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1.
Ken Longenecker;Ross Langston;Juliaeta Mamesah;Yuliana Natan;Maureen Pattinasarany;Abdul W. Radjab;Ahmad Romdon;Fismatman Ruli;Prandito Simanjuntak;Febby L. Sinaga;Gino V. Limmon;Erik C. Franklin; 《Journal of fish biology》2024,105(4):1256-1267
A size-based, histological analysis of the reproductive life history of the blacktip grouper, Epinephelus fasciatus (Forsskål 1775), was conducted in Indonesia to evaluate the error rate associated with macroscopic reproductive analysis. Histological results indicated that E. fasciatus was protogynous with female L50 at 13.4 cm total length (LT) and a size at sexual transition of 22.0 cm LT. The weight–length relationship for the species was W = 0.011 L3.13. Overall sex ratios were significantly female biased, operational sex ratios were significantly male biased, and sex ratios of mature individuals varied predictably with length from female to male dominance as size increased. No significant relationship between length and batch fecundity was found. The population has a spawning period from February to August. Overall, 54.4% of macroscopic evaluations were incorrect compared to histological results. Of the errors, 14.8% were a failure to detect ovotestes, 12.7% were classifying non-gonadal tissue as ovary or testis, 12.2% were misclassifying sex, and 12.7% were misclassifying maturity status. However, the largest source of error (47.7%) was from misclassifying both sex and maturity status. Of these, 92.9% were macroscopically classified as immature females, but were histologically confirmed to be mature males. Compared to histological results, the only accurate macroscopic results were the absence of a sex-based difference in weight–length relationship and spawning seasonality estimated by a gonadosomatic index (February–June). The use of macroscopic methods to estimate reproductive life-history parameters for sex-changing reefes fish may introduce significant inaccuracies and misinterpretations. Of the parameters estimated by histological methods, size at maturity, size-specific sex ratios, and spawning seasonality have the greatest potential to inform local fishery management policy. 相似文献
2.
E. M. Schemmel M. K. Donovan C. Wiggins M. Anzivino A. M. Friedlander 《Journal of fish biology》2016,89(2):1271-1284
This research investigated the reproductive biology (sex ratio, hermaphroditic pattern, size and age at maturity) of Cephalopholis argus, known locally in Hawaii by its Tahitian name roi. The results suggest that C. argus exhibits monandric protogyny (female gonad differentiation with female to male sex change) with females reaching sexual maturity at 1.2 years (95% c.i .: 0.6, 1.6) and 20.0 cm total length (LT; 95% c.i .: 19.6, 21.2). The female to male sex ratio was 3.9:1. The average age and LT at sex change was 11.5 years (95% c.i .: 11.1, 12.9) and 39.9 cm (95% c.i .: 39.5, 41.2), respectively. Current information on spawning seasonality of this species is incomplete, but based on the occurrence of spawning capable and actively spawning females, spawning probably takes place from May to October. Evidence of lunar spawning periodicity was found, with an increased proportion of spawning capable and actively spawning females, and an increased female gonado‐somatic index during first quarter and full‐moon phases. This information fills a valuable information gap in Hawaii and across the species' native range. 相似文献
3.
E. T. Nolan K. J. Downes A. Richardson A. Arkhipkin P. Brickle J. Brown R. J. Mrowicki Z. Shcherbich N. Weber S. B. Weber 《Journal of fish biology》2017,91(6):1549-1568
Epinephelus adscensionis sampled from Ascension Island, South Atlantic Ocean, exhibits distinct life‐history traits, including larger maximum size and size at sexual maturity than previous studies have demonstrated for this species in other locations. Otolith analysis yielded a maximum estimated age of 25 years, with calculated von Bertalanffy growth parameters of: L∞ = 55·14, K = 0·19, t0 = ?0·88. Monthly gonad staging and analysis of gonad‐somatic index (IG) provide evidence for spawning from July to November with an IG peak in August (austral winter), during which time somatic growth is also suppressed. Observed patterns of sexual development were supportive of protogyny, although further work is needed to confirm this. Mean size at sexual maturity for females was 28·9 cm total length (LT; 95% C.I. 27·1–30·7 cm) and no females were found >12 years and 48·0 cm LT, whereas all confirmed males sampled were mature, >35·1 cm LT with an age range from 3 to 18 years. The modelled size at which 50% of individuals were male was 41·8 cm (95% C.I. 40·4–43·2 cm). As far as is known, this study represents the first comprehensive investigation into the growth and reproduction of E. adscensionis at its type locality of Ascension Island and suggests that the population may be affected less by fisheries than elsewhere in its range. Nevertheless, improved regulation of the recreational fishery and sustained monitoring of abundance, length frequencies and life‐history parameters are needed to inform long‐term management measures, which could include the creation of marine reserves, size or temporal catch limits and stricter export controls. 相似文献
4.
