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1.
R. R. Licandeo† J. G. Lamilla P. G. Rubilar‡ R. M. Vega§ 《Journal of fish biology》2006,68(2):488-506
The age and growth parameters of Dipturus chilensis were estimated by counting growth rings from thin sections of vertebral centra from 400 fish (246 females and 154 males), ranging from 23 to 124 cm total length (LT), and backcalculating fish lengths at previous ages. Marginal increment analysis lent support to the hypothesis of annual deposition of band‐pairs, which formed during the winter months. The oldest female D. chilensis aged in this study was 21 years and 117 cm LT, whereas the oldest male was 18 years and 93 cm LT. A 4·7% index of average per cent error (IAPE) suggested that this is a precise method for calculating the age of D. chilensis. Observed LT were lower than backcalculated LT, which implies the influence of Lee's phenomenon. The von Bertalanffy growth equations, based on mean length‐at‐age data, were estimated as Lt = 128·3 (1 ? e?0·112 (t + 0·514)) for females and Lt = 107·8 (1 ? e?0·134 (t + 0·862)) for males where t is age (years). Growth was significantly different between sexes: females reached a larger adult size. Ages and lengths at 50% maturity were estimated at 14 years of age and 106 cm LT for females and 11 years of age and 86 cm LT for males. At c. 14 years, there was a decline in growth rates in females. The factor most likely responsible for this was sexual maturity, which caused a discontinuity in growth of female fish. These results show that this species is slow‐growing, long‐lived, relatively large and of delayed maturity, characteristics that make it vulnerable to exploitation. 相似文献
2.
Reproductive parameters of the Pacific angel shark Squatina californica (Selachii: Squatinidae)
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A. F. Romero‐Caicedo F. Galván‐Magaña A. Hernández‐Herrera M. Carrera‐Fernández 《Journal of fish biology》2016,88(4):1430-1440
Reproductive characteristics of the Pacific angel shark, Squatina californica, were evaluated from 420 specimens obtained from the artisanal fishery in La Paz Bay, Gulf of California, Mexico. Females (99 cm, 6000 g) were larger than males (95 cm, 5000 g) in terms of both total length (LT) and body mass (MT). The overall sex ratio was significantly different from the expected 1:1, suggesting sexual segregation of mature individuals in La Paz Bay. Males had developed reproductive organs and calcified claspers from 72 cm LT; the median size at maturity (LT50) was 75·6 cm. In females, only the left ovary was functional and mature ovarian follicles were present from 77 cm LT; the estimated LT50 was 77·7 cm. For the 10 gravid females sampled, uterine fecundity was between two and 10 embryos. Mature, non‐gravid females with small and large ovarian follicles appeared simultaneously with gravid females with follicles that did not exceed 1·9 cm diameter. 相似文献
3.
The slowing of growth as fish age has long been believed to be related to energy expenditure for maturation, and this rationalization has been used to explain why, across nearly all fish species, the relationship between size at first maturity (Lm) and maximum (Lmax) or asymptotic length (L∞) is relatively constant. In contrast, the Gill-Oxygen Limitation Theory (GOLT) postulates that (a) fish growth slows because as they grow, their two-dimensional ability to extract oxygen from the water diminishes relative to their three-dimensional weight gain, and (b) they can only invest energy for maturation if oxygen supply at their size at first maturity (Qm) exceeds that needed for maintenance metabolism (Q∞). It has been reported previously across dozens of marine fish species that the relationship between Qm and Q∞ is linear and, further, it can be mathematically converted to Lm vs. L∞ by raising both terms to the power of D (the gill surface factor), resulting in a slope of 1.36. If the GOLT is universal, a similar slope should exist for LmD vs. L∞D relationships for freshwater species across multiple individual populations that reside in disparate habitats, although to our knowledge this has never been evaluated. For analysis, we used existing data from previous studies conducted on 51 stream-dwelling populations of redband trout Oncorhynchus mykiss gairdneri, Yellowstone cutthroat trout O. clarkii bouvieri and mountain whitefish Prosopium williamsoni. The resulting LmD vs. L∞D slopes combining all data points (1.35) or for all species considered separately (range = 1.29–1.40) were indeed equivalent to the slope originally produced for the marine species from which the GOLT-derived relationship was first reported. We briefly discuss select papers both supporting and resisting various aspects of the GOLT, note that it could potentially explain shrinking sizes of marine fish, and call for more concerted research efforts combining laboratory and field expertise in fish growth research. 相似文献
4.
