The spatial ecology of juvenile loggerhead turtles (Caretta caretta) in the Indian Ocean sheds light on the “lost years” mystery


While our understanding of the early oceanic developmental stage of sea turtles has improved markedly over recent decades, the spatial context for this life history stage remains unknown for Indian Ocean loggerhead turtle populations. To address this gap in our knowledge, 18 juvenile loggerheads were satellite tracked from Reunion Island (21.2°S, 55.3°E) between 2007 and 2011. Nine turtles swam north toward Oman (20.5°N, 58.8°E), where one of the world’s largest rookeries of loggerheads is located. Three individuals traveled south toward South Africa and Madagascar, countries that also host loggerhead nesting grounds. Fourteen of the transmitters relayed diving profiles. A dichotomy between diurnal and nocturnal diving behavior was observed with a larger number of shorter dives occurring during the day. Diving behavior also differed according to movement behavior as individuals spent more time in subsurface waters (between 10 and 20 m) during transit phases. The study provides an understanding of the oceanic movement behavior of juvenile loggerheads in the Indian Ocean that suggests the existence of an atypical trans-equatorial developmental cycle for the species at the ocean basin scale in the Indian Ocean. These results address a significant gap in the understanding of loggerhead oceanic movements and may help with the conservation of the species.

This is a preview of subscription content, log in to check access.

Access options

Buy single article

Instant unlimited access to the full article PDF.

US$ 39.95

Price includes VAT for USA

Subscribe to journal

Immediate online access to all issues from 2019. Subscription will auto renew annually.

US$ 199

This is the net price. Taxes to be calculated in checkout.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6


  1. Arendt MD, Segars AL, Byrd JI, Boynton J, Whitaker JD, Parker L, Owens DW, Blanvillain G, Quattro JM, Roberts MA (2012) Seasonal distribution patterns of juvenile loggerhead sea turtles (Caretta caretta) following capture from a shipping channel in the Northwest Atlantic Ocean. Mar Biol 159(1):127–139. doi:10.1007/s00227-011-1829-x

  2. Avens L, Snover M (2013) Age and age estimation in sea turtles. In: The biology of sea turtles, volume III. Marine biology. CRC Press, pp 97–134. doi:10.1201/b13895-6

  3. Baldwin RM, Hughes GR, Prince RIT (2003) Loggerhead turtles in the Indian Ocean. In: Bolten AB, Witherington BE (eds) Loggerhead sea turtles. Smithsonian Books, Washington, pp 218–232

  4. Barraquand F, Benhamou S (2008) Animal movements in heterogeneous landscapes: identifying profitable places and homogeneous movement bouts. Ecology 89(12):3336–3348. doi:10.1890/08-0162.1

  5. Behrenfeld MJ, Falkowski PG (1997) Photosynthetic rates derived from satellite-based chlorophyll concentration, vol 1. American Society of Limnology and Oceanography, Waco

  6. Bjorndal KA, Bolten AB, Martins HR (2000) Somatic growth model of juvenile loggerhead sea turtles Caretta caretta: duration of pelagic stage. Mar Ecol Prog Ser 202:265–272. doi:10.3354/meps202265

  7. Bjorndal K, Schroeder B, Foley A, Witherington B, Bresette M, Clark D, Herren R, Arendt M, Schmid J, Meylan A, Meylan P, Provancha J, Hart K, Lamont M, Carthy R, Bolten A (2013) Temporal, spatial, and body size effects on growth rates of loggerhead sea turtles (Caretta caretta) in the Northwest Atlantic. Mar Biol 1–11. doi:10.1007/s00227-013-2264-y

  8. Bolten AB (2003) Variation in sea turtle life history patterns: Neritic vs. Oceanic developmental stages. In: Lutz PL, Musick A, Wyneken J (eds) The biology of sea turtles, vol 2. Marine science series. CRC Press, Boca Raton, pp 243–258

