(1 - 2 of 2)
- Ontogenetic vertebral growth patterns in the basking shark Cetorhinus maximus,
- Age and growth of the basking shark Cetorhinus maximus (Gunnerus) was examined using vertebral samples from 13 females (261 to 856 cm total length [TL]), 16 males (311 to 840 cm TL) and 11 specimens of unknown sex (376 to 853 cm TL). Vertebral samples were obtained worldwide from museums and institutional and private collections. Examination of multiple vertebrae from along the vertebral column of 10 specimens indicated that vertebral morphology and band pair (alter-nating opaque and translucent bands) counts changed dramatically along an individual column. Smaller sharks had similar band pair counts along the length of the vertebral column while large sharks had a difference of up to 24 band pairs between the highest and lowest count along the column. Our evidence indicates that band pair deposition may be related to growth and not time in this species and thus the basking shark cannot be directly aged using vertebral band pair counts. © Inter-Research 2008., Cited By (since 1996):9, CODEN: MESED, , , Downloaded from: http://www.int-res.com/abstracts/meps/v361/p267-278/ (13 June 2014).
- Natanson, Wintner, Johansson, Piercy, Campbell, De Maddalena, Gulak, Human, Fulgosi, Ebert, Hemida, Mollen, Vanni, Burgess, Compagno, Wedderburn-Maxwell
- Validated age and growth estimates for the shortfin mako, Isurus oxyrinchus, in the North Atlantic Ocean,
- Age and growth estimates for the shortfin mako, Isurus oxyrinchus, derived from vertebral centra of 258 specimens (118 males, 140 females), ranging in size from 64 to 340 cm fork length (FL) were compared with data from 22 tag-recaptured individuals (74-193 cm FL) and length-frequency data from 1822 individuals (1035 males, 787 females; 65-215 cm FL). Annual band-pair deposition, confirmed by a concurrent bomb radiocarbon validation study, was used as the basis for band interpretation. Validation was further confirmed with a tetracycline-injected male shortfin mako recaptured after being at liberty off South Africa for 1 year and aged at 18 years. Growth rates from tag-recapture analysis (GROTAG) were higher than those derived from vertebral annuli and were only available from sharks up to 193 cm FL at recapture. Modal length-frequency data were used to verify the first four age classes. Growth curves were fit using both von Bertalanffy and Gompertz models. The 3-parameter version of the von Bertalanffy growth function produced the most biologically reasonable values for males, based on observed data (L∞ = 253 cm FL, K = 0.125 year-1 (estimated longevity = 21 year), and L 0 = 72 cm). The 3-parameter version of the Gompertz growth function produced the most biologically reasonable estimates, for females (L ∞ = 366 cm FL, K = 0.087 year-1 (estimated longevity = 38 year) and L0 = 88 cm. Males and females were aged to 29 (260 cm FL) and 32 years (335 cm FL), respectively. Both sexes grew similarly to age 11 (207 cm FL, 212 cm FL for males and females, respectively) when the curve leveled in males and continued to rise in females. Age at 50% maturity was estimated at 8 years for males (185 cm FL) and 18 years for females (275 cm FL). The species grows slower, matures later and has a longer life span than previously reported in North Atlantic waters. © 2006 Springer Science+Business Media, Inc., Cited By (since 1996):30, Fish and Fisheries, CODEN: EBFID, ,
- Natanson, Kohler, Ardizzone, Cailliet, Wintner, Mollet