Growth rings (GR) in sagitally sectioned vertebral centra of 69 female tiger sharks (102–300 cm precaudal length; 6–412 kg) and 32 males (123–301 cm; 16–396 kg) were counted. In vertebrae from three sharks injected with oxytetracyline (OTC) and recaptured after 18, 389 and 791 days of liberty, respectively, OTC was visible and there was evidence of annual GR deposition. Centrum analyses of the entire vertebral sample failed to confirm this GR periodicity. Assuming annual GR deposition, the youngest female and male aged were 1 year (102 cm) and 2 years (123 cm), and the oldest were 11 years (293 cm) and 8 years (301 cm) respectively. von Bertalanffy parameters for the combined sexes based on back-calculated values were L• 301 cm, k 0.202 year−1 and t0 −1.11 years. Ages calculated for length at 50% maturity were 11 years (274 cm) and 8 years (250 cm) for females and males, respectively. Calculated growth in length decreased from 44 cm (0–1 year) to 4 cm (12–13 years). Gompertz parameters were w0 14 kg, G 3.73 and g 0.172 year−1. Calculated growth in mass increased from 12 kg (0–1 year) to 38 kg (7–8 years), then decreased to 29 kg (12–13 years). Back-calculated length and mass values were similar to observed values and Lee’s phenomenon was not evident in either case.

Growth rings (GR) were counted in vertebrae of 69 female (56–221 cm precaudal length; 3–238 kg) and 54 male (57–216 cm; 3–180 kg) C. leucas. Annual GR deposition could not be confirmed by centrum edge analyses but was assumed on the basis of ‘mark–recapture’ analysis of 10 sharks held captive for between 2.2 and 20 years in an aquarium. GR counts indicated that the largest female and male were 32 years (221 cm) and 29 years (216 cm), respectively and the smallest mature female and male were 14 years (197 cm) and 25 years (196 cm). Length at 50% maturity was 193 cm (21 years) and 190 cm (20 years) for females and males, respectively. Maximum age is >50 years, and the two specimens (216, 217 cm) that have been held in the aquarium for 20 years are both estimated to be >29 years. Von Bertalanffy parameters for the combined sexes were L∞ = 230 cm, k = 0.071 year–1, t0 = –5.12 years, and Gompertz parameters were w0 = 24 kg, G = 2.86, g = 0.046 year–1.

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