Age and growth of Neotrygon picta, Neotrygon annotata and Neotrygon kuhlii from north-east Australia, with notes on their reproductive biology

Vertebral band formations were used to define age and growth in three Neotrygon species caught regularly as by-catch in prawn trawl fisheries in north-east Australia. Centrum edge and marginal increment ratio analyses were used to validate annual band formations. Age estimates ranged from 1 to 18 years, with the von Bertalanffy growth function considered to have the best fit to Neotrygon picta (males, W(D∞) = 271 mm, k = 0·12; females, W(D∞) = 360·5 mm, k = 0·08) and Neotrygon kuhlii (males, W(D∞) = 438·6 mm, k = 0·08; females, W(D∞) = 440·6 mm, k = 0·08) disc width (W(D))-at-age data. The Gompertz growth function had the best fit to Neotrygon annotata W(D)-at-age data (males, W(D∞) = 230·4 mm, k = 0·20; females, W(D∞) = 265·5 mm, k = 0·31). Age at sexual maturity ranged from 3 to 6 years, with N. picta having the smallest size at birth (100 mm W(D)), smallest W(D) at 50% maturity (W(D50): male, 172 mm, female, 180·7 mm) and lowest age at sexual maturity (3-4 years). This study helps redefine and improve the accuracy of fisheries-based risk assessments for these small species with relatively conservative life-history variables.     

The life histories of endangered hammerhead sharks (Carcharhiniformes, Sphyrnidae) from the east coast of Australia

The life histories of two globally endangered hammerhead sharks, Sphyrna lewini and Sphyrna mokarran, were examined using samples collected from a range of commercial fisheries operating along the east coast of Australia. The catch of S. lewini was heavily biased towards males, and there were significant differences in von Bertalanffy growth parameters (L(∞) and k) and maturity [stretched total length (L(ST)) and age (A) at which 50% are mature, L(ST50) and A(50)] between those caught in the tropics (L(∞) = 2119 mm, k = 0·163, L(ST50) = 1471 mm, A(50) = 5·7 years) and those caught in temperate waters (L(∞) = 3199 mm, k = 0·093, L(ST50) = 2043 mm, A(50) = 8·9 years). The best-fit estimates for a three-parameter von Bertalanffy growth curve fit to both sexes were L(∞) = 3312 mm, L(0) = 584 mm and k = 0·076. Males attained a maximum age of 21 years and grew to at least 2898 mm L(ST). The longevity, maximum length and maturity of females could not be estimated as mature animals could not be sourced from any fishery. Length at birth inferred from neonates with open umbilical scars was 465-563 mm L(ST). There was no significant difference in length and age at maturity of male and female S. mokarran, which reached 50% maturity at 2279 mm L(ST) and 8·3 years. Sphyrna mokarran grew at a similar rate to S. lewini and the best-fit estimates for a two-parameter von Bertalanffy equation fit to length-at-age data for sexes combined with an assumed mean length-at-birth of 700 mm were L(∞) = 4027 mm and k = 0·079. Females attained a maximum age of 39·1 years and grew to at least 4391 mm L(ST). The oldest male S. mokarran was 31·7 years old and 3691 mm L(ST). Validation of annual growth-band deposition in S. mokarran was achieved through a mark, tag and recapture study.     

Reproductive biology and implications for management of the painted sweetlips Diagramma pictum in the southern Arabian Gulf

The reproductive biology of the painted sweetlips Diagramma pictum was determined from 487 individuals collected between January and December 2010 in the southern Arabian Gulf. There was no evidence of sex change and the combination of histological results with the sex composition of the size and age structures indicated a gonochoristic sexual pattern. There were peaks in gonado-somatic indices for females in March and October with spawning occurring during two seasons (April to May and November). The mean size and age at sexual maturity (L(m50) and A(m50) ) were 35·7 cm fork length (L(F) ) and 2·9 years for females and 26·7 cm L(F) and 0·5 years for males. The maximum recorded age (11 years) and small mean size and young age at sexual maturity for males may be a direct result of intensive demersal fishing in the southern Arabian Gulf. There was an exponential increase in the cumulative reproductive potential with size and a linear increase with age for both sexes. The mean L(F) (L(c50) ) at which D. pictum became vulnerable to capture was 33·3 cm, which corresponded to only 3 and 7% of the cumulative reproductive potential of males and females, respectively. Size-specific and age-specific reproductive potential indicated that conventional regulations that equate the mean size at first capture to sexual maturation are unsuitable for the management of D. pictum.     

