Abstract
Sea turtles bury their eggs in nests at depths ranging from 25 to 100 cm. After hatching, turtles crawl up to the surface and emerge over several days. Some hatchlings fail to emerge and die in the sand column. In this study, we investigated the effect of the depth of the drying front (the region separating saturated and partially dry sand), number of hatchlings emerging, depth of nest and temperature on the emergence of hatchling leatherback turtles (Dermochelys coriacea) over the course of three nesting seasons (2008–2009, 2011–2012 and 2012–2013) at Playa Grande, Costa Rica. The depth of the drying front affected the number of hatchlings that failed to emerge in all years and high temperature reduced emergence rate in 2008–2009 and 2012–2013, but not in 2011–2012. Most of the variability in emergence rate was explained by the number of hatchlings emerging and the depth of the drying front. The number of dead hatchlings was mainly explained by the depth of the drying front and temperature. Depth zones within the sand column that included the drying front and the egg chamber registered the greatest number of dead hatchlings. The depth of the drying front, temperature and number of hatchlings remaining in the sand column increased and the emergence rate decreased as the season progressed. Leatherback turtles are critically endangered in the eastern Pacific Ocean. Conservation strategies towards improving the conditions in the nest environment (i.e. nest irrigation and shading to decrease the depth of the drying front and temperature) could boost hatchling production and contribute to revert declining population trends.
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References
Ackerman RA (1991) Physical factors affecting the water exchange of buried reptile eggs. In: Deeming DC, Ferguson MWJ (eds) Egg incubation: its effects on embryonic development in birds and reptiles. Cambridge University Press, Cambridge, pp 201–204
Ackerman RA, Lott DB (2004) Thermal, hydric and respiratory climate of nests. In: Deeming DC (ed) Reptilian incubation: environment, evolution and behaviour. Nottingham University Press, UK, pp 20–36
Bennett JM, Taplin LE, Grigg GC (1986) Sea water drinking as a homeostatic response to dehydration in hatchling loggerhead turtles Caretta caretta. Comp Biochem Physiol Part A Physiol 83:507–513
Bézy V, Valverde RA, Plante CJ (2015) Olive ridley sea turtle hatching success as a function of the microbial abundance in nest sand at Ostional, Costa Rica. PLoS ONE 10(2):e0118579
Booth DT, Astill K (2001) Temperature variation within and between nests of the green sea turtle, Chelonia mydas (Chelonia: Cheloniidae), on Heron Island, Great Barrier Reef. Aust J Zool 49:71–84
Booth DT, Burgess E, McCosker J, Lanyon JM (2004) The influence of incubation temperature on post-hatching fitness characteristics of turtles. Int Congr Ser 1275:226–233
Bustard HR (1967) Mechanisms of nocturnal emergence from the nest in green sea turtle hatchlings. Nature 214:317
Carr A, Hirth H (1960) Social facilitation in green turtle siblings. Anim Behav 9:68–70
Carr A, Ogren L (1959) The ecology and migration of sea turtles, 3 Dermochelys in Costa Rica. Am Mus Novit 1958:1–29
Clusella-Trullas S, Spotila JR, Paladino FV (2006) Energetics during hatchling dispersal of the Olive ridley Lepidochelys olivacea using doubly labelled water. Physiol Biochem Zool 79:389–399
Corp IBM (2011) IBM SPSS statistics for windows, Version 20.0. Armonk, IBM Corp
Drake DL, Spotila JR (2002) Thermal tolerances and the timing of sea turtle hatchling emergence. J Therm Biol 27:71–81
Finkler MS (2006) Does variation in soil water content induce variation in the size of hatchling snapping turtles (Chelydra serpentina)? Copeia 2006:769–777
Houghton JDR, Myers AE, Lloyd C, King RS, Isaacs C, Hays GC (2007) Protracted rainfall decreases temperature within leatherback turtle (Dermochelys coriacea) clutches in Grenada, West Indies: ecological implications for a species displaying temperature dependant sex determination. J Exp Mar Biol Ecol 345:71–77
Huang WS, Pike DA (2013) Testing cost-benefit models of parental care evolution using lizard populations with facultative expression of maternal care. PLoS ONE 8:e54065
IUCN (2013) IUCN Red List of threatened species. Version 2013.2. www.iucnredlist.org. Downloaded on 07 Feb 2014
Köhler G (2005) Incubation of reptile eggs. Krieger Publishing Company, Malabar
Kraemer JE, Bennett SH (1981) Utilization of posthatching yolk in loggerhead sea turtles, Caretta caretta. Copeia 1981:406–411
Lohmann KJ, Witherington BE, Lohmann CMF, Salmon M (1997) Orientation, navigation and natal beach homing in sea turtles. In: Lutz PL, Muslck JA (eds) The biology of sea turtles, vol 1. CRC Press, Boca Raton, pp 108–110
Matsuzawa Y, Sato K, Sakamoto W, Bjorndal KA (2001) Seasonal fluctuations in sand temperature: effects on the incubation period and mortality of loggerhead sea turtle (Caretta caretta) pre-emergent hatchlings at Minabe, Japan. Mar Biol 140:639–646
McGehee MA (1990) Effects of moisture on eggs and hatchlings of loggerhead sea turtles (Caretta caretta). Herpetologica 46:251–258