Life cycle and reproductive biology of the marbled goby Pomatoschistus marmoratus was studied in the Venetian Lagoon. Lifespan was determined by reading otoliths. The maximum age recorded was 17 months juveniles occurred in samples from July to November. Nests were found in two different periods: from the middle of April to the middle of July and from the middle of August to the end of September. While individuals in a wide range of body size (35–62mm total length) mated during the first spawning peak during the second one only small individuals (28–32mm total length) developed during the first peak were in reproductive activity. Histological analyses showed that most of the juveniles developed during the first spawning peak delayed sexual maturation to the following year. Ripe females appeared to be multiple spawner showing an asynchronous ovary with oocytes at different stages of development. From nesting male body sizes gonadosomatic indices and histological analyses no indication of the presence of alternative male mating tactics emerged. 相似文献
5.
Aspects of the reproductive biology of gag Mycteroperca microlepis in the southern Gulf of Mexico were studied by following seasonal variations in the gonado‐somatic index and through histological examination of gonads. Gag were collected from inshore and offshore waters of the Campeche Bank, Yucatan, Mexico, between April 1996 and December 2001. This species is a protogynous hermaphrodite, and appeared to be depth‐size distributed. The smallest gag (9–49 cm L F ) collected were all juvenile females, and were caught in inshore waters (1–10 m depth), while the largest (49–116 cm L F ), mainly adult females, males and transitionals, were captured in offshore waters (33–167 m depth). Overall the offshore male to female ratio was female‐biased (1 : 3·3) and differed significantly from unity. The species spawns at depths of c . 50–53 m, from early winter to mid‐spring, with peak spawning activity occurring between January and March. Fifty per cent of females reached first maturity at 72·1 cm L F . At 103 cm L F , 50% of sampled females had changed into males. Gag can be considered a monandric species, and sexual transition for this grouper seemed to occur in fish distributed within a narrow size range (85–111 cm L F ). The results are compared with those of other authors for gag stocks from the south‐east Atlantic coast of the U.S.A. and the north‐east Gulf of Mexico. 相似文献
6.
E. M. Grandcourt † T. Z. Al Abdessalaam † F. Francis † A. T. Al Shamsi † S. A. Hartmann † 《Journal of fish biology》2009,74(4):820-841
The reproductive biology of Epinephelus coioides was determined from the examination of 1455 individuals collected between July 2005 and June 2007 in the southern Arabian Gulf. Histological preparations of gonads indicated that males were either derived from a juvenile phase or the transition of postspawning females, confirming a diandric protogynous sexual pattern. The spawning season was well defined, occurring once a year during April and early May. Peaks in spawning occurred after the full and new moons and was completed within a single lunar cycle. The presence of mature males over the entire size and age range and the absence of inactive mature females during the spawning season suggested that the population was not constrained by sperm limitation. While specimens undergoing sexual transition were only observed in size and age ranges of 335–685 mm total length ( L T ) and 5–6 years, patterns in the proportion of males in size and age classes suggested that sex change occurred at a relatively constant rate after female maturation up to the maximum size (1002 mm L T ) and age (11 years). Relationships between reproductive output and capacity with size and age indicated that conventional regulations that equate the mean size at first capture to sexual maturation are unsuitable for the management of E. coioides . The maximum age, small size and young age at sexual maturation ( L min = 320 mm L T , 2 years, for females and 242 mm L T , 1 year, for males) conflict with the general pattern for large epinepheline groupers and may be a direct result of the intensive demersal fishery in the southern Arabian Gulf. 相似文献
7.
Northern rock sole Lepidopsetta polyxystra females from the Kodiak Island area, Alaska, reached 50% maturity at 328 mm L T and an average age of 7 years. In contrast, southern rock sole Lepidopsetta bilineata females reached 50% maturity at 347 mm L T and an average age of 9 years. Spawning started in midwinter for northern rock sole and peaked during the spring, while spawning for southern rock sole occurred during the summer. The bottom depth for spawning northern rock sole ranged from 43 to 61 m and averaged 45 m; spawning depth for southern rock sole ranged from 35 to 120m and averaged 78m. Both species appeared to develop a single stock of oocytes and to ovulate them in a single spawning. Northern rock sole females grew faster overall ( K =0.24) than southern rock sole females ( K =0.12) but reached a smaller maximum length ( L ∞ =430 mm) than southern rock sole ( L ∞ =520mm). Males of both species grew more slowly than females after 5 years of age and reached a smaller maximum length. 相似文献
8.
