 12-14 June 2008, provided important new information about these and other important topics, and thus served to advance this field of scientific research. From a research seedling a decade ago to the crowd of superb presentations in Detroit last June, a very real sense of justifiable optimism has developed. The prospects of artificial vision are no longer remote. Many of the researchers expressed confidence that implantable devices will provide the hoped-for level of vision to justify their widespread use in the future. The often dramatic successes of cochlear implants continues to provide credence that artificial stimulation of nerve tissue is a plausible strategy to restore vision. The Eye and The Chip 2008 attracted researchers from four continents (North America, Europe, Asia and Australia). The meeting also benefited from the attendance and presentations by representatives of the FDA, who have been present for all The Eye and The Chip meetings. The 2008 meeting was also enhanced by the inclusion of a new and related scientific field that shares the goal of restoring vision to the blind—the field of molecular restoration of retinal function by insertion of channelrhodopsin. Just as the field of ophthalmology went from Ridley's primitive intraocular lens replacement to implants useful in virtually every cataract patient in one surgeon's clinical lifetime, the field of retinal prostheses seems to be following a very similar trajectory. Likewise, the

  19. Development of the Non-Hydrostatic Jupiter Global Ionosphere Thermosphere Model (J-GITM): Status and Current Simulations

    NASA Astrophysics Data System (ADS)

    Bougher, Stephen; Ridley, Aaron; Majeed, Tariq; Waite, J. Hunter; Gladstone, Randy; Bell, Jared

    2016-07-01

    The primary objectives for development and validation of a new 3-D non-hydrostatic model of Jupiter's upper atmosphere is to improve our understanding of Jupiter's thermosphere-ionosphere-magnetosphere system and to provide a global context within which to analyze the data retrieved from the new JUNO mission. The new J-GITM model presently incorporates the progress made on the previous Jupiter-TGCM code (i.e. key parameterizations, ion-neutral chemistry, IR cooling) while also employing the non-hydrostatic numerical core of the Earth Global Ionosphere-Thermosphere Model (GITM). The GITM numerical framework has been successfully applied to Earth, Mars, and Titan (see Ridley et al. [2006], Bougher et al. [2015], Bell [2008, 2010]). Moreover, it has been shown to simulate the effects of strong, localized heat sources (such as joule heating and auroral heating) more accurately than strictly hydrostatic GCMs (Deng et al. [2007, 2008]). Thus far, in the J-GITM model development and testing, model capability has been progressively augmented to capture the neutral composition (e.g. H, H2, He major species), 3-component neutral winds, and thermal structure, as well as the ion composition (H3+, H2+, and H+ among others) above 250 km. Presently, J-GITM: (a) provides an interactive calculation for auroral particle precipitation (i.e. heating, ionization), an improvement over the static formulation used previously in the J-TGCM (Bougher et al., 2005; Majeed et al., 2005, 2009, 2015); (b) self-consistently calculates an ionosphere using updated ion-neutral chemistry, ion dynamics, and electron transport; (c) simulates the chemistry that forms key hydrocarbons at the base of the thermosphere, focusing on CH4, C2H2, and C2H6; (d) allows the production of H3+, CH4, C2H2, and C2H6 to modify the global thermal balance of Jupiter through their non-LTE radiative cooling; (e) provides a calculation of H2 vibrational chemistry to regulate H+ densities; and (f) uses the improved

  20. Inner-sphere complexation of cations at the rutile-water interface: A concise surface structural interpretation with the CD and MUSIC model

    NASA Astrophysics Data System (ADS)

    Ridley, Moira K.; Hiemstra, Tjisse; van Riemsdijk, Willem H.; Machesky, Michael L.