Liu Chong Andrés Flores Juan Carlos Quiroz Francisco Contreras Rodrigo Wiff 《Journal of fish biology》2019,95(4):1030-1039
Using an extensive database compiled by scientific observers aboard commercial fishing operations between 1984 and 2014, we describe the maturity and size structures of white warehou Seriolella caerulea and silver warehou Seriolella punctata from by-catch of the trawling industrial fisheries operating in the austral zone off Chile. Macroscopic maturity stages and gonadosomatic (IGS) index show mature females throughout the year and a pronounced spawning period in both austral autumn and winter seasons, with an IGS peak in July for S. punctata and August for S. caerulea. Reproductive patterns in both species show an extended spawning season (July to September) across the area between 43 and 47° S. Length–mass relationships showed significant differences between sexes in both species, where females reach a larger size. Fork length at 50% maturity was 43.5 cm for S. caerulea and 37.2 cm for S. punctata. Female catch composition is dominated by adult fish (96% for S. caerulea and 86% for S. punctata). Currently, both species are exploited with no assessment and management-decision framework. Therefore, information regarding reproductive biology and demographic traits becomes an important baseline to ensure adequate fisheries management for both species. 相似文献
5.
Life‐history strategies of the rock hind grouper Epinephelus adscensionis at Ascension Island
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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
6.
Reproductive biology of albacore Thunnus alalunga 总被引:1,自引:0,他引:1
Reproductive variables in albacore Thunnus alalunga were evaluated by gonad histology in samples of 132 males (58–118 cm fork length, LF) and 112 females (59–101 cm LF) that were collected from the western North Pacific Ocean from 2001 to 2006. In the sex ratio examination, males greatly outnumbered females in large adult fish (LF > 100 cm). Thunnus alalunga exhibited a protracted spawning period from March to September in the waters off eastern Taiwan and the Philippines, and the peak spawning activity occurred in March and April. Minimum sizes associated with the classification of mature fish were 78 and 83 cm LF for males and females, respectively. In addition, the largest LF of immature fish were 93 cm for males and 94 cm for females. The spawning frequency estimate in April was 1·7 days. Batch‐fecundity estimates of 21 females (89–99 cm LF) ranged between 0·17 and 1·66 million eggs (mean ±s.d . = 0·94 ± 0·43). The relative fecundity estimates of the 21 females ranged between 9·2 and 92·4 oocytes g?1 body mass (mean ±s.d . = 50·5 ± 22·8). The results presented in this study provide increased information regarding this species' reproductive‐related characteristics than are currently available in stock status determinations. 相似文献
7.
