Age determination and growth of the freshwater catfish, Tandanus tandanus Mitchell, in the Gwydir River, Australia

1977 ◽  
Vol 28 (2) ◽  
pp. 119 ◽  
Author(s):  
TLO Davis
Keyword(s):  
Growth Rates ◽  
Age Determination ◽  
Maximum Size ◽  
Von Bertalanffy ◽  
Freshwater Catfish ◽  
Growth Equations ◽  
Males And Females ◽  
June July

Dorsal spines of T. tandanus from the Gwydir River were used for age determination. Annuli were formed in winter (June-July). The validity of age determination and accuracy of lengths back- calculated from spine radius measurements were supported by tagging data and examination of known age fish. No differences in growth rates were detected between males and females. The variation in growth from season to season was not great. The von Bertalanffy and Gompertz growth equations were used to describe growth in length and weight respectively. The maximum size of catfish in the Gwydir River predicted by these equations was 596 mm and 2605 g.

Age, Growth, and Sexual Maturity of the Shorthorn Sculpin, Myoxocephalus scorpius, in Newfoundland Waters

1970 ◽  
Vol 27 (12) ◽  
pp. 2155-2158 ◽  
Author(s):  
G. P. Ennis
Keyword(s):  
Growth Rates ◽  
Sexual Maturity ◽  
Average Length ◽  
Maximum Size ◽  
Age Group ◽  
Younger Age ◽  
Shorthorn Sculpin ◽  
Males And Females ◽  
The Difference ◽  
Myoxocephalus Scorpius

In Newfoundland waters, shorthorn sculpins, Myoxocephalus scorpius (L.), live to age 15 and attain a maximum size of just over 50 cm. The growth rates of males and females are little different below age 4, but above age 4 the females grow faster than the males, and the difference between average length-at-age for males and females gets progressively larger with age. Males mature at a younger age and at a smaller size than females. In any age-group where there are mature and immature individuals the mature ones are larger.

Age, growth and maturation of the European squid Loligo vulgaris (Myopsida, Loliginidae) on the west Saharan shelf

1995 ◽  
Vol 75 (3) ◽  
pp. 593-604 ◽  
Author(s):  
Alexander Arkhipkin
Keyword(s):  
Life Cycle ◽  
Sexual Dimorphism ◽  
Power Function ◽  
Growth Rates ◽  
Gompertz Function ◽  
The West ◽  
Loligo Vulgaris ◽  
Growth Increments ◽  
Males And Females ◽  
June July

Age, growth and maturation of Loligo vulgaris were studied by examination of growth increments within statoliths of 294 specimens (mantle length, ML, ranging from 31 to 498 mm) caught on the west Saharan shelf between 1985 and 1988. Maximum age was 335 d (290 mm ML) for females, and 396 d (498 mm ML) for males. Growth rates varied considerably among individuals with a greater range in males. Sexual dimorphism in length was apparent after about 210 d. Males and females diverged considerably in weight, with males reaching a greater weight after about 180 d. Growth in length between 124 and 396 d was best described by a power function, while growth in weight was best described by the Gompertz function. Males started maturing at 180–210 d and mature males ranged in age between 250 and 396 d; while females started maturing at 240–270 d and mature females ranged between 285 and 335 d. Loligo vulgaris hatched throughout the year with two distinct peaks; in winter (December - early March) and summer (June-July). The life cycle of L. vulgaris populations on the west Saharan shelf lasts ~1 y, with large males (>450 mm ML) living slightly longer.

Growth ecology of the tree lizard Urosaurus bicarinatus (Squamata: Phrynosomatidae), in a tropical dry forest of the Chamela Region, Mexico

2016 ◽  
Vol 66 (2) ◽  
pp. 189-199 ◽  
Author(s):  
Aurelio Ramírez-Bautista ◽  
Uriel Hernández-Salinas ◽  
J. Gastón Zamora-Abrego
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Growth Rates ◽  
Average Rate ◽  
Growth Patterns ◽  
Dry Forest ◽  
Von Bertalanffy ◽  
Mexican Pacific ◽  
Males And Females ◽  
Tree Lizard

