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Ascension Island as a mid-Atlantic developmental habitat for juvenile hawksbill turtles

  • Sam B. Weber (a1) (a2), Nicola Weber (a1) (a2), Brendan J. Godley (a2), Tara Pelembe (a3), Stedson Stroud (a1), Natasha Williams (a1) and Annette C. Broderick (a2)...
Abstract

Ascension Island in the South Atlantic Ocean is renowned for its globally-important nesting population of green turtles (Chelonia mydas) that has been the subject of long-term research. By comparison, very little is known about the apparently small population of hawksbill turtles (Eretmochelys imbricata) that have been recorded in its waters, thousands of kilometres from known nesting beaches. Here, we collate 10 years of in-water tagging data, opportunistic public sighting records and underwater observations to provide a baseline for future research, and present preliminary data on habitat use derived from two individuals fitted with GPS transmitters. Although public sightings were inevitably biased towards popular recreation areas, the resulting distribution suggests that hawksbill turtles occur year round in Ascension Island's waters along the entire 65 km of coastline. Hawksbills were observed feeding on benthic algae and encrusting sponges, and were frequently seen scavenging on fish discards around the Island's pier at night aided by anthropogenic lighting. Between 2003 and 2013, 35 turtles were captured, measured, tagged and then released. Curved carapace lengths ranged from 33.5 to 85 cm (mean = 48.8 cm) indicating that most (if not all) individuals encountered around Ascension are post-pelagic juveniles. Four individuals were recaptured at least once giving a mean minimum residence time of 4.2 yr (range: 2.8–7.3 yr) and a mean growth rate of 2.8 cm yr−1. Turtles fitted with Fastloc™ GPS devices remained at Ascension Island for the duration of the study (>90 days) and occupied restricted home ranges with an average area of 2.5 km2 and an average ‘core use area’ (50% utilization distribution) of 0.05 km2. Together, these results suggest that Ascension Island serves as a mid-Atlantic developmental habitat for benthic-feeding, juvenile hawksbill turtles on extended oceanic migrations before recruiting to their adult foraging grounds, likely to be located in Brazil or tropical West Africa.

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Copyright
Corresponding author
Correspondence should be addressed to: S.B. Weber, Ascension Island Government Conservation Department, Georgetown, Ascension Island, South Atlantic Ocean, ASCN 1ZZ email: sam.weber@ascension.gov.ac
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These authors made equal contributions to the manuscript.

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References
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Ashmole, N.P. and Ashmole, M.J. (2000) St Helena and Ascension Island: a natural history. Oswestry: Anthony Nelson.
Barceló, C., Domingo, A., Miller, P., Ortega, L., Giffoni, B., Sales, G., McNaughton, L., Marcovaldi, M., Heppell, S. and Swimmer, Y. (2013) High-use areas, seasonal movements and dive patterns of juvenile loggerhead sea turtles in the Southwestern Atlantic Ocean. Marine Ecology Progress Series 479, 235250.
Bellini, C. (1996) Reproduction and feeding of marine turtles in the Fernando de Noronha Archipelago, Brazil. Marine Turtle Newsletter 74, 1213.
Benhamou, S. and Cornelis, D. (2010) Incorporating movement behavior and barriers to improve kernel home range space use estimates. Journal of Wildlife Management 74, 13531360.
Berube, M.D., Dunbar, S.G., Rützler, K. and Hayes, W.K. (2012) Home range and foraging ecology of juvenile Hawksbill sea turtles (Eretmochelys imbricata) on inshore reefs of Honduras. Chelonian Conservation and Biology 11, 3343.
Blumenthal, J.M., Abreu-Grobois, F.A., Austin, T.J., Broderick, A.C., Bruford, M.W., Coyne, M.S., Ebanks-Petrie, G., Formia, A., Meylan, P.A., Meylan, A.B. and Godley, B.J. (2009b) Turtle groups or turtle soup: dispersal patterns of hawksbill turtles in the Caribbean. Molecular Ecology 18, 48414853.
Blumenthal, J.M., Austin, T.J., Bell, C.D.L., Bothwell, J.B., Broderick, A.C., Ebanks-Petrie, G., Gibb, J.A., Luke, K.E., Olynik, J.R. and Orr, M.F. (2009a) Ecology of hawksbill turtles, Eretmochelys imbricata, on a western Caribbean foraging ground. Chelonian Conservation and Biology 8, 110.
Bolten, A.B. (2003) Variation in sea turtle life history patterns: neritic vs. oceanic developmental stages. In Lutz, P.L., Musick, J.A. and Wyneken, J. (eds) The biology of sea turtles. Volume 2. Boca Raton, FL: CRC Press, pp. 243258.
Broderick, A.C., Frauenstein, R., Glen, F., Hays, G.C., Jackson, A.L., Pelembe, T., Ruxton, G.D. and Godley, B.J. (2006) Are green turtles globally endangered? Global Ecology and Biogeography 15, 2126.