  9. Bowen BW, Karl SA (2007) Population genetics and phylogeography of sea turtles. Mol Ecol 16(23):4886–4907. doi:10.1111/j.1365-294X.2007.03542.x

  10. Bowen BW, Abreu-Grobois FA, Balazs GH, Kamezaki N, Limpus CJ, Ferl RJ (1995) Trans-Pacific migrations of the loggerhead turtle (Caretta caretta) demonstrated with mitochondrial DNA markers. Proc Natl Acad Sci 92(9):3731–3734. doi:10.1073/pnas.92.9.3731

  11. Boyle MC, FitzSimmons NN, Limpus CJ, Kelez S, Velez-Zuazo X, Waycott M (2009) Evidence for transoceanic migrations by loggerhead sea turtles in the southern Pacific Ocean. Proc R Soc B Biol Sci 276(1664):1993–1999. doi:10.1098/rspb.2008.1931

  12. Breed GA, Jonsen ID, Myers RA, Bowen WD, Leonard ML (2009) Sex-specific, seasonal foraging tactics of adult grey seals (Halichoerus grypus) revealed by state-space analysis. Ecology 90(11):3209–3221. doi:10.1890/07-1483.1

  13. Carr AF (1952) Handbook of turtles: the turtles of the United States, Canada, and Baja California. Comstock, Ithaca

  14. Carr AF (1986) The sea turtle: so excellent a fishe. University of Texas Press, Austin

  15. Ciccione S, Bourjea J (2010) Discovering behaviour of open sea stages of sea turtles: working flipper on hand with fishermen in Réunion. Indian Ocean Turtle Newsl 11:p50–p52

  16. Coles W, Musick JA, Price AH (2000) Satellite sea surface temperature analysis and correlation with sea turtle distribution off North Carolina. Copeia 2:551–554. doi:10.1643/0045-8511(2000)000[0551:ssstaa];2

  17. Doyle TK, Houghton JD, O’Súilleabháin PF, Hobson VJ, Marnell F, Davenport J, Hays GC (2008) Leatherback turtles satellite-tagged in European waters. Endanger Species Res 4(1–2):23–31. doi:10.3354/esr00076

  18. Evano H, Bourjea J (2012) Atlas de la pêche palangrière réunionnaise de l’océan Indien, p 245. doi:

  19. Fonteneau A, Lucas V, Tewkai E, Delgado A, Demarcq H (2008) Mesoscale exploitation of a major tuna concentration in the Indian Ocean. Aquat Living Resour 21(2):109–121. doi:10.1051/alr:2008028

  20. Galli S, Gaspar P, Fossette S, Calmettes B, Hays GC, Lutjeharms JRE, Luschi P (2012) Orientation of migrating leatherback turtles in relation to ocean currents. Anim Behav 84(6):1491–1500. doi:10.1016/j.anbehav.2012.09.022

  21. Gaspar P, Benson SR, Dutton PH, Reveillere A, Jacob G, Meetoo C, Dehecq A, Fossette S (2012) Oceanic dispersal of juvenile leatherback turtles: going beyond passive drift modeling. Mar Ecol Prog Ser 457:265–284. doi:10.3354/meps09689

  22. Gilman E, Zollett E, Beverly S, Nakano H, Davis K, Shiode D, Dalzell P, Kinan I (2006) Reducing sea turtle by-catch in pelagic longline fisheries. Fish Fish 7(1):2–23. doi:10.1111/j.1467-2979.2006.00196.x

  23. Girard C, Sudre J, Benhamou S, Roos D, Luschi P (2006) Homing in green turtles Chelonia mydas: oceanic currents act as a constraint rather than as an information source. Mar Ecol Prog Ser 322:281–289. doi:10.3354/meps322281

  24. Godley BJ, Broderick AC, Glen F, Hays GC (2003) Post-nesting movements and submergence patterns of loggerhead marine turtles in the Mediterranean assessed by satellite tracking. J Exp Mar Biol Ecol 287(1):119–134. doi:10.1016/s0022-0981(02)00547-6

