Marine Biology

, Volume 152, Issue 6, pp 1309–1317 | Cite as

Comparative skeletochronological analysis of Kemp’s ridley (Lepidochelys kempii) and loggerhead (Caretta caretta) humeri and scleral ossicles

  • Larisa AvensEmail author
  • Lisa R. Goshe
Research Article


Skeletochronological analysis of Kemp’s ridley (Lepidochelys kempii) and loggerhead (Caretta caretta) sea turtle humeri and scleral ossicles was conducted to (1) describe the characteristics of scleral ossicles in these species, (2) determine whether the scleral ossicles contain annually deposited skeletal growth marks and (3) evaluate the potential for skeletochronological analysis of ossicles to obtain age data for size classes and species of sea turtles whose humeri exhibit prohibitive amounts of growth mark resorption. Humeri, entire eyes, and/or individual scleral ossicles were collected from stranded, dead sea turtles that were found along the coasts of Florida, North Carolina, Virginia, and Texas, USA. Samples were taken from a total of 77 neritic, juvenile Kemp’s ridleys ranging from 21.1 to 56.8 cm straightline carapace length (SCL), as well as two Kemp’s ridley hatchlings. For loggerheads, samples were obtained from 65 neritic juvenile and adult turtles ranging from 44.7 to 103.6 cm SCL and ten hatchlings. Examination of the ossicles revealed the presence of marks similar in appearance to those found in humeri. The number of marks in the ossicles and humeri of individual juvenile Kemp’s ridleys for which both structures were collected (n = 55) was equivalent, strongly indicating that the marks are annual. However, in large juvenile and adult loggerhead turtles (n = 65), some significant resorption of early growth marks was observed, suggesting that although ossicles might be useful for skeletochronological analysis of small juveniles, they may not provide a reasonable alternative to humeri for obtaining age estimates for older loggerhead sea turtles.


Growth Mark Curve Carapace Length Caretta Caretta Individual Turtle Core Mark 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This research could not have been accomplished without the samples collected through the efforts of the National Sea Turtle Stranding and Salvage Network. We are grateful to the North Carolina Wildlife Resources Commission, especially to M. Godfrey, W. Cluse, and R. Boettcher, to the National Park Service at Cape Lookout National Seashore, particularly J. Cordes, as well as to J. Braun-McNeill, A. Goodman, the Florida Department of Environmental Protection, B. Higgins, and S. Kethan. Special thanks go to M. Snover, A. Gorgone, and B. Brown for initial processing of humeri, to A. Gorgone for assistance with photography, and to A. Hohn and M. Snover for discussions and helpful suggestions pertaining to this research. This manuscript was improved by comments from M. Godfrey, L. Hansen, A. Hohn, P. Marraro, W. Richards, M. Snover, and C. Taylor. Research was conducted under NMFS Scientific Research Permit #1260 and USFWS Permit #TE-676379-2 issued to the NMFS SERO.


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.Southeast Fisheries Science Center, Center for Coastal Fisheries and Habitat ResearchNOAA FisheriesBeaufortUSA

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