Reproductive biology of the smooth butterfly ray Gymnura micrura

This study provides the first detailed information on the reproductive biology of the smooth butterfly ray Gymnura micrura. A total of 905 individuals were sampled, 377 of which were used for the reproductive study. Juveniles accounted for 75% of the sample, but all life cycle stages were present in the study area. The disc width at which 50% were mature (W(D50) )was estimated at 269 and 405 mm for males and females, respectively. The W(D50V) (based on the onset of vitellogenesis) was estimated at 359 mm. Uterine fecundity (mean ±s.d. = 3·8 ± 1·3; range: 1-6) was positively correlated with female size. A 3564% gain in mean wet mass was observed from egg to full-term embryo in utero. Size at birth ranged from 135 to 175 mm W(D) (19·5 to 55·0 g), with a mean of 165·1 mm W(D) (43·3 g). The embryo sex ratio was not significantly different from 1:1. The ovaries of pregnant females were undergoing vitellogenesis during gestation, with females ready to ovulate soon after parturition. Gymnura micrura may have an asynchronous reproductive cycle, with females reproducing continuously throughout the year.     

Age and growth of the endemic Xingu River stingray Potamotrygon leopoldi validated using fluorescent dyes

Between 2003 and 2005, vertebrae of 151 Xingu River Potamotrygon leopoldi (Potamotrygonidae) (75 males and 76 females) were analysed to derive a growth curve for this species. The disc width (W _D) was significantly different between sexes, with females measuring 149–700 mm W _D and males 109–500 mm W _D. The average percentage error for vertebrae readings of the whole sample was 2·7%. The marginal increment ratio (R _MI) showed an increasing trend with the highest value in November, decreasing from December on. The majority of vertebrae displaying R _MI zero, occurred in September, but the annual periodicity of ring deposition throughout the year was not conclusive. Tetracycline (TCN) injected specimens were held in captivity for 13 months and displayed a fluorescent mark in vertebrae confirming a yearly periodicity of band pair formation with the translucent ring deposited in September–October. The Akaike information criterion (AIC) showed that, among the seven models considered, the best fit was obtained for the von Bertalanffy modified with W ₀ (where W ₀ = W _D at birth) for both sexes. Growth parameters for females were: W ₀ = 149 mm; W _∞ = 763·06 mm; k = 0·12 year^{– 1}, whereas for males: W ₀ = 109 mm; W _∞ = 536·4 and k = 0·22 year^?1. Maximal ages were 7·2 years in males and 14·3 years in females. The species shows sexual dimorphism expressed in the growth pattern, size at maturity, longevity and asymptotic sizes. Concern for sustainability is raised due to the construction of the Belo Monte Hydroelectric Power Plant (2015 and 2016) in the State of Pará causing changes to the habitat of this species, which is endemic to the Xingu River and two of its tributaries.     

Growth, size and age at maturity of the agile frog (Rana dalmatina) in an Iberian Peninsula population

The mean age of a population of agile frogs (Rana dalmatina) from the Iberian Peninsula was estimated using mark and recapture and skeletochronology. Life-history parameters, including growth rate, body length, age and size at maturity, sexual dimorphism and longevity, were studied. The regression between age and snout-vent length (SVL) was highly significant in both sexes. Males reached sexual maturity at two years of age, although sometimes they can reach it at only one year of age. The average SVL at maturity was 51.75 mm (standard error (SE) = 0.71; n = 45). Females reached sexual maturity at two years of age with an average SVL of 62.14 mm (SE = 2.20; n = 14). A subset of the female population reached sexual maturity at three years of age. Growth was rapid until sexual maturity was reached. There was an overlap of SVL between different age classes. Growth was continuous, fulfilling the conditions of Von Bertalanffy's model. The growth coefficient (K) was 0.840 in males and 0.625 in females. The maximum SVL was greater in females (73.00 mm) than in males (59.50 mm). Sexual dimorphism was significantly biased towards females in all age classes. The maximum longevity observed was 6 years in females and 8 years in males. Management strategies for agile frogs should take into account factors such as these life-history characteristics.     