  25. Halpin PN, Read AJ, Fujioka E, Best BD, Donnelly B, Hazen LJ, Kot C, Urian K, LaBrecque E, Dimatteo A, Cleary J, Good C, Crowder LB, Hyrenbach KD (2009) OBIS-SEAMAP: the world data center for marine mammal, sea bird, and sea turtle distributions. Oceanography 22(2):104–115

  26. Hawkes LA, Broderick AC, Coyne MS, Godfrey MH, Lopez-Jurado L-F, Lopez-Suarez P, Merino SE, Varo-Cruz N, Godley BJ (2006) Phenotypically linked dichotomy in sea turtle foraging requires multiple conservation approaches. Curr Biol (CB) 16(10):990–995

  27. Hays GC, Scott R (2013) Global patterns for upper ceilings on migration distance in sea turtles and comparisons with fish, birds and mammals. Funct Ecol 27(3):748–756. doi:10.1111/1365-2435.12073

  28. Hays GC, Akesson S, Broderick AC, Glen F, Godley BJ, Luschi P, Martin C, Metcalfe JD, Papi F (2001) The diving behaviour of green turtles undertaking oceanic migration to and from Ascension Island: dive durations, dive profiles and depth distribution. J Exp Biol 204(23):4093–4098

  29. Hays GC, Fossette S, Katselidis KA, Mariani P, Schofield G (2010) Ontogenetic development of migration: Lagrangian drift trajectories suggest a new paradigm for sea turtles. J R Soc Interface 7(50):1319–1327. doi:10.1098/rsif.2010.0009

  30. Heileman S, Eghtesadi-Araghi P, Mistafa N (2009) Arabian Sea: LME. The Unep large marine ecosystems report, a perspective on changing conditions in MLEs of the world’s regional seas, vol UNEP Regional Seas Report and Studies, Nairobi, Kenya

  31. Hoenner X, Whiting SD, Hindell MA, McMahon CR (2012) Enhancing the use of argos satellite data for home range and long distance migration studies of marine animals. Plos One 7(7). doi:10.1371/journal.pone.0040713

  32. Holyoak M, Casagrandi R, Nathan R, Revilla E, Spiegel O (2008) Trends and missing parts in the study of movement ecology. Proc Natl Acad Sci 105(49):19060–19065

  33. Houghton JDR, Broderick AC, Godley BJ, Metcalfe JD, Hays GC (2002) Diving behaviour during the interesting interval for loggerhead turtles Caretta caretta nesting in Cyprus. Mar Ecol Prog Ser 227:63–70

  34. Houghton JDR, Doyle TK, Davenport J, Wilson RP, Hays GC (2008) The role of infrequent and extraordinary deep dives in leatherback turtles (Dermochelys coriacea). J Exp Biol 211(16):2566–2575. doi:10.1242/jeb.020065

  35. Howell E, Dutton P, Polovina J, Bailey H, Parker D, Balazs G (2010) Oceanographic influences on the dive behavior of juvenile loggerhead turtles (Caretta caretta) in the North Pacific Ocean. Mar Biol 157(5):1011–1026. doi:10.1007/s00227-009-1381-0

  36. Hughes GR (1973) The sea turtles of south east Africa. Doctoral thesis, University of Natal, Durban

  37. Hughes GR (1974) The sea turtles of South-East Africa II. The biology of the Tongaland loggerhead turtle Caretta caretta L. with comments on the leatherback turtle Dermochelys coriacea L. and the green turtle Chelonia mydas L. in the study region. Investigational Report

  38. Hughes GR (2010) Loggerheads and leatherbacks in the Western Indian Ocean. Indian Ocean Turtle Newsl 11:24–31

  39. Hughes GR (2012) Between the tides. Jacana Publishers, Cape Town

  40. IUCN (2012) The IUCN red list of threatened species. Accessed 01 June 2013

  41. Kendall BE, Fox GA (1998) Spatial structure, environmental heterogeneity, and population dynamics: analysis of the coupled logistic map. Theor Popul Biol 54(1):11–37. doi:10.1006/tpbi.1998.1365