Burt, W.H. (1943) Territoriality and home range concepts as applied to mammals. Journal of Mammalogy 24, 346352.
Calenge, C. (2006) The package adehabitat for the R software: a tool for the analysis of space and habitat use by animals. Ecological Modelling 197, 516519.
Carr, A.F. (1980) Some problems of sea turtle ecology. American Zoologist 20, 489498.
Carrión-Cortez, J., Canales-Cerro, C., Arauz, R. and Riosmena-Rodríguez, R. (2013) Habitat use and diet of juvenile Eastern Pacific hawksbill turtles (Eretmochelys imbricata) in the North Pacific Coast of Costa Rica. Chelonian Conservation and Biology 12, 235245.
Chaloupka, M.Y. and Limpus, C.J. (1997) Robust statistical modelling of hawksbill sea turtle growth rates (southern Great Barrier Reef). Marine Ecology Progress Series 146, 18.
Coyne, M.S. and Godley, B.J. (2005) Satellite tracking and analysis tool (STAT): an integrated system for archiving, analysing and mapping animal tracking data. Marine Ecology Progress Series 301, 17.
Diez, C.E. and van Dam, R.P. (2002) Habitat effect on hawksbill turtle growth rates on feeding grounds at Mona and Monito Islands, Puerto Rico. Marine Ecology Progress Series 234, 301309.
Dwyer, R.G., Bearhop, S., Campbell, H.A. and Bryant, D.M. (2013) Shedding light on light: benefits of anthropogenic illumination to a nocturnally foraging shorebird. Journal of Animal Ecology 82, 478485.
Godley, B.J., Lima, E., Akesson, S., Broderick, A.C., Glen, F., Godfrey, M.H., Luschi, P. and Hays, G.C. (2003) Movement patterns of green turtles in Brazilian coastal waters described by satellite tracking and flipper tagging. Marine Ecology Progress Series 253, 279288.
Hart, K., Sartain, A., Fujisaki, I., Pratt, H., Morley, D. and Feeley, M. (2012) Home range, habitat use, and migrations of hawksbill turtles tracked from Dry Tortugas National Park, Florida, USA. Marine Ecology Progress Series 457, 193207.
Hart, K.M., Sartain, A.R., Hillis-Starr, Z.-M., Phillips, B., Mayor, P.A., Roberson, K., Pemberton, R.A., Allen, J.B., Lundgren, I. and Musick, S. (2013) Ecology of juvenile hawksbills (Eretmochelys imbricata) at Buck Island Reef National Monument, US Virgin Islands. Marine Biology 160, 25672580.
Hawkes, L.A., McGowan, A., Broderick, A.C., Gore, S., Wheatley, D., White, J., Witt, M.J. and Godley, B.J. (2014) High rates of growth recorded for hawksbill sea turtles in Anegada, British Virgin Islands. Ecology and Evolution 4, 12551266.
Limpus, C.J. (1992) The hawksbill turtle, Eretmochelys imbricata, in Queensland: population structure within a southern Great Barrier Reef feeding ground. Wildlife Research 19, 489505.
Mansfield, K.L., Wyneken, J., Porter, W.P. and Luo, J. (2014) First satellite tracks of neonate sea turtles redefine the “lost years” oceanic niche. Proceedings of the Royal Society, B 281, 20133039. doi:10.1098/rspb.2013.3039.
Marcovaldi, M., Lopez, G., Soares, L. and López-Mendilaharsu, M. (2012) Satellite tracking of hawksbill turtles Eretmochelys imbricata nesting in northern Bahia, Brazil: turtle movements and foraging destinations. Endangered Species Research 17, 123132.
Marcovaldi, M.A., Vieitas, C.F. and Godfrey, M.H. (1999) Nesting and conservation management of hawksbill turtles (Eretmochelys imbricata) in Northern Bahia, Brazil. Chelonian Conservation and Biology 3, 301307.
Meylan, A.B. (1988) Spongivory in hawksbill turtles: a diet of glass. Science 239, 393395.
Meylan, P.A., Meylan, A.B. and Gray, J.A. (2011) The ecology and migrations of sea turtles. 8. Tests of the developmental habitat hypothesis. Bulletin of the American Museum of Natural History 357, 170.
Moncada, F., Carrillo, E., Saenz, A. and Nodarse, G. (1999) Reproduction and nesting of the hawksbill turtle, Eretmochelys imbricata, in the Cuban archipelago. Chelonian Conservation and Biology 3, 257263.
Monzón-Argüello, C., Loureiro, N.S., Delgado, C., Marco, A., Lopes, J.M., Gomes, M.G. and Abreu-Grobois, F.A. (2011) Príncipe island hawksbills: genetic isolation of an eastern Atlantic stock. Journal of Experimental Marine Biology and Ecology 407, 345354.