Alexander H. Knorrn Kim L. Wieben Heino O. Fock Henrike Andresen 《Journal of fish biology》2024,104(1):252-264
This study was the first to investigate the key reproductive traits of the electric lantern fish Electrona risso (Myctophidae, n = 918) and the bigscale fishes (Melamphaidae) Melamphaes polylepis (n = 260) and Scopelogadus mizolepis (n = 649). Specimens of these mesopelagic species were collected in March and April 2015 in the eastern Central Atlantic (0–24° N, 20–26° W). Sex ratio was not significantly different from 1:1 in E. risso and M. polylepis but significantly skewed toward female dominance in S. mizolepis. Reproductive phases were determined macroscopically and by histological analyses on selected individuals. Female length at 50% maturity (L50) was 55.1 mm standard length (LS) in E. risso, with an observed female maximum length (Lmax) of 81.2 mm LS. M. polylepis females had an L50 of 40.2 mm LS and an Lmax of 86.7 mm LS. S. mizolepis had an L50 of 46 mm LS and an Lmax of 97.9 mm LS. The three species show histological features of iteroparity, but the E. risso population appears to occur in two year-classes and experience only one spawning season per lifetime in the study region. All three species are batch-spawners. A batch fecundity of 2668 eggs was estimated from one E. risso individual, with a relative batch fecundity of 369 eggs g−1 gonad-free body mass. M. polylepis had a batch fecundity of 1027 eggs and a relative batch fecundity of 149 eggs g−1 (n = 3). S. polylepis had a batch fecundity of 1545 eggs and a relative batch fecundity of 215 eggs g−1 (n = 21). The median gonado-somatic index during the actively spawning phase of E. risso was 4.5, significantly lower than that of M. polylepis (7.5) and S. mizolepis (7.1). No regressing or regenerating phases were observed in this study. Batch-spawning in all three species is suggested to be advantageous to cope with intra-annual variability in food supply and other risks for offspring survival. With what appears to be in effect a (facultative) semelparous strategy in combination with a short life span in E. risso, interannual differences would have a great effect on population dynamics of this species. Knowledge is still lacking on temporal aspects of reproduction such as the duration of the spawning season and the frequency of spawning, as well as age and growth. 相似文献
8.
P. Oliveira F. H. V. Hazin F. Carvalho M. Rego R. Coelho A. Piercy G. Burgess 《Journal of fish biology》2010,76(7):1655-1670
From February 2005 to September 2007, a total of 490 crocodile sharks Pseudocarcharias kamoharai, caught as by‐catch in the swordfish and tuna longline fishery that operates in the tropical western Atlantic Ocean, was studied in regard to their reproductive biology. Maximum observed total lengths (LT) were 1220 and 1090 mm for females and males respectively, with a high proportion of the catch being composed of mature specimens. Sexual maturity was attained at 760–810 mm LT for males (LT50 = 800 mm) and 870–980 mm LT for females (LT50 = 916 mm). The size at birth was estimated at 415 mm LT. Temporal variation in gonad morphology and mass suggests that in this region P. kamoharai, an aplacental viviparous species with oophagy, does not show a well‐defined reproductive seasonality, with mating and parturition occurring possibly over an extended period of the year. Mean ±s.d . fecundity was estimated to be 3·9 (± 0·6) pups per reproductive cycle. 相似文献
9.
Anadromous trout Salmo trutta exhibits sexual size dimorphism (SSD); females were larger than males in populations where male mean total length (LT) at maturity was below 49 cm and females were smaller than males when mean male LT was above 49 cm, the slope of the regression of female on male LT was 0·59. In streams with mean annual discharge below 41 m3 s?1, flow added significantly to a model with SSD as the dependent variable and male mean LT at maturity as the first predictor variable. There was a slight increase in SSD with increasing latitude, which may result from an increase in male size with increasing latitude. 相似文献
10.
Anal‐fin ray morphology indicates sexual maturity in Brevimyrus niger (Teleostei,Mormyridae)
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This osteological survey of 249 specimens of Brevimyrus niger ranging in size from 44 to 137 mm standard length (LS) demonstrated that developmental changes in anal‐fin morphology can serve as a predictor of sexual maturity in this species. Anal‐fin ray bases begin to expand when fish reach c. 90 mm LS at which size and above there were roughly equal numbers of individuals observed with expanded and unmodified anal‐fin bases, reflecting a 1:1 sex ratio. 相似文献
11.
12.