  42. Kobayashi DR, Polovina JJ, Parker DM, Kamezaki N, Cheng IJ, Uchida I, Dutton PH, Balazs GH (2008) Pelagic habitat characterization of loggerhead sea turtles, Caretta caretta, in the North Pacific Ocean (1997–2006): insights from satellite tag tracking and remotely sensed data. J Exp Mar Biol Ecol 356(1–2):96–114

  43. Lavielle M (2005) Using penalized contrasts for the change-point problem. Signal Process 85(8):1501–1510. doi:10.1016/j.sigpro.2005.01.012

  44. Lévy M, Shankar D, André JM, Shenoi SSC, Durand F, de Boyer Montégut C (2007) Basin-wide seasonal evolution of the Indian Ocean’s phytoplankton blooms. J Geophys Res Oceans 112(C12):C12014. doi:10.1029/2007jc004090

  45. Lewison RL, Freeman SA, Crowder LB (2004) Quantifying the effects of fisheries on threatened species: the impact of pelagic longlines on loggerhead and leatherback sea turtles. Ecol Lett 7(3):221–231. doi:10.1111/j.1461-0248.2004.00573.x

  46. Longhurst AR (1998) Ecological geography of the sea. Academic Press, San Diego

  47. Luschi P, Lutjeharm JRE, Lambardi R, Mencacci R, Hughes GR, Hays GC (2006) A review of migratory behaviour of sea turtles off Southeastern Africa. S Afr J Sci 102(1–2):51–58

  48. Mansfield K, Saba V, Keinath J, Musick J (2009) Satellite tracking reveals a dichotomy in migration strategies among juvenile loggerhead turtles in the Northwest Atlantic. Mar Biol 156(12):2555–2570. doi:10.1007/s00227-009-1279-x

  49. Martel B (2003) Les facteurs intervenant dans la selection des sites de ponte de la caouanne (Caretta caretta) sur les côtes malgaches, vol 4. Société de biogéographie, Paris

  50. McClellan CM, Read AJ (2007) Complexity and variation in loggerhead sea turtle life history. Biol Lett 3(6):592–594. doi:10.1098/rsbl.2007.0355

  51. McClellan CM, Braun-McNeill J, Avens L, Wallace BP, Read AJ (2010) Stable isotopes confirm a foraging dichotomy in juvenile loggerhead sea turtles. J Exp Mar Biol Ecol 387(1–2):44–51. doi:10.1016/j.jembe.2010.02.020

  52. Miossec D, Bourjea J (2003) Longline fishery evolution in La Réunion. Focus on the exploitation level of swordfish (Xiphias gladius). Paper presented at the 3rd session of the IOTC working party on billfish, Perth, Australia, 10–12 Nov

  53. Monzon-Arguello C, Dell’Amico F, Moriniere P, Marco A, Lopez-Jurado LF, Hays GC, Scott R, Marsh R, Lee PLM (2012) Lost at sea: genetic, oceanographic and meteorological evidence for storm-forced dispersal. J R Soc Interface 9(73):1725–1732. doi:10.1098/rsif.2011.0788

  54. Monzón-Argüello C, López-Jurado LF, Rico C, Marco A, López P, Hays GC, Lee PLM (2010) Evidence from genetic and Lagrangian drifter data for transatlantic transport of small juvenile green turtles. J Biogeogr 37(9):1752–1766. doi:10.1111/j.1365-2699.2010.02326.x

  55. Musick JA, Limpus CJ (1997) Habitat utilization and migration in juvenile sea turtles. In: Lutz PL, Musick JA (eds) The biology of sea turtles. vol Marine science series. CRC Press, Boca Raton, pp 137–163

  56. Nathan R, Getz WM, Revilla E, Holyoak M, Kadmon R, Saltz D, Smouse PE (2008) A movement ecology paradigm for unifying organismal movement research. Proc Natl Acad Sci 105(49):19052–19059. doi:10.1073/pnas.0800375105

