Maturity and growth characteristics of a commercially exploited stingray, Dasyatis dipterura

2007 ◽  
Vol 58 (1) ◽  
pp. 54 ◽  
Author(s):  
Wade D. Smith ◽  
Gregor M. Cailliet ◽  
Everardo Mariano Melendez

Maturity and growth characteristics were estimated for Dasyatis dipterura from western Mexico, where it is a common component of artisanal elasmobranch fisheries. Median disc width at maturity was estimated as 57.3 cm for females (n = 126) and 46.5 cm for males (n = 55) respectively. Age estimates were obtained from 304 fishery-derived specimens (169 female, 135 male). An annual pattern of band-pair deposition was validated through modified centrum edge and marginal increment analyses. Gompertz, polynomial and von Bertalanffy growth models were fit to disc width and weight-at-age data. Resulting models were evaluated based on biological rationale, standard error of model estimates, and Akaike’s information criteria. Growth characteristics differed significantly between females and males. Maximum age estimates were 28 years for females and 19 years for males. Three-parameter von Bertalanffy growth models of disc width-at-age data generated the most appropriate fits and produced relatively low estimates of instantaneous growth rates for females (DW∞ = 92.4 cm, k = 0.05, t0 = –7.61, DW0 = 31.4 cm) and males (DW∞ = 62.2 cm, k = 0.10, t0 = –6.80, DW0 = 31.3 cm). These values are the lowest reported for myliobatiform stingrays and indicate slow growth rates in comparison with elasmobranchs in general.


2012 ◽  
Vol 90 (8) ◽  
pp. 915-931 ◽  
Author(s):  
S.C. Lubetkin ◽  
J.E. Zeh ◽  
J.C. George

We used baleen lengths and age estimates from 175 whales and body lengths and age estimates from 205 whales to test which of several single- and multi-stage growth models best characterized age-specific baleen and body lengths for bowhead whales ( Balaena mysticetus L., 1758) with the goal of determining which would be best for predicting whale age based on baleen or body length. Previous age estimates were compiled from several techniques, each of which is valid over a relatively limited set of physical characteristics. The best fitting single-stage growth model was a variation of the von Bertalanffy growth model for both baleen and body length data. Based on Bayesian information criterion, the two- and three-stage versions of the von Bertalanffy model fit the data better than did the single-stage models for both baleen and body length. The best baleen length models can be used to estimate expected ages for bowhead whales with up to 300–325 cm baleen, depending on sex, which correspond to age estimates approaching 60 years. The best body length models can be used to estimate expected ages for male bowhead whales up to 14 m, and female bowheads up to 15.5 m or ages up to approximately 40 years.



1988 ◽  
Vol 45 (6) ◽  
pp. 936-942 ◽  
Author(s):  
R. I. C. C. Francis

The two most common ways of estimating fish growth use age–length data and tagging data. It is shown that growth parameters estimated from these two types of data have different meanings and thus are not directly comparable. In particular, the von Bertalanffy parameter l∞ means asymptotic mean length at age for age–length data, and maximum length for tagging data, when estimated by conventional methods. New parameterizations are given for the von Bertalanffy equation which avoid this ambiguity and better represent the growth information in the two types of data. The comparison between growth estimates from these data sets is shown to be equivalent to comparing the mean growth rate of fish of a given age with that of fish of length equal to the mean length at that age. How much these growth rates may differ in real populations remains unresolved: estimates for two species of fish produced markedly different results, neither of which could be reproduced using growth models. Existing growth models are shown to be inadequate to answer this question.



1989 ◽  
Vol 40 (2) ◽  
pp. 199 ◽  
Author(s):  
JK Keesing ◽  
FE Wells

The growth characteristics of the abalone Haliotis roei from Western Australia are described. Abalone grow rapidly to over 40 mm in their first year. In their second year, they reach 60 mm, the minimum size that can be legally taken by amateur fishermen. They are recruited to the commercial fishery at 70 mm during their third year. The parameters of the von Bertalanffy growth model were K = 0.67 year-1 and L∞ = 85.2 mm; however, differences occur between intertidal and subtidal habitats, with abalone of the subtidal population achieving faster growth rates and a larger maximum size. No significant differences in growth were detected between sexes.