Lucas G. Pensinger Nancy J. Brown-Peterson Christopher C. Green Stephen R. Midway 《Journal of fish biology》2021,99(2):308-320
Hardhead catfish Ariopsis felis are a common marine catfish in the coastal waters of the Gulf of Mexico (GOM). The low economic value of this species has depressed interest and research, and although the species is known for its extremely low fecundity and large oocytes, little else is known about this catfish species. A total of 1230 samples across all months of the year from 2016 to 2018 resulted in 681 females, and analysis of gonado-somatic index (IG) revealed 1% to be a clear cut-off indicating maturity. Females are considered capable of spawning from April to June when IG averaged 4–8%. Both atresia and post-ovulatory follicles were present in July, suggesting that spawning ends in July in the northern GOM. The 1% IG cut-off was used to designate maturity, and from that an L50 of 253 mm was estimated. Batch fecundity from 41 females estimated a mean batch size of 36 oocytes. Perhaps the most interesting finding was the presence of secondary growth stage oocytes (e.g., cortical alveoli) from July through November, well outside the spawning capable period. Furthermore, 78% of females had some early vitellogenic oocytes present during the non-spawning season, and the distribution of these relatively large (2–5 mm) oocytes did not change over time. The results here are not only important as reproductive biology information for a common and abundant species, but also present interesting and unusual patterns of non-spawning season oocyte development that is not commonly seen in Western Hemisphere subtropical fish species. 相似文献
13.
J. A. Sulikowski A. M. Cicia J. R. Kneebone L. J. Natanson P. C. W. Tsang 《Journal of fish biology》2009,75(10):2832-2838
Age and size at sexual maturity was determined for 185 male and 96 female smooth skates Malacoraja senta (ranging in size from 370 to 680 mm total length LT), collected from the western Gulf of Maine. Maturity ogives for males, based on clasper length, testis mass and the proportion of mature spermatocysts in the testes, suggest that 50% maturity occurs between 9 and 10 years and 560 mm LT. Maturity ogives for females, based on ovary mass, shell‐gland mass and maximum follicle size, suggest that 50% maturity occurs at age 9 years and 540 mm LT. 相似文献
14.
Gisleine Hoffmann Costa e Silva Matheus Oliveira Freitas Vinícius Abilhoa 《Journal of fish biology》2021,99(2):669-672
The reproductive biology of Centropomus parallelus was described from 589 individuals captured in estuarine and coastal waters in Southern Brazil. Length-frequency distribution showed the dominance of males in smaller length-classes (132–290 mm LT), whereas females were dominant in larger length-classes (>290 mm LT). Total length at maturity (L50) was 180 mm LT and corresponded to 29% of the maximum length recorded. Histological sections revealed one hermaphrodite (205 mm LT) and few immature females. Life history traits provided herein can contribute to sustainable fisheries management practices. 相似文献
15.
16.
The current study presents information on size distributions, size at recruitment to the fishery, size at maturity and patterns of reproduction for several small benthic fishes caught as by‐catch in the southern Gulf of California (Mexico) shrimp trawl fishery: sand perch Diplectrum spp., lumptail searobin Prionotus stephanophrys, bigscale goatfish Pseudupeneus grandisquamis and silver stardrum Stellifer illecebrosus. Pseudupeneus grandisquamis, P. stephanophrys and S. illecebrosus populations were all sexually dimorphic in size. Total‐length (LT)‐based analyses did not provide reliable information on survival and growth. The majority of sampled P. grandisquamis and S. illecebrosus were caught before reproductive maturity, whereas the majority of Diplectrum spp. and almost all P. stephanophrys were mature when caught. LT at 50% gear retention (LTc, mm) v. 50% maturity (LTm, mm): Diplectrum spp. 124·53 v. 131·43; P. grandisquamis 90·98 v. 135·20; S. illecebrosus 82·55 v. 137·30. LTc for P. stephanophrys was 104·73, but LTm could not be modelled for this species as almost all captured individuals were mature. Diplectrum spp., P. grandisquamis and S. illecebrosus were indeterminate spawners, whereas P. stephanophrys appeared to be a determinate spawner. Sex ratios were equal for each of the gonochoristic species. In general, the gonado‐somatic index (IG) increased with increasing LT for all except P. stephanophrys, where IG decreased with increasing LT for both males and females. Mature individuals of all taxa were found throughout the sampling period (September to March), and IG increased with sample day for all except females of P. grandisquamis. The current data suggest the potential for fishery effects on sampled populations of P. grandisquamis and S. illecebrosus. 相似文献
17.