Otoliths and gonads of blackbelly rosefish Helicolenus dactylopterus dactylopterus were collected from the commercial fishery off the Carolinas in 1994–1997. Opaque bands on transverse sections of otoliths were determined to be annuli by analysis of marginal increments. Opaque zone formation occurs between July and January. Ages ranged from 7 to 30 years. Blackbelly rosefish have intraovarian gestation. Fertilization is internal, as free spermatozoa were found primarily in resting ovaries from July through early December with peak occurrence in September through November. There was a delay of 1–3 months before fertilization, as oocyte development did not begin until December. Occurrence during January through April of early-celled embryos, the most advanced stage observed, and postovulatory follicles indicated that oocyte development was rapid. Egg development occurs in a clear gelatinous matrix secreted into the ovarian cavity. The reproductive mode is a zygoparous form of oviparity, intermediate between oviparity and viviparity. Population sex ratio departed markedly from 1: 1 for most length intervals. Males were more abundant at lengths >250 mm L T and the overall male: female ratio was 1 : 0·60. 相似文献
9.
Grandcourt EM Al Abdessalaam TZ Francis F Al Shamsi AT 《Journal of fish biology》2010,77(10):2229-2247
The reproductive biology of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf was determined from the examination of 781 individuals collected between September 2008 and August 2009. There was no histological evidence of adult sex change, and sex ratios did not differ significantly from unity across all size and age classes. Testes had an ovarian structure and a remnant lumen which was not used for sperm transport; furthermore, residual oocytes were observed in the testes of some immature, resting and developing males. A dramatic change in the sex ratio of the smallest and youngest size and age classes suggested that juvenile female to male sex change occurred between 21·0 cm fork length (L(F)) and 24·0 cm L(F) at 1 year of age. The combination of histological evidence with the sexual composition of the size and age structures suggests a non-functional protogynous hermaphroditic sexual pattern, which is analogous to functional gonochorism. The spawning season was well defined, occurring once a year during March, April and early May. Peaks in spawning occurred after full moons, there was a cessation in spawning activity after new moons and spawning was completed within three lunar cycles. The distribution of males over the entire size and age ranges and the absence of inactive mature females during the spawning season suggested that the population was not constrained by sperm limitation. 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 L. nebulosus. The maximum recorded age (11 years), small mean size and young age at sexual maturation (L(m50) = 26·7 cm L(F), 2·1 years, for females and 19·4 cm L(F), 0·5 years, for males) may be a direct result of intensive demersal fishing in the southern Arabian Gulf. 相似文献
10.
The temporal relationship between growth history, sex-specific growth divergence and sex change was investigated in the haremic sandperch Parapercis snyderi using otolith microstructure and gonad histology. Parapercis synderi was found to display rapid near-linear growth with a maximum longevity of 303 days. All individuals matured first as female and later changed sex to become male (monandric protogynous hermaphroditism). Individual age-based growth histories obtained from otolith increment widths illustrated that males were larger than females at any given age. Males were found to diverge from the female growth trajectory during two ontogenetic periods; during the larval period and during the period that sex change took place. In addition, male otoliths contained a discontinuity, or 'check mark', associated with the rapid increase in otolith growth during the sex-change period. This microstructural feature was absent from all female otoliths. Accelerated growth in male otoliths lasted up to 25 days, following check-mark formation, after which time otolith growth returned to the pre-check-mark rate. Given the isometric relationship between otolith and somatic growth in P. synderi , and the temporal relationship between the time of check-mark formation and gonad condition, these results strongly suggest that individuals accelerate somatic growth during sex change to become the largest members of the population. Moreover, evidence suggests that the factors that determine the initial growth of larvae influence which individuals will later become males and achieve the highest reproductive success. 相似文献
11.
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. 相似文献
12.