2012 ◽  
Vol 69 (11) ◽  
pp. 1850-1869 ◽  
Author(s):  
Allen H. Andrews ◽  
Edward E. DeMartini ◽  
Jon Brodziak ◽  
Ryan S. Nichols ◽  
Robert L. Humphreys

Growth characteristics of Pristipomoides filamentosus, a deepwater eteline snapper of major economic importance, are incomplete and inconsistent across its geographical range. Early growth rates have been validated using daily increment and length–frequency analyses, but historical estimates of adult growth rates are variable and longevity is unknown. Studies of P. filamentosus in the Hawaiian Islands have cautioned against unjustified estimates of longevity, but 18 years has at times been uncritically assumed as the maximum age. The present study addresses these age, growth, and longevity issues using lead–radium and bomb radiocarbon dating by providing valid age estimates for adult P. filamentosus. Valid length-at-age estimates ranged from approximately 10 years to more than 40 years. These data, together with robust daily increment data, were used to model a fully validated, long-lived life history for P. filamentosus. This study adds to the few existing studies supporting a view that many tropical fishes, particularly deepwater species, can be longer lived than previously surmised.



2021 ◽  
Vol 51 (4) ◽  
pp. 371-378
Author(s):  
Penprapa Phaeviset ◽  
Pisit Phomikong ◽  
Piyathap Avakul ◽  
Sontaya Koolkalaya ◽  
Wachira Kwangkhang ◽  
...  

The spotted catfish, Arius maculatus (Thunberg, 1792), is a euryhaline fish that is economically important in the Indo-West Pacific. Population dynamics studies and stock assessments of this species have focused on marine stocks, but not those from fresh water. In this study, the age and growth of A. maculatus were, therefore, investigated for the inland stock in Songkhla Lake, Thailand. A total of 213 individuals ranging between 35 and 238 mm TL were used. The length–weight relation indicated positive allometry of this population. Three hard parts (otolith, dorsal- and pectoral-fin spines) were used for aging. The marginal increment ratio confirmed that an annulus was deposited once a year in all three hard parts. All of the samples were aged between 0+ and 6+ years. Verification of age estimates from three readers showed that the otolith was the most suitable part for age estimation. Three growth models (von Bertalanffy, Gompertz, and logistic) were applied in the study. The von Bertalanffy model best described the growth of this fish in Songkhla Lake. The obtained asymptotic length was 290.87 mm TL and the relative growth rate parameter was 0.166 year–1. Our results will be applied as inputs for fish stock assessment models. The obtained growth parameters also can serve as a reference for A. maculatus stocks elsewhere.



2012 ◽  
Vol 63 (1) ◽  
pp. 23 ◽  
Author(s):  
Fay Helidoniotis ◽  
Malcolm Haddon

Accurate estimates of marine organism growth are important for modelling the dynamics of populations and rely on the selection of an appropriate growth model. However, there is no assurance that the statistically optimum model will also be biologically plausible. Three growth models (von Bertalanffy, Gompertz and a linear model) were fitted to a dataset consisting of two cohorts of juvenile size classes of blacklip abalone (Haliotis rubra). Results show that the non-seasonal Gompertz was statistically better than the non-seasonal von Bertalanffy and linear models. There was a persistent seasonal signal through the juvenile size range, with slow growth in winter and fast growth during summer. When a seasonal term was formally incorporated, the model fits were greatly improved, particularly for the linear and von Bertalanffy models. The seasonal-Gompertz predicted growth rates that were biologically implausible for juveniles of 2 mm shell length; 107 μm day–1 for one cohort and 24 μm day–1 for the other. These rates are inconsistent with published growth rates observed under both controlled and wild conditions. In contrast, the seasonal-linear model predicted growth rates of 60 μm day–1 for animals of 2 mm shell length, consistent with published findings. The selection of a growth model based solely on statistical criteria may not take into account the complex processes that influence growth of juveniles.



