Age and Growth of Dogfish Squalus acanthias in British Columbia Waters

1975 ◽  
Vol 32 (1) ◽  
pp. 43-59 ◽  
Author(s):  
K. S. Ketchen

Ages of dogfish have been determined from markings on the second dorsal spine by a technique that enables use of badly worn spines from relatively large fish to correct for the tendency to underestimate age. While the technique may have led to slight overestimation of age, particularly of dogfish from Hecate Strait, there is some corroborating evidence for the Strait of Georgia drawn from length-frequency distributions, sizes of fish in relation to reproductive stages, and assumptions about the average annual net uptake of mercury. It is tentatively concluded that the growth curve for females, expressed in terms of the von Bertalanffy equation, has parameters of K = 0.048, [Formula: see text], and t0 = −4.88 yr. Parameters suggested for males are: K = 0.070, [Formula: see text], and t0 = −4.70 yr. The implication emerging from these results is that females and males on the average take 23 yr and 14 yr, respectively, to reach maturity.

2000 ◽  
Vol 51 (4) ◽  
pp. 339 ◽  
Author(s):  
Rosangela Lessa ◽  
Francisco M. Santana ◽  
Vandick Batista ◽  
Zafira Almeida

Age and growth of the daggernose shark, Isogomphodon oxyrhynchus, from northern Brazil were determined from 105 vertebral sections stained with alizarin red-S representing 46 males, 52 females and 7 specimens of unknown sex (58.4 to 141 cm-TL) and verified with length–frequency analysis of 1135 specimens (632 females and 503 males, 58–160 cm ). Marginal increments did not show significant differences throughout the year, and it was assumed that one band is formed annually. Different tests provided varying results for growth curve comparisons between sexes; the curves were similar, despite biological differences. von Bertalanffy growth parameters estimated from back-calculated mean lengths, observed mean lengths-at-age and length–frequency analysis were of the same magnitude. Parameters generated from observed length-at-age were chosen for describing growth for the species: L• 171.4 cm, k 0.12 year –1 and t0 –2.612 years. The largest female aged from vertebrae was 12 years old, whereas the largest male was aged at 7 years. Neonates, ~42.3 cm, showed one band in the vertebrae, formed at birth, or soon thereafter. Males are mature at 103 cm or 5–6 years and females at 115 cm or 6–7 years. Resumo. A idade e o crescimento do cação quati, Isogomphodon oxyrhynchus, do norte do Brasil foi determinada usando 105 vértebras seccionadas e coradas com alizarina vermelha-S de 46 machos, 52 fêmeas e 7 exemplares de sexo indeterminado (58,4–141 cm-CT). Análise de distribuição de frequência de comprimentos de 1135 indivíduos (632 femeas e 503 machos, 58–160 cm) foi utilizada como método de verificação. Os incrementos marginais não mostraram diferenças significativas ao longo do ano, assumindo-se que uma banda é formada anualmente. Com diferentes testes, usados para comparar curvas de crescimento entre os sexos, obteve-se resultados conflitantes; o crescimento foi considerado idêntico entre os sexos, apesar das diferenças biológicas entre machos e fêmeas. Os parâmetros de von Bertalanffy estimados do retrocálculo, comprimentos médios observados e da análise de comprimentos foram semelhantes, tendo sido escolhidos para descrever o crescimento da espécie: L• 8171,4 cm; k 0,12 year –1 et 0 –2,612 years. Amaior fêmea cuja idade foi estimada pelas vértebras tinha 12 anos enquanto o maior macho tinha 7 anos. Recém-nascidos de 42,3 cm apresentavam uma banda nas vertebras, formada ao nascer, ou logo depois do nascimento. Machos estão maduros em 103 cm ou 5–6 anos e fêmeas em 115 cm ou 6–7 anos.