The reproductive biology of female bigeye tuna Thunnus obesus was assessed by examining 888 fish (ranging from 84·9 to 174·4 cm fork length, LF) caught by Taiwanese offshore longliners in the western Pacific Ocean from November 1997 to November 1998 and November to December 1999 and 258 gonad samples from these fish. The overall sex ratio of the catch during the sampling differed significantly from 0·5, but males were predominant in sizes >140 cm LF. Reproductive activity (assessed by histology), a gonado‐somatic index, and the size‐frequency distributions of whole oocytes indicated that spawning occurred throughout the year and the major spawning season appeared to be from February to September. The estimated sizes at 50% maturity (LF50) of females was 102·85 cm (95% c.i .: 90·79–110·21 cm) and the smallest mature female was 99·7 cm LF. They are multiple spawners and oocytes develop asynchronously. The proportion of mature (0·63) and reproductively active (0·70) females with ovaries containing postovulatory follicles indicated that they spawn almost daily. Batch fecundity for 15 females with the most advanced oocytes (>730 µm) ranged from 0·84 to 8·56 million eggs (mean ± s.d . = 3·06 ± 2·09). The relationships between batch fecundity (FB, in millions of eggs) and LF (cm) and round mass (MR, kg) were (r2 = 0·84) and (r2 = 0·80), respectively. The parameters estimated in this study are key information for stock assessments of T. obesus in the western Pacific Ocean and will contribute to the conservation and sustainable yield of this species. 相似文献
13.
Margarita Kovalyova 《Molluscan research.》2017,37(3):159-166
For the first time, aspects of the reproduction of the little-known rock-borer mollusc Petricola lithophaga (Retzius, 1788) are described. Specimens were studied during the period from June 2012 to June 2014 (Black Sea, Sevastopol Bay). Histological methods were used to describe gametogenesis stages and spawning of the molluscs. The size and age of onset of sexual maturity, individual fecundity and other factors are defined. 相似文献
14.
磷虾是南大洋生态系统的基本组成部分,它们在南极海洋食物网中扮演着关键角色。磷虾可能是人类未开发的最大动物蛋白质来源,人类对磷虾资源开发的兴趣日趋增加,但目前关于这些种类的基础生物学,尤其是除南极大磷虾以外的其他磷虾类繁殖特性的了解极为匮乏。本文对已有相关研究进行梳理,揭示了不同种磷虾卵巢发育经历相似的生理步骤;磷虾卵母细胞大小存在区域性差异;通过观察第二性征和卵巢形态可以划分雌性磷虾的发育阶段;磷虾种间产卵期具有纬度差异,种内具有区域差异;多数调查发现样本中雌性磷虾个体占优。在此基础上,本文对今后的研究重点提出展望:1)加强南极大磷虾之外磷虾生殖特性的研究,探索磷虾生殖特点的季节性、区域性对磷虾环南极分布的影响;2)重点关注实验生物学研究,厘清磷虾的产卵次数及机制,以期准确估算繁殖力以评估磷虾资源开发可能产生的影响。 相似文献
15.
This study provides direct and indirect evidence of temporally and spatially consistent spawning aggregations for the grouper Mycteroperca olfax. Recently reported declines in population numbers, probably related to the direct targeting of aggregations by artisanal fishermen, highlight the urgent need for species‐specific management actions in the Galapagos Marine Reserve, such as minimum and maximum landing sizes, and the importance of protecting key aggregation sites with the declaration of no‐take areas and the establishment of total fishing bans during the reproductive season. 相似文献
16.
T. Brulé 《Journal of fish biology》2015,86(1):162-185
Spawning aggregations of red hind Epinephelus guttatus, tiger grouper Mycteroperca tigris and yellowfin grouper Mycteroperca venenosa were identified at two coral‐reef systems: Arrecife Alacranes (emergent bank reef) and Bajos del Norte (submerged bank reef) on the continental shelf of the Yucatan Peninsula (Campeche Bank), Mexico. At both reefs, E. guttatus forms large spawning aggregations between February and March. At Bajos del Norte, M. tigris reproduces in a small, low‐density aggregation in May, while M. venenosa aggregates at high densities for spawning between March and May. Multi‐species use of an aggregation site by E. guttatus and M. venenosa was observed at Bajos del Norte. The identified spawning aggregations are apparently stable in location over time, and all three species were commonly observed to spawn within 1 week following the full moon. Development and survival of the larvae spawned in these aggregations are probably aided by a seasonal (spring–summer) upwelling in the north‐east Campeche Bank. A permanent area closure at Bajos del Norte, currently outside any specific fisheries management area or regulations, would provide protection needed for the spawning aggregations of these three species. 相似文献
17.