Author(s):  
Silvina Botta ◽  
Eduardo R. Secchi ◽  
Mônica M.C. Muelbert ◽  
Daniel Danilewicz ◽  
Maria Fernanda Negri ◽  
...  

Age and length data of 291 franciscana dolphins (Pontoporia blainvillei) incidentally captured on the coast of Rio Grande do Sul State (RS), southern Brazil, were used to fit growth curves using Gompertz and Von Bertalanffy growth models. A small sample of franciscanas (N = 35) from Buenos Aires Province (BA), Argentina, were used to see if there are apparent growth differences between the populations. Male and female franciscana samples from both areas were primarily (78–85%) <4 years of age. The Von Bertalanffy growth model with a data set that excluded animals <1 year of age provided the best fit to data. Based on this model, dolphins from the RS population reached asymptotic length at 136.0 cm and 158.4 cm, for males and females, respectively. No remarkable differences were observed in the growth trajectories of males and females between the RS and BA populations.



2009 ◽  
Vol 57 (4) ◽  
pp. 273-285 ◽  
Author(s):  
Marcelo Francisco de Nóbrega ◽  
Rosangela Paula Lessa

Age and growth of the king mackerel (Scomberomorus cavalla) were estimated for northeastern Brazil. A total of 405 sagittal otoliths from 140 males (24.4-112 cm), 73 females (28-114.8 cm) and 193 specimens of unknown sex (11.5-121 cm) were examined. Marginal increment analysis indicated an annual pattern for growth band deposition. The age classes ranged from 1 to 15 years. Length ranged from 11.5 to 121 cm. The Schnute model indicated that the von Bertalanffy growth model demonstrated the best adjustment, with p=1/b, and was therefore used for estimating growth. Back-calculated curves had smaller variances, giving the following estimated growth parameters for males: L∞= 116.8 cm, K = 0.190, t0 = 0.377; and females: L∞= 132.7 cm, K = 0.159 and t0 = 0.387. In order to compare the curves for males and females, the overlapping of 95% confidence intervals was performed for the parameters generated from the von Bertalanffy non-linear least square method. Specimens between 3 and 8 years of age represented 82.2% (n=5,783) of the catch composition, characterizing the species as a catchable stock in the region.



2017 ◽  
Vol 81 (2) ◽  
pp. 308-315 ◽  
Author(s):  
Vijay K. Juneja ◽  
Abhinav Mishra ◽  
Abani K. Pradhan

ABSTRACT Kinetic growth data for Bacillus cereus grown from spores were collected in cooked beans under several isothermal conditions (10 to 49°C). Samples were inoculated with approximately 2 log CFU/g heat-shocked (80°C for 10 min) spores and stored at isothermal temperatures. B. cereus populations were determined at appropriate intervals by plating on mannitol–egg yolk–polymyxin agar and incubating at 30°C for 24 h. Data were fitted into Baranyi, Huang, modified Gompertz, and three-phase linear primary growth models. All four models were fitted to the experimental growth data collected at 13 to 46°C. Performances of these models were evaluated based on accuracy and bias factors, the coefficient of determination (R2), and the root mean square error. Based on these criteria, the Baranyi model best described the growth data, followed by the Huang, modified Gompertz, and three-phase linear models. The maximum growth rates of each primary model were fitted as a function of temperature using the modified Ratkowsky model. The high R2 values (0.95 to 0.98) indicate that the modified Ratkowsky model can be used to describe the effect of temperature on the growth rates for all four primary models. The acceptable prediction zone (APZ) approach also was used for validation of the model with observed data collected during single and two-step dynamic cooling temperature protocols. When the predictions using the Baranyi model were compared with the observed data using the APZ analysis, all 24 observations for the exponential single rate cooling were within the APZ, which was set between −0.5 and 1 log CFU/g; 26 of 28 predictions for the two-step cooling profiles also were within the APZ limits. The developed dynamic model can be used to predict potential B. cereus growth from spores in beans under various temperature conditions or during extended chilling of cooked beans.





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