    2009-04-01

    Acid-base reactivity and ion-interaction between mineral surfaces and aqueous solutions is most frequently investigated at the macroscopic scale as a function of pH. Experimental data are then rationalized by a variety of surface complexation models. These models are thermodynamically based which in principle does not require a molecular picture. The models are typically calibrated to relatively simple solid-electrolyte solution pairs and may provide poor descriptions of complex multi-component mineral-aqueous solutions, including those found in natural environments. Surface complexation models may be improved by incorporating molecular-scale surface structural information to constrain the modeling efforts. Here, we apply a concise, molecularly-constrained surface complexation model to a diverse suite of surface titration data for rutile and thereby begin to address the complexity of multi-component systems. Primary surface charging curves in NaCl, KCl, and RbCl electrolyte media were fit simultaneously using a charge distribution (CD) and multisite complexation (MUSIC) model [Hiemstra T. and Van Riemsdijk W. H. (1996) A surface structural approach to ion adsorption: the charge distribution (CD) model. J. Colloid Interf. Sci. 179, 488-508], coupled with a Basic Stern layer description of the electric double layer. In addition, data for the specific interaction of Ca 2+ and Sr 2+ with rutile, in NaCl and RbCl media, were modeled. In recent developments, spectroscopy, quantum calculations, and molecular simulations have shown that electrolyte and divalent cations are principally adsorbed in various inner-sphere configurations on the rutile 1 1 0 surface [Zhang Z., Fenter P., Cheng L., Sturchio N. C., Bedzyk M. J., Předota M., Bandura A., Kubicki J., Lvov S. N., Cummings P. T., Chialvo A. A., Ridley M. K., Bénézeth P., Anovitz L., Palmer D. A., Machesky M. L. and Wesolowski D. J. (2004) Ion adsorption at the rutile-water interface: linking molecular and macroscopic

  1. Sinkhole flooding in Murfreesboro, Rutherford County, Tennessee, 2001-02

    USGS Publications Warehouse

    Bradley, Michael W.; Hileman, Gregg Edward

    2006-01-01

    The U.S. Geological Survey, in cooperation with the City of Murfreesboro, Tennessee, conducted an investigation from January 2001 through April 2002 to delineate sinkholes and sinkhole watersheds in the Murfreesboro area and to characterize the hydrologic response of sinkholes to major rainfall events. Terrain analysis was used to define sinkholes and delineate the sinkhole drainage areas. Flooding in 78 sinkholes in three focus areas was identified and tracked using aerial photography following three major storms in February 2001, January 2002, and March 2002. The three focus areas are located to the east, north, and northwest of Murfreesboro and are underlain primarily by the Ridley Limestone with some outcrops of the underlying Pierce Limestone. The observed sinkhole flooding is controlled by water inflow, water outflow, and the degree of the hydraulic connection (connectivity) to a ground-water conduit system. The observed sinkholes in the focus areas are grouped into three categories based on the sinkhole morphology and the connectivity to the ground-water system as indicated by their response to flooding. The three types of sinkholes described for these focus areas are pan sinkholes with low connectivity, deep sinkholes with high connectivity, and deep sinkholes with low connectivity to the ground-water conduit system. Shallow, broad pan sinkholes flood as water inflow from a storm inundates the depression at land surface. Water overflow from one pan sinkhole can flow downgradient and become inflow to a sinkhole at a lower altitude. Land-surface modifications that direct more water into a pan sinkhole could increase peak-flood altitudes and extend flood durations. Land-surface modifications that increase the outflow by overland drainage could decrease the flood durations. Road construction or alterations that reduce flow within or between pan sinkholes could result in increased flood durations. Flood levels and durations in the deeper sinkholes observed in

  2. Improvements in the use of aquatic herbicides and establishment of future research directions

    USGS Publications Warehouse

    Getsinger, K.D.; Netherland, M.D.; Grue, C.E.; Koschnick, T.J.