1988 ◽  
Vol 39 (4) ◽  
pp. 417 ◽  
Author(s):  
S Davenport ◽  
JD Stevens

The age and growth of Carcharhinus tilstoni and C. sorrah, the two most abundant shark species in commercial gill-net catches off northern Australia, were investigated by the examination of vertebral rings. Corroborating evidence for age and growth estimates was obtained from length-frequency distributions and tag-recapture data. To aid validation of these estimates, tetracycline was injected into sharks at the time of tagging. Growth is relatively rapid in the first year of life: vertebral ageing indicated 17 cm growth in total length (TL) for C. tilstoni and about 20 cm for C. sorrah during the first year after birth. By the time the sharks are 5 years old, growth has declined to 8-10 cm per year in C. tilsoni and 5 cm per year or less in C. sorrah. The von Bertalanffy growth parameters for C. tilstoni are L∞ = 194.2, K = 0.14, t0 = -2.8 for females, and L∞ = 165.4, K = 0.19, t0 = -2.6 for males; for C. sorrah the parameters are L∞ = 123.9, K = 0.34, t0 = -1.9 for females, and L∞ = 98.4, K = 1.17, t0 = -0.6 for males. The greatest recorded ages for C. tilstoni were 12 years for females and 8 years for males, and for C. sorrah, 7 years for females and 5 years for males. Sexual maturity is reached early: at 3 to 4 years in C. tilstoni and 2 to 3 years in female C. sorrah.


Author(s):  
L.J.L. Lumingas ◽  
M. Guillou

A procedure for accurately determining age and growth of the sea urchin Sphaerechinus granularis (Lamarck) (Echinodermata: Echinoidea) in the Bay of Brest (France) is described. Readings of growth lines were made from the longitudinal cross-section of interambulacral oral plates of sea urchins collected in February 1993. These results agree with age estimates calculated using the ELEFAN I programme based on diameter-frequency distributions of sea urchins collected from February 1992 to March 1993. A non-linear regression (monomolecular equation) best describes the relationship between test diameter and plate thickness. The diameter-at-age data can be increased by back-calculation, assuming a constant proportional deviation from the mean size of the test. Although von Bertalanffy growth curves fitted to actual observations were similar to those fitted to back-calculated diameter-at-age data, the latter produced a more adequate curve and increased the quality of the growth parameter estimators. The von Bertalanffy growth curve estimated by ELEFAN I shows a pattern similar to the back-calculated von Bertalanffy growth curve.


Author(s):  
Alexander I. Arkhipkin ◽  
Vladimir V. Laptikhovsky

Length composition, maturation and growth of the ommastrephid squid Todaropsis eblanae were studied using length–frequency distributions (LFDs) and statoliths of squid caught off the north-west African coast. Length–frequency distributions were quite similar in all seasons studied, indicating all year round spawning. However, both high proportions of mature squid in the winter and the hatching peak of squid from our sample in spring suggested the winter–spring peak of spawning. Immature and maturing squid had rather high growth rates, attaining 140—150 mm of dorsal mantle length (ML) by the age of 160—170 d. Todaropsis eblanae is likely to have an annual life cycle on the north-west African shelf.


1982 ◽  
Vol 33 (2) ◽  
pp. 245 ◽  
Author(s):  
DC Smith

N. macropterus, landed at the port of Eden, were sampled from July 1976 to June 1979. Saggital otoliths were used for age determination. A hyaline and an opaque ring were found to be formed during winter and summer. respectively. The growth of adult N. macropterus was adequately described by the von Bertalanffy growth curve. Females (K = 0.13, L∞ = 51.13) were found to grow faster, and to a greater age, than males (K = 0.17. L∞ = 45.50). No significant difference between sexes was apparent in the length-weight relationships.


2021 ◽  
Vol 19 (2) ◽  
Author(s):  
Leandro Balboni ◽  
Facundo Vargas ◽  
Darío Colautti

Abstract The age and growth of Pseudoplatystoma corruscans, is analyzed on specimens landed in Puerto Antequera, Province of Chaco, Argentina. The study is based on length frequency distribution of 1192 individuals and growth marks of 293 pectoral spines. Previously to age assignation based on spines readings, we performed analyses that ruled out age-associated resorption of rings and corroborated the annual periodicity of mark formation. The average sizes of the radius of each ring were obtained, and the total length of fish were back-calculated to the time of the ring formation, by the regression model fitted between the total radius of the spines to the respective sizes of each fish. Such data showed a good fitting to growth models of von Bertalanffy, Gompertz and logistic for both sexes separately. Results indicate that the study of the species growth must be carried out for each sex separately and that the fishing regulations must consider this characteristic of the species since the current management guidelines could be promoting differential capture by sexes.