Monzón-Argüello, C., Rico, C., Marco, A., López, P. and López-Jurado, L.F. (2010) Genetic characterization of eastern Atlantic hawksbill turtles at a foraging group indicates major undiscovered nesting populations in the region. Journal of Experimental Marine Biology and Ecology 387, 914.
Mortimer, J.A. and Donnelly, M. (2008) Eretmochelys imbricata. In IUCN 2013. The IUCN Red List of Threatened Species. Version 2013.2. Available at: http://www.iucnredlist.org (accessed 8 August 2014).
Musick, J.A. and Limpus, C.J. (1997) Habitat utilisation and migration in juvenile sea turtles. In Lutz, P.L. and Musick, J.A. (eds) The biology of sea turtles. Volume 1. Boca Raton, FL: CRC Press, pp. 137164.
Proietti, M.C., Reisser, J., Marins, L.F., Rodriguez-Zarate, C., Marcovaldi, M.A., Monteiro, D.S., Pattiaratchi, C. and Secchi, E.R. (2014) Genetic structure and natal origins of immature hawksbill turtles (Eretmochelys imbricata) in Brazilian waters. PLoS ONE 9, e88746. doi:10.1371/journal.pone.0088746.
Proietti, M.C., Reisser, J. and Secchi, E.R. (2012) Foraging by immature hawksbill sea turtles at Brazilian islands. Marine Turtle Newsletter 135, 46.
Putman, N.F., Abreu-Grobois, F.A., Broderick, A.C., Ciofi, C., Formia, A., Godley, B.J., Stroud, S., Pelembe, T., Verley, P. and Williams, N. (2014) Numerical dispersal simulations and genetics help explain the origin of hawksbill sea turtles in Ascension Island. Journal of Experimental Marine Biology and Ecology 450, 98108.
Putman, N.F. and Naro-Maciel, E. (2013) Finding the “lost years” in green turtles: insights from ocean circulation models and genetic analysis. Proceedings of the Royal Society, B 280, 20131468.
Renaud, M.L. and Carpenter, J.A. (1994) Movements and submergence patterns of loggerhead turtles (Caretta caretta) in the Gulf of Mexico determined through satellite telemetry. Bulletin of Marine Science 55, 115.
Seminoff, J.A., Resendiz, A. and Nichols, W.J. (2002) Home range of green turtles Chelonia mydas at a coastal foraging area in the Gulf of California, Mexico. Marine Ecology Progress Series 242, 253265.
Scales, K.L., Lewis, J.A., Lewis, J.P., Castellanos, D., Godley, B.J. and Graham, R.T. (2011) Insights into habitat utilisation of the hawksbill turtle, Eretmochelys imbricata (Linnaeus, 1766), using acoustic telemetry. Journal of Experimental Marine Biology and Ecology 407, 122129.
Silvertown, J. (2009) A new dawn for citizen science. Trends in Ecology and Evolution 24, 467471.
Van Dam, R.P. and Diez, C.E. (1998) Home range of immature hawksbill turtles (Eretmochelys imbricata) at two Caribbean islands. Journal of Experimental Marine Biology and Ecology 220, 1524.
Vilaça, S.T., Lara-Ruiz, P., Marcovaldi, M.A., Soares, L.S. and Santos, F.R. (2013) Population origin and historical demography in hawksbill (Eretmochelys imbricata) feeding and nesting aggregates from Brazil. Journal of Experimental Marine Biology and Ecology 446, 334344.
Weber, N., Weber, S.B., Godley, B.J., Ellick, J., Witt, M. and Broderick, A.C. (2013) Telemetry as a tool for improving estimates of marine turtle abundance. Biological Conservation 167, 9096.
Witherington, B., Hirama, S. and Hardy, R. (2012) Young sea turtles of the pelagic Sargassum-dominated drift community: habitat use, population density, and threats. Marine Ecology Progress Series 463, 122.
Witt, M.J., Hardy, T., Johnson, L., McClellan, C.M., Pikesley, S.K., Ranger, S., Richardson, P.B., Solandt, J.L., Speedie, C., Williams, R. and Godley, B.J. (2012) Basking sharks in the northeast Atlantic: spatio-temporal trends from sightings in UK waters. Marine Ecology Progress Series 459, 121134.
Witzell, W.N. (1983) Synopsis of biological data on the hawksbill turtle Eretmochelys imbricata (Linnaeus, 1766). FAO Fisheries Synopsis 137. Rome: FAO.
Wood, L.D., Hardy, R., Meylan, P.A. and Meylan, A.B. (2013) Characterization of a hawksbill turtle (Eretmochelys imbricata) foraging aggregation in a high-latitude reef community in southeastern Florida, USA. Herpetological Conservation and Biology 8, 258275.
Worton, B.J. (1989) Kernel methods for estimating the utilization distribution in home-range studies. Ecology 70, 164168.
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