    2008-01-01

    Peer-reviewed literature over the past 20 years identifies significant changes and improvements in chemical control strategies used to manage nuisance submersed vegetation. The invasive exotic plants hydrilla (Hydrilla verticillata L.f. Royle) and Eurasian watermilfoil (Myriophyllum spicatum L.) continue to spread and remain the plant species of greatest concern for aquatic resource managers at the national scale. Emerging exotic weeds of regional concern such as egeria (Egeria densa Planch.), curlyleaf pondweed (Potamogeton crispus L.), and hygrophila (Hygrophila polysperma (Roxb.) T. Anders), as well as native plants such as variable watermilfoil (Myriophyllum heterophyllum Michx), and cabomba (Cabomba caroliniana Gray) are invasive outside their home ranges. In addition, there is always the threat of new plant introductions such as African elodea (Lagarosiphon major (Ridley) Moss) or narrow-leaf anacharis (Egeria najas Planchon). The registration of the bleaching herbicide fluridone in the mid 1980s for whole-lake and large-scale management stimulated numerous lines of research involving reduction of use rates, plant selectivity, residue monitoring, and impacts on fisheries. In addition to numerous advances, the specificity of fluridone for a single plant enzyme led to the first documented case of herbicide resistance in aquatic plant management. The resistance of hydrilla to fluridone has stimulated a renewed interest by industry and others in the registration of alternative modes of action for aquatic use. These newer chemistries tend to be enzyme-specific compounds with favorable non-target toxicity profiles. Registration efforts have been facilitated by increased cooperation between key federal government agencies that have aquatic weed control and research responsibilities, and regulators within the U.S. Environmental Protection Agency (USEPA). We reviewed past and current research efforts to identify areas in need of further investigation and to establish

  3. inner-sphere complexation of cations at the rutile-water interface: A concise surface structural interpretation with the CD and MUSIC model

    SciTech Connect

    Ridley, Mora K.; Hiemstra, T; Van Riemsdijk, Willem H.; Machesky, Michael L.

    2009-01-01

    Acid base reactivity and ion-interaction between mineral surfaces and aqueous solutions is most frequently investigated at the macroscopic scale as a function of pH. Experimental data are then rationalized by a variety of surface complexation models. These models are thermodynamically based which in principle does not require a molecular picture. The models are typically calibrated to relatively simple solid-electrolyte solution pairs and may provide poor descriptions of complex multicomponent mineral aqueous solutions, including those found in natural environments. Surface complexation models may be improved by incorporating molecular-scale surface structural information to constrain the modeling efforts. Here, we apply a concise, molecularly-constrained surface complexation model to a diverse suite of surface titration data for rutile and thereby begin to address the complexity of multi-component systems. Primary surface charging curves in NaCl, KCl, and RbCl electrolyte media were fit simultaneously using a charge distribution (CD) and multisite complexation (MUSIC) model [Hiemstra T. and Van Riemsdijk W. H. (1996) A surface structural approach to ion adsorption: the charge distribution (CD) model. J. Colloid Interf. Sci. 179, 488 508], coupled with a Basic Stern layer description of the electric double layer. In addition, data for the specific interaction of Ca2+ and Sr2+ with rutile, in NaCl and RbCl media, were modeled. In recent developments, spectroscopy, quantum calculations, and molecular simulations have shown that electrolyte and divalent cations are principally adsorbed in various inner-sphere configurations on the rutile 110 surface [Zhang Z., Fenter P., Cheng L., Sturchio N. C., Bedzyk M. J., Pr edota M., Bandura A., Kubicki J., Lvov S. N., Cummings P. T., Chialvo A. A., Ridley M. K., Be ne zeth P., Anovitz L., Palmer D. A., Machesky M. L. and Wesolowski D. J. (2004) Ion adsorption at the rutile water interface: linking molecular and macroscopic

  4. Radiogenic isotope evidence for transatlantic atmospheric dust transport

    NASA Astrophysics Data System (ADS)

    Kumar, Ashwini; Abouchami, Wafa; Garrison, Virginia H.; Galer, Stephen J. G.; Andreae, Meinrat O.

    2013-04-01

    source origin. These results identify an African source signal, in aerosols from the Virgin Islands and Tobago collected during African dusts incursion, and thus provides evidence for transatlantic dust transport during the spring/summer season. This, in turn, is entirely consistent with 7-day back-trajectory analysis at these locations as well as recent seasonal AOD maps [8]. [1] Prospero et al. (1970) Earth Planet. Sci. Lett. 9, 287-293. [2] Swap et al. (1992) Tellus 44, 133-149. [3] Koren et al. (2006) Environ. Res. Lett. 1, 014005. [4] Ben-Ami et al. (2010) Atmos. Chem. Phys. 10, 7533-7544. [5] Duce & Tindale (1991) Lim Ocean., 36, 1715-1726. [6] Bollhöfer & Rosman (2000) Geochim. Cosmochim. Acta 64, 3251-3262. [7] Abouchami et al. (in prep.) [8] Ridley et al. (2012) J. Geophys. Res. 117, D02202.