Miller JD (1997) Reproduction in sea turtles. In: Lutz PL, Muslck JA (eds) The biology of sea turtles, vol 1. CRC Press, Boca Raton, pp 64–69
Mrosovsky N (1968) Nocturnal emergence of hatchling sea turtles: control by thermal inhibition of activity. Nature 220:1338–1339
NOAA (2015) National weather service: Climate prediction center. <http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml>. Downloaded on 02 Feb 2015
Patino-Martinez J, Marco A, Quinones L, Hawkes L (2012) A potential tool to mitigate the impacts of climate change to the Caribbean leatherback sea turtle. Glob Change Biol 118:401–411
Peters A, Verhoeven KJF, Strijbosch H (1994) Hatching and emergence in the Turkish Mediterranean loggerhead turtle, Caretta caretta: natural causes for egg and hatchling failure. Herpetologica 50:369–373
Saba VS, Stock CA, Spotila JR, Paladino FP, Santidrián Tomillo P (2012) Projected response of an endangered marine turtle population to climate change. Nat Clim Change 2:814–820
Sahoo G, Sahoo RK, Mohanty-Hejmadi P (1998) Calcium metabolism in olive ridley turtle eggs during embryonic development. Comp Biochem Phys A 121:91–97
Santidrián Tomillo P, Saba VS, Piedra R, Paladino FV, Spotila JR (2008) Effects of illegal harvest of eggs on the population decline of leatherback turtles in Las Baulas Marine National Park, Costa Rica. Conserv Biol 22:1216–1224
Santidrián Tomillo P, Suss JS, Wallace BP, Magrini KD, Blanco G, Paladino FV, Spotila JR (2009) Influence of emergence success on the annual reproductive output of leatherback turtles. Mar Biol 156:2021–2031
Santidrián Tomillo P, Paladino FV, Suss JS, Spotila JR (2010) Predation of leatherback turtle hatchlings during the crawl to the water. Chelonian Conserv Biol 9:18–25
Santidrián Tomillo P, Saba VS, Blanco GS, Stock CA, Paladino FV, Spotila JR (2012) Climate driven egg and hatchling mortality threatens survival of Eastern Pacific leatherback turtles. PLoS ONE 7(5):e37602
Santidrián Tomillo P, Oro D, Paladino FV, Piedra R, Sieg AE, Spotila JR (2014) High beach temperatures increase female-biased primary sex ratios but reduce output of female hatchlings in the leatherback turtle. Biol Conserv 176:71–79
Santidrián Tomillo P, Saba VS, Lombard CD, Valiulis JM, Robinson NJ, Paladino FV, Spotila JR, Fernandez C, Rivas ML, Tucek J, Nel R, Oro D (2015) Global analysis of the effect of local climate on the hatchling output of leatherback turtles. Sci Rep UK 5:16789
Santidrián Tomillo P, Fonseca L, Paladino FV, Spotila JR, Oro D (2017) Are thermal barriers “higher” in deep sea turtle nests? PLoS ONE 12(5):e0177256
Segura LN, Cajade R (2010) The effects of sand temperatures on pre-emergent green turtle hatchlings. Herpetol Conserv Biol 5:196–206
Shokri N, Lehmann P, Vontobel P, Or D (2008) Drying front and water content dynamics during evaporation from sand delineated by neutron radiography. Water Resour Res. https://doi.org/10.1029/2007WR006385
Spotila JR (2004) Sea turtles: a complete guide to their biology, behavior, and conservation. Johns Hopkins University Press, Baltimore
Spotila JR, Reina RD, Steyermark AC, Plotkin PT, Paladino FV (2000) Pacific leatherback turtles face extinction. Nature 405:529–530
Standora EA, Spotila JR (1985) Temperature dependent sex determinations in sea turtles. Copeia 1985:711–722
Wallace BP, Sotherland PR, Spotila JR, Reina RD, Franks BF, Paladino FV (2004) Biotic and abiotic factors affect the nest environment of embryonic leatherback turtles, Dermochelys coriacea. Physiol Biochem Zool 77:423–432
Wallace BP, Sotherland PR, Santidrián Tomillo P, Reina RD, Spotila JR, Paladino FV (2007) Maternal investment in reproduction and its consequences in leatherback turtles. Oecologia 152:37–47
Acknowledgements
We thank all the field biologists and Earthwatch volunteers responsible for collecting the data used in this investigation at the Goldring-Gund Marine Biology Station, the Director and Park Rangers at Parque Nacional Marino Las Baulas, and the staff of the Leatherback Trust at the station and in San Jose.
Funding
This study was funded by a grant from the EARTHWATCH Institute, the Schrey Chair of Biology at IPFW and the Betz Chair of Environmental Science at Drexel University. PST was funded by a Marie Curie International Incoming Fellowship within the 7th European Community Framework Programme.
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All applicable international, national and/or institutional guidelines for the care and use of animals were followed. The study was approved by the Animal Care committee of Drexel University and research permits were obtained from the Ministry of Environment and Energy of Costa Rica (MINAE).
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Swiggs, J., Paladino, F.V., Spotila, J.R. et al. Depth of the drying front and temperature affect emergence of leatherback turtle hatchlings from the nest. Mar Biol 165, 91 (2018). https://doi.org/10.1007/s00227-018-3350-y
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DOI: https://doi.org/10.1007/s00227-018-3350-y