T. Morato P. Afonso N. Carvalho P. Lourinho R. S. Santos H. M. Krug R. D. M. Nash 《Marine Biology Research》2007,3(6):403-411
The wide-eyed flounder, Bothus podas, occurs in many East Atlantic sub-tropical and temperate inshore areas and is the dominant flatfish in shallow-water areas around the Azores. The aim of this study was to examine the growth, reproductive biology and recruitment patterns of the wide-eyed flounder in the Azores. Adult fish samples were obtained by spear fishing and SCUBA hand netting at Faial Island. Juveniles were obtained from a complementary monthly beach-seining programme undertaken at Porto Pim Bay, Faial. Sex and development stage were determined by macroscopic examination of gonads, whereas age estimates were obtained by counting the number of opaque bands in the otoliths. In the Azores, B. podas reaches 6 years old, which is more than reported for the central Mediterranean, the only other population of this species that has been studied. The studied population has a sex ratio biased to males, which contrasts to a previous observational study, which noted a female-biased sex ratio. Spawning time, as determined from the gonadosomatic ratio and the macroscopic examination of gonads, was between July and September. This time period agrees with behavioural observations in the same area. Sexual maturity was estimated at a total length (TL50) of 14.1 cm and at an age (A50) of 1.7 years. Small juveniles occur on sandy inshore nursery areas for most of the year, but mainly between July and August each year. The presence of small fish throughout most of the year could suggest a protracted settlement period or slow growth on occasions on the shallow-water nursery grounds. 相似文献
18.
T. Morato† P. Afonso P. Lourinho R. D. M. Nash‡ R. S. Santos 《Journal of fish biology》2003,63(1):59-72
The life history of the white sea bream Diplodus sargus in the Azores showed a pattern consistent with digynic hermaphroditism achieving sexual maturity during the second year of life, at 16·7 cm L T . Spawning occurred from March to June at temperatures between 15 and 17° C and the onset and duration of spawning season in the sea bream appeared to be influenced by sea water temperatures. As latitude decreased, both in the northern and southern hemispheres, the spawning season of D. sargus populations started earlier and extended longer, highlighting the potential importance of temperature to the onset and duration of reproduction in this species. Settlement took place from late May to July, and settlers remained in the nursery area for c . 2·5 months. Emigration from the nursery area to join shoals of juveniles occurred from late July to September. 相似文献
19.
In haremic angelfishes where protogynous (female to male) sexchange is favored, females have been reported to adopt severaltactics for earlier sex change on the basis of a trade-offbetween reproduction and growth, or survivorship. A recentfield study on Centropyge ferrugatus revealed that femalesreduce spawning frequency in competition with similar-sized
neighbors for social dominance. To evaluate the optimal spawningstrategy taken by haremic fishes, we developed an evolutionarilystable strategy model that focuses on their life history andsocial structure based on field data of C. ferrugatus. Theresults of the analysis predict that the spawning frequencywill be low when the mortality rate of females is high comparedwith males, the harem size is large, and there is a moderatedegree of social control. Our model further predicts conditionsunder which females completely stop spawning, as if they havebecome bachelors. Thus, the regulated spawning frequency maybe taken as a strategy to optimize the reproductive successof an individual in response to the available choices for sexchange, social control, and environmental conditions. Socialcontrol would also play an important role in sex change inmany other haremic species. 相似文献
20.
Length and mass data for 1260 (536 females, 683 males, 41 sex unknown) striped marlin Kajikia audax were collected at the fish markets of Tungkang, Singkang and Nanfangao from July 2004 to September 2010. Of these samples, 534 gonads (236 females and 298 males) ranging from 95 to 206 cm in eye‐to‐fork length (L EF ) and 8 to 88 kg in round mass (M R), were collected. Chi‐square tests indicated sex ratios were homogeneous among months in 2004 and 2006–2008, but not in 2005, 2009 and 2010; and there were significant differences in sex ratio by size. The overall sex ratio (R S ) differed significantly from the expected 0·5. Kajikia audax are sexually dimorphic and the proportions of females increased with size between 140 and 210 cm L EF . Reproductive activity was assessed using a gonado‐somatic index (I G ), external appearance of the gonads and histological examination and results indicated that the spawning season occurred from April to August with a peak in June to July. Based on histological observations and the distribution of oocyte diameters, K. audax are multiple spawners and their oocytes develop asynchronously. The estimated length‐at‐50% maturity (L EF50 ) was c . 181 cm (c . 4·8 years of age) for females. The proportion of reproductively active females in the spawning season with ovaries containing postovulatory follicles (0·27) indicated that they spawned every 3·7 days on average. The hydrated oocyte method estimated mean ± S.D. batch fecundity (F B ) to be 4·4 ± 2·02 million eggs; average relative fecundity was 53·6 ± 13·9 oocytes g?1 M R; and the average annual fecundity was 181·3 ± 48·3 million eggs. The parameters estimated in this study are key information for stock assessments of K. audax in the north‐western and central Pacific and will contribute to the conservation, management and sustainable yield of this species. 相似文献