Age and growth estimates of the bull shark,Carcharhinus leucas,from the northern Gulf of Mexico |
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Authors: | Steven Branstetter Robert Stiles |
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Institution: | (1) Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, 77843, U.S.A.;(2) Department of Biology, Samford University, Birmingham, AL, 35209, U.S.A. |
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Abstract: | Synopsis Length at age and growth rates for 59 bull sharks, Carcharhinus leucas, collected from the northern Gulf of Mexico were estimated from the band patterns formed seasonally in the vertebral centra. The combined age at length data for both sexes were applied to a von Bertalanffy growth model producing parameter estimates of L = 285 cm TL, K = .076, t0 = –3.0 yr. Lengths at age for males and females were similar except that males did not attain as great a length as females. Growth was apparently slow and varied among individuals, but in general, was estimated to be 15–20 cm yr–1 for the first five years, 10 cm yr–1 for years 6–10, 5–7 cm yr–1 for years 11–16, and less than 4–5 cm yr–1 thereafter. Males mature at 210–220 cm TL or 14–15 yr of age; females mature at>225 cm TL or 18+ yr of age. The largest male (245 cm TL) was 21.3 yr old; the largest female (268 cm TL) was 24.2 yr old. |
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Keywords: | Chondrichthyes Elasmobranchs Carcharhinidae Ageing methods Growth Vertebral bands Life history |
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