Reproductive variables of Urotrygon rogersi (Batoidea: Urotrygonidae): a species with a triannual reproductive cycle in the eastern tropical Pacific Ocean

Reproductive aspects of the round ray Urotrygon rogersi were studied based on 2005 specimens obtained in the artisanal shrimp fishery operating on the Colombian Pacific coast. Females reached greater maximum total length (L(T) ), disc width (W(D) ) and mass (M) (38·0 cm, 19·9 cm and 348 g) than males (32·5 cm, 17·0 cm and 165 g). Sex ratio of juveniles and adults was 1:1. Clasper length increased rapidly between 10·0 and 12·5 cm W(D) . The smallest mature male measured 10·5 cm W(D) and the largest immature individual 13·7 cm W(D) . Male first maturity was reached at 61·8% of maximum W(D) , and estimated W(D50) was between 11·5 and 11·8 cm. The smallest mature female measured 10·5 cm W(D) ; the size at first maturity was 52·8% of maximum W(D) , and estimated W(D50) was between 11·8 and 12·3 cm. Embryos were found in females ≥ 10·5 cm W(D) and maximum fecundity was three embryos per female (mode = 1) and varied with maternal size. Embryos were found in all months, but three birthing peaks per year were identified and a gestation period of 4-5 months estimated. Based on ovulation time, embryonic growth and parturition dates, a triannual reproductive cycle was inferred for this species, with overlapping ovarian and uterine cycles. These results suggest that U. rogersi has a reproductive strategy based on low fecundity, a rapid reproductive cycle (short ovulation and gestation time), three birth peaks per year and large embryos. This strategy probably allows U. rogersi to withstand the fishing pressure they are subject to on the Colombian Pacific coast. The results also suggest that the study area is an important nursery and reproductive area for this species.     

Age and growth of albacore Thunnus alalunga in the North Pacific Ocean

The age and growth of North Pacific albacore Thunnus alalunga were investigated using obliquely sectioned sagittal otoliths from samples of 126 females and 148 males. Otolith edge analysis indicated that the identified annulus in a sagittal otolith is primarily formed during the period from September to February. The assessments of the fish age at first annulus formation indicated that the first annulus represents an age of <1 year. This study presents an age estimate (0·75 years) for the formation of the first annulus. The oldest fish ages observed in this study were 10 years for females and 14 years for males. The von Bertalanffy growth parameters of females estimated were L(∞) = 103·5 cm in fork length (L(F) ), K = 0·340 year(-1) and t(0) = -0·53 years, and the parameters of males were L(∞) = 114·0 cm, K = 0·253 year(-1) and t(0) = -1·01 years. Sexual size dimorphism between males and females seemed to occur after reaching sexual maturity. The coefficients of the power function for expressing the L(F) -mass relationship obtained from sex-pooled data were a = 2·964 × 10(-5) and b = 2·928.     

Life history characteristics of a lightly exploited stock of Squalus suckleyi

The purpose of this study was to examine the basic life history of a lightly exploited stock of Squalus suckleyi in the Gulf of Alaska to establish a baseline for future comparison and to provide critical information for stock assessments. Average total length (total length extended) of females (87·7 cm) was significantly larger (t-test, t = -12·57, d.f. = 1533, P < 0·01) than males (80·3 cm); size at 50% maturity (74·5 and 97·3 cm, males and females, respectively) and age at 50% maturity (21 and 36 years, respectively) were also significantly different between the sexes (i.e. bootstrapped 95% c.i. did not overlap). Total average fecundity was 8·5 pups per female, and individual fecundity was a linear function of either length or whole mass. The best estimate of instantaneous natural mortality was 0·097. The delayed age of maturity, low natural mortality and low rates of reproduction imply that only very low rates of fishing mortality are sustainable. Finally, this paper provides the first reported evidence that a small percentage of the adult females may undergo an extended resting period between pregnancies of ≥ 1 years.     

Production of donor-derived offspring by transfer of primordial germ cells in Japanese quail.

We transfused concentrated primordial germ cells (PGCs) of the black strain (D: homozygous for the autosomal incomplete dominant gene, D) of quail into the embryos of the wild-type plumage strain (WP: d+/d+) of quail. The recipient quail were raised until sexual maturity and a progeny test of the putative germline chimeras was performed to examine the donor gamete-derived offspring (D/d+). Thirty-one percent (36/115) of the transfused quail hatched and 21 (13 females and 8 males) of them reached maturity. Five females and 2 males were germline chimeras producing donor gamete-derived offspring. Transmission rates of the donor derived gametes in the chimeric females and males were 1.8-8.3% and 2.6-63.0%, respectively. Germline chimeric and the other putative chimeric males were also test-mated with females from the sex-linked imperfect albino strain (AL: d+/d+, al/W, where al indicates the sex-linked imperfect albino gene on the Z chromosome, and W indicates the W chromosome) for autosexing of W-bearing spermatozoa: No albino offspring were born.     