  57. Nel R, Punt AE, Hughes GR (2013) Are coastal protected areas always effective in achieving population recovery for nesting sea turtles? PLoS One 8(5):e63525. doi:10.1371/journal.pone.0063525

  58. Peckham SH, Maldonado Diaz D, Walli A, Ruiz G, Crowder LB, Nichols WJ (2007) Small-scale fisheries bycatch jeopardizes endangered Pacific loggerhead turtles. PLoS One 2(10):e1041

  59. Peckham SH, Maldonado-Diaz D, Tremblay Y, Ochoa R, Polovina J, Balazs G, Dutton PH, Nichols WJ (2011) Demographic implications of alternative foraging strategies in juvenile loggerhead turtles Caretta caretta of the North Pacific Ocean. Mar Ecol Prog Ser 425:269–280. doi:10.3354/meps08995

  60. Petersen SL, Honig MB, Ryan PG, Nel R, Underhill LG (2009) Turtle bycatch in the pelagic longline fishery off southern Africa. Afr J Mar Sci 31(1):87–96. doi:10.2989/ajms.2009.

  61. Polovina JJ, Howell E, Parker DM, Balazs GH (2003) Dive-depth distribution of loggerhead (Carretta carretta) and olive ridley (Lepidochelys olivacea) sea turtles in the central North Pacific: might deep longline sets catch fewer turtles? Fish Bull 101(1):189–193

  62. Polovina JJ, Balazs GH, Howell EA, Parker DM, Seki MP, Dutton PH (2004) Forage and migration habitat of loggerhead (Caretta caretta) and olive ridley (Lepidochelys olivacea) sea turtles in the central North Pacific Ocean. Fish Oceanogr 13(1):36–51

  63. Putman N, Scott R, Verley P, Marsh R, Hays G (2012) Natal site and offshore swimming influence fitness and long-distance ocean transport in young sea turtles. Mar Biol 159(10):2117–2126. doi:10.1007/s00227-012-1995-5

  64. Rakotonirina BP (2011) Etude éthno-biologique sur tortues marines à Madagascar (Sud-Ouest de l’océan Indien). PhD Thesis, Université de Toliara, Toliara

  65. Read AJ (2007) Do circle hooks reduce the mortality of sea turtles in pelagic longlines? A review of recent experiments. Biol Conserv 135(2):155–169. doi:10.1016/j.biocon.2006.10.030

  66. Rees A, Al Saady S, Broderick A, Coyne M, Papathanasopoulou N, Godley B (2010) Behavioural polymorphism in one of the world’s largest populations of loggerhead sea turtles Caretta caretta. Mar Ecol Prog Ser 418:201–212. doi:10.3354/meps08767

  67. Renaud ML, Carpenter JA (1994) Movements and submergence patterns of loggerhead turtles (Caretta caretta) in the Gulf-of-Mexico determined through satellite telemetry. Bull Mar Sci 55(1):1–15

  68. Revelles M, Isem-Fontanet J, Cardona L, Felix MS, Carreras C, Aguilar A (2007) Mesoscale eddies, surface circulation and the scale of habitat selection by immature loggerhead sea turtles. J Exp Mar Biol Ecol 347(1–2):41–57. doi:10.1016/j.jembe.2007.03.013

  69. Rice MR, Balazs GH (2008) Diving behavior of the Hawaiian green turtle (Chelonia mydas) during oceanic migrations. J Exp Mar Biol Ecol 356(1–2):121–127

  70. Ross JP (1998) Estimations of the nesting population size of loggerhead sea turtles, Caretta caretta, Masirah Island, Sultanate of Oman. NMFS-SEFSC

  71. Ross JP, Barwani MA (1995) Review of sea turtles in the Arabian area. In: Bjorndal KA (ed) Biology and conservation of sea turtles, revised edition. Smithsonian Institute Press, Washington, pp 373–383