Determination of growth rate provides an important component of an organism’s life history, making estimations of size at maturity, survival rate, and longevity possible. Here, we report on growth rate of males and females of the tropical tree lizard Urosaurus bicarinatus, in a seasonal environment in the state of Jalisco on the Mexican Pacific Coast. We calculated body growth rates and fitted these to the Von Bertalanffy, the logistic-by-length, and the logistic-by-weight growth models. The Von Bertalanffy model provided the best fit, and we used it to analyze the growth pattern. Males and females did not differ in estimated asymptotic size and other characteristic growth parameters. Estimated growth curve predicted an age at maturity of 38 mm SVL on 120 days for males, and 40 mm SVL on 170 days for females. On the basis of the similarities in the growth rates between the sexes, comparisons were made between seasons, and we found that the average rate of growth was slightly, albeit insignificantly, higher in the rainy season than in the dry season. The similarities in the growth patterns for the sexes of this species might be indicative of variance in its life history traits (e.g., fecundity, egg size) compared to those of other populations of this species and other species of this genus; therefore, it is important to document interpopulation differences to understand the evolutionary changes that have led to optimal adaptation in a particular environment more accurately.

scholarly journals Growth rates of the chokka squid Loligo reynaudii d’Orbigny, 1845 (Cephalopoda: Myopsida: Loliginidae) off South Africa, investigated over two years

2021 ◽  
Vol 29 (3) ◽  
Author(s):  
Collette H. Mwanangombe ◽  
Deon Durholtz ◽  
Dawit Yemane ◽  
Jean Githaiga-Mwicigi ◽  
Warwick H. H. Sauer ◽  
...  
Keyword(s):  
South Africa ◽  
Sexual Dimorphism ◽  
Growth Model ◽  
Growth Rates ◽  
Linear Growth ◽  
Maximum Size ◽  
Mantle Length ◽  
Daily Growth ◽  
Males And Females ◽  
Linear Growth Model

Growth of adult chokka squid Loligo reynaudii d’Orbigny was modelled using mantle length and age data derived from samples collected over two years (2003 and 2004) from a single, large cohort of mature and spawning squid. A total of 588 statoliths were examined (310 males, 278 females) from individuals of 71–425 mm mantle length (ML). The maximum size of chokka squid was 425 mm ML for males and 263 mm ML for females. The Francis Growth Model and Linear Growth model were selected for further analysis from six models considered. Males and females attain similar ages, although mantle length-based daily growth rates ranged from 0.75 to 1.02 (0.88 quantile _50) mm/day for males and 0.32–0.45 (0.38 quantile _50) mm/day for females, explaining the sexual dimorphism apparent in the sizes of individuals of this species.

Growth and migration of tagged eastern Australian king prawns, Penaeus plebejus Hess

1987 ◽  
Vol 38 (2) ◽  
pp. 225 ◽  
Author(s):  
JP Glaister ◽  
T Lau ◽  
VC McDonall
Keyword(s):  
Growth Rates ◽  
Growth Parameters ◽  
New South ◽  
Maximum Size ◽  
East Australian Current ◽  
Von Bertalanffy ◽  
South Wales ◽  
Apparent Relationship ◽  
And Migration ◽  
Related Mortality

Growth rates and migration of P. plebejus were investigated by a series of tagging experiments. Growth records of 157 recaptured, streamer-tagged prawns from 2450 releases were analysed for estimates of von Bertalanffy growth parameters by Fabens method. The size-age relationship differed between sexes with males attaining only 75% of the maximum size of female prawns. There was no appreciable size-related mortality of tagged individuals. Recaptured tagged prawns confirmed the previously determined northerly movement and showed little movement toward deeper water off New South Wales. Once past the easternmost point of the continent dispersal into a range of depths occurred. There was no apparent relationship between rates of movement and size, suggesting that fluctuations in the intensity of the East Australian Current were responsible for variations in these rates. Based on the results of this and other tagging studies, a two-substock hypothesis, defined by the origins of the bulk of recruits, is postulated.

Growth of the abalone Haliotis roei gray

1989 ◽  
Vol 40 (2) ◽  
pp. 199 ◽  
Author(s):  
JK Keesing ◽  
FE Wells
Keyword(s):  
Growth Model ◽  
Growth Rates ◽  
Maximum Size ◽  
Growth Characteristics ◽  
Minimum Size ◽  
First Year ◽  
Von Bertalanffy ◽  
Commercial Fishery ◽  
Von Bertalanffy Growth Model ◽  
Second Year

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.