Size at the onset of sexual maturity in the anomuran crab, Aegla uruguayana (Aeglidae)

The size at maturity was studied in the crab Aegla uruguayana from the Areco River (31°14′ S, 59°28′ W), Argentina. Size at sexual maturity was determined according to three criteria: morphometric (change in the relative growth of reproductive characters), histological (first maturation of gonads) and functional (capability to mate and carry eggs). Regarding females, morphometric maturity occurred at a carapace length (CL) of 11.50 mm, considering abdomen width as a reproductive character. Gonad maturity of females could be observed at a minimum size ranging from 15 to 17 mm CL. The smallest ovigerous female observed in the field was 15.60 mm CL, although a relevant population incidence of ovigerous females (86.6%) has just been observed at values higher than 17 mm CL. As for males, the relative growth of the left chela length changed at a value of 15.40 mm CL, while morphological changes in sexual tube occurred between CL of 14 and 16 mm. Testicular maturation occurred at a CL ranging from 17 to 19 mm. The smallest size of males having spermatozoids in their vasa deferentia was 18.70 mm CL. The results obtained indicated that, in both sexes, functional maturity occurred after morphometric maturity and at a size similar to that of gonad maturity. Comparing sexes, females acquired sexual maturity (morphometric, gonad and functional maturity) at sizes statistically smaller than those of males.     

Biology of the Dragonet, Callionymus kaianus moretonensis Johnson (Pisces:Callionymidae)

A collection in excess of 1000 specimens of Callionymus kaianus moretonensis, trawled off southern Queensland, afforded an opportunity to study various aspects of the biology of this species. It inhabits muddy bottoms at depths of 101–150 m off south-east Queensland between Noosa and Cape Moreton, Moreton Island. Penaeid prawns were the predominant food during all seasons and for all size groups. A great diversity of food items were ingested, especially in the pelecypod and gastropod categories. Factors influencing feeding and vulnerability of prey organisms are discussed. Of the 907 specimens that were sexed, 422 (46.7%) were males and 485 (53.3%) were females. C. k. moretonensis has a prolonged breeding period in which each female spawns a number of times. Only a few oocytes appear to be discharged at any one time from the ovary. Practically every stage of ovarian development was found in each ovary examined regardless of time of year. Oocyte diameter averaged 0.51 mm immediately prior to spawning and numbers of ova ranged from 1285 to 22,478. C. k. moretonensis may have either a benthic larvae or a short-lived planktonic one. Length-weight relationships are represented by the regressions, log W = -1 5.24 + 3.77 log L (males) and log W = -16.77 + 4.12 log L (females). Otoliths were used for age and growth determinations. C. k. moretonensis reaches age group IV+. Growth of males slightly exceeded that of females, with the greatest difference occurring between the third and fourth years of life. No evidence of high post-breeding mortality was found in spent males.     

乌苏里江哲罗鲑的年龄结构、性比和生长

We report the current status of Taimen (Hucho taimen ) population in Wusuli River of China. The amount of catch per year was only 1 800 - 5 400 individuals ranging from 2 - 15 years old during 1998 - 2002. Of all the captured, individuals with sexual maturity were up to 30% - 70% (female maturity at 5 years old and male 6 years old). Sex ratio varied greatly among different localities. Its breeding population mainly consisted of males aged 5 - 10 years and females aged 8 - 13 years‘‘old, which spawned in May each year. Females breed once with about 4 000 - 23 000 eggs produced every 2 - 3 years, Taimen grows fast and average growth rate is about 10 cm per year prior to 10 years‘‘s old, which corresponded with von Bertelanffy‘‘s equation calculated as Lt = 246.41 [ 1 -e 0.0407(t 0.4625)] and Wt = 174 075.72 [ 1 -e ^0.0407(t-0.4622)12.9537, and the relationship between body length and weight was W 0.015018L^u2020.     