  72. Savtchenko A, Ouzounov D, Ahmad S, Acker J, Leptoukh G, Koziana J, Nickless D (2004) Terra and Aqua MODIS products available from NASA GES DAAC. Adv Space Res 34(4):710–714. doi:10.1016/j.asr.2004.03.012

  73. Schott FA, McCreary JP (2001) The monsoon circulation of the Indian Ocean. Prog Oceanogr 51(1):1–123. doi:10.1016/s0079-6611(01)00083-0

  74. Schott FA, Xie S-P, McCreary JP, Jr (2009) Indian Ocean circulation and climate variability. Rev Geophys 47(1):RG1002. doi:10.1029/2007rg000245

  75. Scott R, Marsh R, Hays GC (2012) Life in the really slow lane: loggerhead sea turtles mature late relative to other reptiles. Funct Ecol 26(1):227–235. doi:10.1111/j.1365-2435.2011.01915.x

  76. Shillinger GL, Di Lorenzo E, Luo H, Bograd SJ, Hazen EL, Bailey H, Spotila JR (2012) On the dispersal of leatherback turtle hatchlings from Mesoamerican nesting beaches. Proc R Soc B Biol Sci 279(1737):2391–2395. doi:10.1098/rspb.2011.2348

  77. Sudre J, Maes C, Garçon V (2013) On the global estimates of geostrophic and Ekman surface currents. Limnol Oceanogr Fluids Environ 3:1–20. doi:10.1215/21573689-2071927

  78. Tew Kai E, Marsac F (2009) Patterns of variability of sea surface chlorophyll in the Mozambique Channel: a quantitative approach. J Mar Syst 77(1–2):77–88. doi:10.1016/j.jmarsys.2008.11.007

  79. Tew Kai E, Marsac F (2010) Influence of mesoscale eddies on spatial structuring of top predators’ communities in the Mozambique Channel. Prog Oceanogr 86(1–2):214–223. doi:10.1016/j.pocean.2010.04.010

  80. Tew Kai E, Rossi V, Sudre J, Weimerskirch H, Lopez C, Hernandez-Garcia E, Marsac F, Garçon V (2009) Top marine predators track Lagrangian coherent structures. Proc Natl Acad Sci 106(20):8245–8250. doi:10.1073/pnas.0811034106

  81. Tilman DE, Kareiva PME (1997) Spatial ecology: the role of space in population dynamics and interspecific interactions. Princeton University Press, Princeton

  82. Wyneken J, Salmon M (1992) Frenzy and postfrenzy swimming activity in loggerhead, green, and leatherback hatchling sea-turtles. Copeia 2:478–484

Download references


The authors are grateful to the organizations that contributed to funding the study: DEAL La Réunion, Région Réunion, Fondation Crédit Agricole, CLS-Argos, and University of La Réunion. Mayeul Dalleau personally thanks Région Réunion for funding his PhD studentship. The authors also wish to thank all the people and organizations that made this study possible, especially boat captains and crew members of Réunion Island longline vessels boats that collaborated with the program; Francis Schneider and his veterinary team for surgical operations and medical care, the Kélonia team for medical care and awareness programs, the school children and teachers for sponsorships, and Dr. Georges Hughes for correcting the English of the current article. The study was conducted under authorization no. 09-1405/SG/DRCTCV issued by the Reunion Island prefecture on 2009-05-11. At last, we wish to thank the reviewers that contributed improving this paper and the editor for his useful comments.

Author information

Correspondence to Mayeul Dalleau.

Additional information

Communicated by J. D. R. Houghton.

Electronic supplementary material

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Dalleau, M., Benhamou, S., Sudre, J. et al. The spatial ecology of juvenile loggerhead turtles (Caretta caretta) in the Indian Ocean sheds light on the “lost years” mystery. Mar Biol 161, 1835–1849 (2014).

Download citation


  • Indian Ocean
  • Diving Behavior
  • Dive Duration
  • Loggerhead Turtle
  • Southern Group