Age determination and growth of the smalltail shark, Carcharhinus porosus, from northern Brazil

1998 ◽  
Vol 49 (7) ◽  
pp. 705 ◽  
Author(s):  
Rosangela Lessa ◽  
Francisco Marcante Santana
Keyword(s):  
Growth Parameters ◽  
General Pattern ◽  
Age Determination ◽  
Age And Growth ◽  
Von Bertalanffy ◽  
Length Frequency ◽  
Northern Brazil ◽  
Late Maturity ◽  
Males And Females ◽  
Length Frequency Data

Age and growth of C. porosus was estimated from seasonally formed marks in vertebrae of 504 specimens (30.0–101.0 cm total length), and from length–frequency data from 1128 individuals (29.4–120.5 cm). Estimated von Bertalanffy growth parameters were: from observed length-at-age, L∞ 125.1 cm, K 0.101 year-1 and t0 –2.89 year; from back-calculated lengths, L∞ 136.4 cm, K 0.077 year-1, t0 –3.27 year; and from length–frequency analysis, L∞ 131.0, K 0.080 and t0 –3.40. Growth did not differ significantly between sexes. Males and females were mature at 71.0 and 70.0 cm, respectively, corresponding to 6 years old. The largest shark aged from vertebrae was a 12-year-old female (101.0 cm). Growth rates calculated from mean observed lengths were 7.0 cm year-1 for the first four years and 4.0 cm year-1 after maturity. Lee’s phenomenon was not apparent. The annulus forms from September to January. Parameters derived from back-calculated lengths were considered to best describe growth. Like most carcharhinids, C. porosus follows the general pattern of K-selected species, exhibiting slow growth, late maturity and low fecundity. Resumo. A idade e o crescimento de C. porosus foram estimados a partir de marcas sazonais em vértebras de 504 indivíduos (30.0–101.0 cm comprimento total) e através de distribuição de freqÜências de comprimentos de 1128 indivíduos (29.4–120.5 cm). Os parâmetros de von Bertalanffy obtidos com comprimentos observados na captura foram: L∞ 125.1 cm, K 0.101 ano –1 e t0 –2.89 anos; com comprimentos retrocalculados: L∞ 136.4 cm, K 0.077 ano-1, t0 –3.27 anos, e da distribuição de freqÜências de comprimentos obteve-se: L∞ 131.0 cm, K 0.080 ano-1 e t0 –3.40. O crescimento não difere entre sexos. Machos e fêmeas são maduras com 71 e 70 cm, respectivamente, correspondendo a idade de 6 anos. O maior espécime cuja idade foi estimada das vértebras tinha 12 anos (101.0 cm). As taxas de crescimento calculadas dos comprimentos médios observados foram 7.0 cm ano-1 para os primeiros quatro anos e 4.0 cm ano-1 após a maturidade. O fenômeno de Lee não ocorreu. O anel se forma entre setembro e janeiro. Os parâmetros obtidos do retroclculo descreveram melhor o crescimento. Como muitos carcharhinideos, C. porosus segue o padrão das espécies da seleção K, exibindo crescimento lento, maturidade tardia e baixa fecundidade.

Age, growth and maturity of a New Zealand endemic shark (Mustelus lenticulatus) estimated from vertebral bands

2000 ◽  
Vol 51 (1) ◽  
pp. 35 ◽  
Author(s):  
Malcolm P. Francis ◽  
Caoimhghin Ó Maolagáin
Keyword(s):  
Growth Rates ◽  
East Coast ◽  
Growth Curves ◽  
Von Bertalanffy ◽  
Frequency Data ◽  
Length Frequency ◽  
Significant Difference ◽  
Growth Bands ◽  
Males And Females ◽  
Length Frequency Data