Age and growth of the round stingray Urobatis halleri at Seal Beach, California

The age and growth of the round stingray Urobatis halleri was determined using vertebral sections from animals collected at Seal Beach, California from 2002 to 2005. Annual periodicity was validated from U. halleri injected with oxytetracycline and maintained in captivity over a 2 year period ( n = 7). The coefficients estimated by the von Bertalanffy growth model were the disc width asymptote ( W _D∞) (286 mm for males and 224 mm for females) and K (0·09 year⁻¹ for males and 0·15 year⁻¹ for females). The age structure of the population consisted of mostly older, mature males and females. Age at maturity was estimated at 3·80 years for females and 3·75 years for males, and the maximum assessed age was 14 years old. Males were more numerous than females throughout the year; however, from May to September, females outnumbered males. The U. halleri age and growth coefficients were comparable to other species in the family Urolophidae. Based on the seasonality and age structure of this population, Seal Beach offers warm-water refuge for U. halleri of reproductive maturity, and the U. halleri at Seal Beach may garner some behavioural thermoregulation benefit.     

A skeletochronological study of age, growth and longevity in a population of the frog Rana ridibunda from southern Europe

Age at sexual maturity and longevity in a population of Rana ridibunda from north-eastern Greece were studied by skeletochronology performed on the phalanges. Analysis of the age structure was based on counting the lines of arrested growth (LAGs). Sexual maturity for both sexes arises during the first year or after the first hibernation. Ages ranged from 1 to 5 years (mean=2.96) among 52 males and from 1 to 5 years (mean=3.73) among 56 females. The mean snout-vent length was 69.03+/-12.6mm in males and 82.38+/-13.27 mm in females. The difference between the sexes in age and size was significant. Growth of individuals was fitted on? The von Bertalanffy model. The growth coefficient (K) was 0.57 in males and 0.54 in females, mainly due to faster male growth between metamorphosis and maturation.     

Reproductive aspects of the yellowtail snapper Ocyurus chrysurus from the southern Gulf of Mexico

In this study, sex ratio, spawning season, fork length (L(F)) at maturity (L(F50)), batch fecundity and spawning frequency were characterized for the continental population of Ocyurus chrysurus from the Campeche Bank, in the southern Gulf of Mexico. A total of 1657 specimens were collected from February 2008 to January 2009. The overall sex ratio (male:female) and sex ratios by size-class showed no significant differences from an expected 1:1 ratio. The Campeche Bank population did not conform to the reproductive seasonality pattern characteristic of a continental population. A protracted spawning season that extended from January to September with peaks occurring mainly between April and May and additionally in September was observed. The population conformed, however, to the sexual maturity pattern observed for populations and species associated with a continental margin. Fish of both sexes reached the onset of sexual maturity at a similar and small L(F) of c. 14 cm, and L(F50) (L(F) at which 50% of females and males become mature) was 21·3 and 19·4 cm. Asynchronous-type ovarian development was observed for this species and batch fecundity estimates ranged from 14,102 to 164,756 oocytes (mean ±S.D. = 43,852 ± 32,684 oocytes). The overall spawning frequency estimate was once every 8·3 days or 26 times during the 9 month spawning season.     

Evidence of sustained populations of a small reef fish on artificial structures. Does depth affect production on artificial reefs?

The length frequencies and age structures of resident Pseudanthias rubrizonatus (n = 407), a small protogynous serranid, were measured at four isolated artificial structures on the continental shelf of north-western Australia between June and August 2008, to determine whether these structures supported full (complete size and age-structured) populations of this species. The artificial structures were located in depths between 82 and 135 m, and growth rates of juveniles and adults, and body condition of adults, were compared among structures to determine the effect of depth on potential production. All life-history stages, including recently settled juveniles, females and terminal males, of P. rubrizonatus were caught, ranging in standard length (L(s)) from 16·9 to 96·5 mm. Presumed ages estimated from whole and sectioned otoliths ranged between 22 days and 5 years, and parameter ±s.e. estimates of the von Bertalanffy growth model were L(∞) = 152 ± 34 mm, k = 0·15(±0·05) and t(0) = -1·15(±0·15). Estimated annual growth rates were similar between shallow and deep artificial structures; however, otolith lengths and recent growth of juveniles differed among individual structures, irrespective of depth. The artificial structures therefore sustained full populations of P. rubrizonatus, from recently settled juveniles through to adults; however, confirmation of the maximum age attainable for the species is required from natural populations. Depth placement of artificial reefs may not affect the production of fish species with naturally wide depth ranges.     