  5. Copper isotope fractionation during its interaction with soil and aquatic microorganisms and metal oxy(hydr)oxides: Possible structural control

    NASA Astrophysics Data System (ADS)

    Pokrovsky, O. S.; Viers, J.; Emnova, E. E.; Kompantseva, E. I.; Freydier, R.

    2008-04-01

    Brantley S. (2005) Cu isotopic fractionation in the supergene environment with and without bacteria. Geochim. Cosmochim. Acta69, 5233-5246] and Balistrieri et al. [Balistrieri L. S., Borrok D. M., Wanty R. B. and Ridley W. I. (2008) Fractionation of Cu and Zn isotopes during adsorption onto amorhous Fe(III) oxyhydroxide: experimental mixing of acid rock drainage and ambient river water. Geochim. Cosmochim. Acta72, 311-328] who reported heavy Cu isotope enrichment onto amorphous ferric oxyhydroxide and on metal hydroxide precipitates on the external membranes of Fe-oxidizing bacteria, respectively. Although measured isotopic fractionation does not correlate with the relative thermodynamic stability of surface complexes, it can be related to their structures as found with available EXAFS data. Indeed, strong, bidentate, inner-sphere complexes presented by tetrahedrally coordinated Cu on metal oxide surfaces are likely to result in enrichment of the heavy isotope on the surface compared to aqueous solution. The outer-sphere, monodentate complex, which is likely to form between Cu 2+ and surface phosphoryl groups of bacteria in acidic solutions, has a higher number of neighbors and longer bond distances compared to inner-sphere bidentate complexes with carboxyl groups formed on bacterial and diatom surfaces in circumneutral solutions. As a result, in acidic solution, light isotopes become more enriched on bacterial surfaces (as opposed to the surrounding aqueous medium) than they do in neutral solution. Overall, the results of the present study demonstrate important isotopic fractionation of copper in both organic and inorganic systems and provide a firm basis for using Cu isotopes for tracing metal transport in earth-surface aquatic systems. It follows that both adsorption on oxides in a wide range of pH values and adsorption on bacteria in acidic solutions are capable of producing a significant (up to 2.5-3‰ (±0.1-0.15‰)) isotopic offset. At the same time, Cu

  6. Nature of the Venus thermosphere derived from satellite drag measurements (solicited paper)

    NASA Astrophysics Data System (ADS)

    Keating, G.; Theriot, M.; Bougher, S.

    2008-09-01

    -4197, 1992. [3] Keating, G.M.; Taylor, F.W.; Nicholson, J. V. II; and Hinson, E.W. : Short-Term Cyclic Variations and Diurnal Variations of the Venus Upper Atmosphere, Science, Vol. 205, No. 4401, 62-64, July 6, 1979. [4] Bougher, S. W.; Dickinson, R. E.; Ridley, E. C.; Roble, R. G.; Nagy, A. F.; and Cravens, T. E.: Venus mesosphere and thermosphere, II, Global circulation, temperature, and density variations, Icarus, Vol. 68, 284-312, 1986. [5] Keating, G. M. et al.: Evidence of Long-Term Global Decline in the Earth's Thermospheric Densities Apparently Related to Anthropogenic Effects, Geophysical Research Letters, Vol. 27, No. 10, 1522-1526, 2000. [6] Keating, G. M. et al.: Models of Venus Neutral Upper Atmosphere Structure and Composition: The Venus International Reference Atmosphere (Edited by A. L. Kliore, V. I. Moros, and G. M. Keating) Advances in Space Research, Vol. 5, No. 11, 117-171,1985. [7] Keating, G. M.; Hsu, N.C., and Lyu, J.: Improved Thermospheric Model for the Venus International Reference Atmosphere, Proceedings of the 31st Scientific Assembly of COSPAR, Birmingham, England, 139, 1996 (Invited) [8] Keating, G. M. and Hsu, N. C.: The Venus Atmospheric Response to Solar Cycle Variations, Geophysical Research Letters, Vol. 20, 2751-2754, 1993. [9] Keating, G.M. et al: Future drag measurements from Venus Express. Adv