Rig (Mustelus lenticulatus) specimens were aged by counting growth bands in whole vertebrae that were illuminated laterally with fibre-optic lights. Bands were counted by two readers who used information on the diameter of the vertebrae of new-born young and 1-year-old juveniles to identify the inner bands. The greatest estimated age was 12.1 years for a female of 137 cm total length, but few rig were more than 8 years old. For west coast South Island (WCSI) rig, there was no significant difference in growth rates of males and females. After pooling both sexes, there was no significant difference in growth rates between WCSI and east coast South Island (ECSI) rig. The combined WCSI and ECSI von Bertalanffy growth curve was Lt = 147.2 (1 – e −0.119[t + 2.35]). This curve agreed well with growth curves derived from length–frequency data, but validation of the ageing technique is still required. WCSI males mature at ~85 cm and 5–6 years, and females at ~100 cm and 7–8 years. ECSI rig probably mature at similar lengths and ages. Tagged rig have been recaptured after nearly 14 years at liberty. Longevity probably exceeds 15 years, and may exceed 20 years.

scholarly journals PÜLÜMÜR NEHRİ'NDE YAŞAYAN Acanthobrama marmid Heckel, 1843 POPULASYONUNUN BAZI BÜYÜME ÖZELLİKLERİNİN BELİRLENMESİ

2020 ◽  
Vol 15 (4) ◽  
pp. 121-133
Author(s):  
Ebru İfakat Özcan
Keyword(s):  
Condition Factor ◽  
Growth Parameters ◽  
Age Groups ◽  
Age Determination ◽  
Von Bertalanffy ◽  
Allometric Growth ◽  
Sex Distribution ◽  
Male Ratio ◽  
Growth Equations ◽  
Growth Features

In this study, some growth features have been investigated like sex distribution, length and weight relationship, age determination, von Bertalanffy growth parameters and condition factor of population Acanthobrama marmid Heckel, 1843 in Pülümür River. 276 samples examined during the study consisted of 157 females and 119 males and the female/male ratio was calculated as 1/0.758. It was determined that the total length and weight values varied between 7.8-21.1cm and 5.6-121.21 g in all individuals. The population has showed distribution between I-V age groups. Length-weight equation in were determined as W=0.0063L3.248 (R2=0.960) in females, W=0.0062L3.252 (R2=0.958) in males and W=0.0063L3.249 (R2=0.959) in all individuals. Positive allometric growth was observed for both sexes due to the “b” values were statistically different from 3. The von Bertalanffy growth equations were determined Lt=27.00 [1–e–0.247(t+0.876)] and Wt =249.66 [1-e–0.247(t+0.876)]3.248 for female, Lt=27.55 [1–e–0.232(t+0.952)] and Wt=280.02 [1–e–0.232(t+0.952)]3.252 for male, Lt=27.34 [1–e–0.238(t+0.916)] and Wt=261.55 [1–e–0.238(t+0.916)]3.249 for all individuals. Growth performance index (Ф') value was calculated as 2.250 for all individuals. Condition factor varies between 0.548-1.653 in female and 0.567-1.670 in male. It was observed that the value of the condition factor generally increased with age.

Seasonal Variation of Suicide in the City of São Paulo, Brazil, 1996–2010

Crisis ◽  
2014 ◽  
Vol 35 (1) ◽  
pp. 5-9 ◽  
Author(s):  
Daniel Hideki Bando ◽  
Fernando Madalena Volpe
Keyword(s):  
Seasonal Pattern ◽  
Total Sample ◽  
Sao Paulo ◽  
Seasonal Patterns ◽  
São Paulo ◽  
Health Statistics ◽  
Males And Females ◽  
June July ◽  
The City ◽  
Over Time

Background: In light of the few reports from intertropical latitudes and their conflicting results, we aimed to replicate and update the investigation of seasonal patterns of suicide occurrences in the city of São Paulo, Brazil. Methods: Data relating to male and female suicides were extracted from the Mortality Information Enhancement Program (PRO-AIM), the official health statistics of the municipality of São Paulo. Seasonality was assessed by studying distribution of suicides over time using cosinor analyses. Results: There were 6,916 registered suicides (76.7% men), with an average of 39.0 ± 7.0 observed suicides per month. For the total sample and for both sexes, cosinor analysis estimated a significant seasonal pattern. For the total sample and for males suicide peaked in November (late spring) with a trough in May–June (late autumn). For females, the estimated peak occurred in January, and the trough in June–July. Conclusions: A seasonal pattern of suicides was found for both males and females, peaking in spring/summer and dipping in fall/winter. The scarcity of reports from intertropical latitudes warrants promoting more studies in this area.

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