1999 ◽  
Vol 50 (2) ◽  
pp. 103 ◽  
Author(s):  
P. L. Horn ◽  
R. J. Hurst

Age determination of gemfish by counting hyaline zones in otoliths was validated by following the progression of modes in length–frequency distributions and the progression of strong and weak year classes in age–frequency distributions. Length–frequency and otolith samples were examined from four areas (west Northland, east Northland and Bay of Plenty, Wairarapa coast, and the Stewart- Snares shelf). Age–frequency distributions and von Bertalanffy growth parameters were calculated and compared between areas. Two gemfish stocks are indicated on the basis of patterns of year class strengths, trends in commercial landings and likely spawning areas; one off the east and north of the North Island, and another off the west and south of the South Island. Estimates of natural mortality are presented for the two stocks.


2018 ◽  
Vol 20 (1) ◽  
pp. 85-90 ◽  
Author(s):  
GOPALAN MAHADEVAN ◽  
PALANIVEL BHARATHIRAJAN ◽  
VELAYUTHAM RAVI ◽  
MOJTABA POULADI ◽  
MARYAM MIRZAEI VAND KHANGHAH

Mahadevan G, Bharathirajan P, Ravi V, Pouladi M, Mirzaei Vand Khanghah M. 2019. Short Communication: Age and growth of elongated mudskipper, Pseudapocryptes elongatus (Cuvier, 1816) from Sundarbans, India. Biodiversitas 20: 85-90. The estimation of age and mathematical expression of fish growth is complex and debated subject in fishery sciences. Growth parameters of elongated mudskipper, Pseudapocryptes elongatus were estimated based on the length frequency data using FiSAT II software (several tools such as Powell-Wetherall method, ELEFAN and von Bertalanffy growth estimates). Samples were collected from Sundarbans mangroves using gill and cast nets and by hand picking. The length-frequency (LFQ) of P.elongatus was recorded from January 2014 to December 2015 and the above tools estimated the growth parameters (L∞, K and t0) from the progression of LFQ modes through time. L∞ and K values of males were 220.50 mm and 1.3 yr-1, respectively and similarly, L∞ and K values of females were 221.05 mm and 1.21 yr-1, respectively. The t0 values estimated for males and females were-0.1915 years and-0.1661 years, respectively. The estimated growth performance index (Φ) values for males and females of P. elongatus were 4.394 and 4.503, respectively. The lifespan of both the sexes was found to be 4+ years.


1983 ◽  
Vol 34 (3) ◽  
pp. 451 ◽  
Author(s):  
TM Berra ◽  
PL Cadwallader

The age and growth of Australian grayling were studied in 1203 individuals collected from the Tambo River, Victoria, between January and November 1979. Scales from 667 grayling were examined. The scale method of age determination was validated by the analysis of seasonal changes in the pattern of scale growth and by correspondence between ages inferred from length-frequency distributions and ages determined by scale readings. One annulus is formed on the scale by October. Most (88%) grayling belonged to the 1+ and 2+ age-classes; fish aged 3+ and 4+ made up 11% of the collection, and fish aged 5+ less than 1%. Size increased from January until May; growth ceased during winter and resumed in September. There was no difference in growth between the sexes. The largest grayling collected was a female of 253 mm fork length (Lf). The overall length-weight relationship was W = 2 715 × 10-6Lf3 2764. The relationship between total length (Lt) and Lf was Lt = 0.93 16 + 1.0742 Lf, and between standard length (Ls) and Lf was Ls = 0.8007 + 0.9095 Lf The overall ratio of males to females was 56 : 44.


2004 ◽  
Vol 61 (2) ◽  
pp. 292-306 ◽  
Author(s):  
J Paige Eveson ◽  
Geoff M Laslett ◽  
Tom Polacheck

A maximum likelihood method for modelling fish growth is presented that integrates data from three key sources of growth information: tag–recapture studies, length–frequency samples from commercial catches, and direct aging data from hard-parts analyses. Previous studies have almost exclusively modelled growth using only one of these sources of information. Different data sources are often most informative about different portions of the life cycle. The development of an integrated approach allows for the different data sources to complement each other and provide more comprehensive and robust estimates of growth parameters. The integrated method is applied to data sets from southern bluefin tuna (Thunnus maccoyii) using the von Bertalanffy growth curve as well as a more sophisticated growth curve that makes a smooth transition between two von Bertalanffy curves with different growth rate parameters. The latter is found to provide a significantly better fit and supports previous findings that southern bluefin tuna experience a transition in growth during the juvenile stage of life. Many species exhibit a seasonal growth pattern, including southern bluefin tuna for which growth is fastest during the austral summer. A method for incorporating an annual seasonal component into the analysis is described and applied.


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