Biology of the silky shark Carcharhinus falciformis (Carcharhinidae) in the eastern Indian Ocean, including an approach to estimating age when timing of parturition is not well defined

Biological data were recorded for 1265 silky sharks Carcharhinus falciformis collected from fish landing sites in eastern Indonesia. These represented catches taken in most calendar months by gillnetting and longlining in the eastern Indian Ocean and contained individuals ranging from embryos to fully mature adults. The growth zones in centra, which were shown to form annually, were counted in the vertebrae in a sub-sample of 200 fish for ageing purposes. The embryo lengths in the 5 months for which there were such data, and the presence of neonates in virtually all months, however, indicated that birth occurs throughout the year and thus there was no well-defined birth date for ageing individual fish. The approximate birth date of each individual was thus estimated from a combination of the total length (L(T) ) at capture and backcalculated L(T) at the formation of the birth zone and at the first and last growth zones in the vertebral centra, together with the period that had elapsed between the formation of those last two growth zones. The number of eggs or embryos in uteri ranged from two to 14, with a mean of 7·2. The estimated mean L(T) at birth of females (811 mm, range: 799-823 mm) and males (812 mm, range: 794-830 mm), derived from the backcalculations corresponding to the birth zones in the centra, were not significantly different (P > 0·05). The L(T) ranges in the catches of post-natal females (570-2592 mm) and males (553-2289 mm) taken by gillnetting were wider than those of the females (1177-2623 mm) and males (1184-2409 mm) taken by longlining. The oldest female and male were 19 and 20 years-old, respectively. The von Bertalanffy growth curves for the two sexes did not differ significantly. The growth coefficient, k, and the asymptotic length, L(T∞). were 0·066 year?1 and 2994 mm for the curve fitted to the combined data for females and males. The lengths L(T50) and ages A(50) at which C. falciformis attained maturity were 2156 mm and 15 years for females and 2076 mm and 13 years for males. The very high proportion of C. falciformis with lengths 相似文献   

Reproductive biology of brown trout, Salmo trutta macrostigma Dumeril 1858, in a tributary of the Ceyhan River which flows into the eastern Mediterranean Sea

The study describes some key elements of the reproductive biology, including spawning season, age at sexual maturity, fecundity and egg diameter of the native brown trout, Salmo trutta macrostigma, in a tributary of the Ceyhan River. A total of 197 brown trout (118 females and 79 males) were captured in 2000–2001 by electric fishing. In observations on monthly changes, the gonadosomatic index (GSI) and the monthly frequency distribution of egg diameter confirmed that spawning lasted from November to January. Some 27.7% of the females and 62.5% of the males attained sexual maturity in their second year. The smallest fork length (FL) of brown trout attaining sexual maturity was 17.4 cm for males and 17.8 cm for females. Mean fecundity in age groups II, III, IV and V were 360, 452, 693 and 1283 eggs per female, respectively. One 9‐year‐old female had a unique 3232 egg count. The mean fecundity of the sampled population was 554 eggs per fish, positively correlated with the FL (mm) (R = 0.8227 ) and body weight (R = 0.8130). The diameter of mature eggs in the spawning season ranged from 3.250 to 5.930 mm, with a 4.146 mm average. Mean egg diameter in age groups II, III, IV and V in the spawning season were 0.813, 3.799, 4.663 and 5.243 mm, respectively. Fecundity, egg weight and diameter were statistically different in all age groups.     

Age, growth, reproduction and mortality of the striped seabream, Lithognathus mormyrus (Pisces, Sparidae), off the Canary Islands (Central-east Atlantic)

Striped seabream, Lithognathus mormyrus L. (n=731) caught off the Canary Islands from January 1999 to June 2000 were studied. Fish ranged in size from 113 to 372 mm total length, weighing from 21.1 to 748.2 g total weight. Weight increased allometrically with size (b=2.9071). Fish age was 0–10-years-old. Growth was relatively slow (k=0.88 years⁻¹), with females growing at a slightly faster rate than males. The species displayed protandric hermaphroditism. Male : female ratio was unbalanced in favour of males (1 : 0.85). Males predominated in smaller sizes, females in larger sizes, and intersexual individuals were in intermediate sizes. The reproductive season extended from June to December, with a peak in spawning activity in August–September. Males reached maturity at 207 mm (2 years) and females at 246 mm (3 years). The real value of instantaneous rate of natural mortality was between 0.30 and 0.45 years⁻¹.