Lubabalo Mofu Darragh J. Woodford Ryan J. Wasserman Olaf L. F. Weyl 《Journal of fish biology》2020,97(6):1600-1606
The river goby Glossogobius callidus is native to freshwater and estuarine habitats in South Africa. Individuals [21.1–144.4 mm total length (LT)] were sampled from impoundments in the Sundays River Valley, Eastern Cape, from February 2014 to March 2015. The largest female was 137.2 mm LT, and the largest male was 144.4 mm LT. Length-at-50% maturity was 75.2 ± 2.1 mm LT for males and 76.2 ± 2.0 mm LT for females. Absolute fecundity was 1028.2 ± 131.7 oocytes per fish, and relative fecundity was 50.1 ± 18.1 oocytes per gram. The spawning season extended from October to December. Fish were aged using sectioned sagittal otoliths. The growth zone periodicity was validated using edge analysis. Longevity was more than 7 years for females and more than 6 years for males. Length-at-age was similar for the two sexes and was best described using the von Bertalanffy growth model as Lt = 74.7(1 − e–1.0(t + 0.1)) mm LT for the entire population. Using the population age structure, the mortality rate was estimated at 1.3 per year. 相似文献
18.
Some observations on the biology of two rarely seen deep‐sea chimaerids,Chimaera carophila and Hydrolagus homonycteris
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Chimaera carophila (n = 45) and Hydrolagus homonycteris (n = 11), two deep‐sea chimaerids rarely caught in the waters off New Zealand, were collected from research trawl catches and commercial fishery catches around New Zealand at depths between 400 and 1300 m, between 2014 and 2016. Additional preserved specimens of both species (n = 58) from museum collections were analysed for size, sex and maturity. External assessment of male claspers and a combination of internal assessments of female gonad mass and oviducal gland width, were used to determine maturity. For both species, length at first maturity was 0·70–0·82 of their maximum observed chimaera length (LC), with females maturing at a larger size. Length at maturity for C. carophila (LC range: 28·7–103·9 cm) was estimated at 72·5 cm LC for males (n = 163) and 82·5 LC for females (n = 58). In H. homonycteris, length at maturity (length range: 78·6–99·8 cm LC) was estimated at 79·1 cm LC for males (n = 51) and 80·1 cm LC for females (n = 17). Ovarian fecundity was up to 31 for C. carophila and sperm storage was confirmed in the oviducal gland of this species. Both species preyed on benthic invertebrates. Some C. carophila and H. homonycteris inhabit depths beyond most current fisheries, but both species appear to be relatively rare and have reproductive parameters characteristic of low productivity, which may make these species vulnerable to population decline if mortality was to increase in the future. 相似文献
19.
Rasmus Hedeholm Trine Qvist Julius Nielsen Peter Grønkjær 《Journal of fish biology》2019,95(3):965-968
By examining the maturity of 283 black dogfish Centroscyllium fabricii from Greenland waters, a shift in size-at-maturity in both sexes over the past 25 years is observed. Size-at-first maturity decreased approximately 10 cm in both sexes, and L50 and L95 shifted similarly in males, but not in females. It is argued that bycatch in the Greenland halibut Reinhardtius hippoglossoides fishery has contributed to the observed shift, but also emphasised that such a distinct change could have a methodological component as well as being subject to effects of environmental change. 相似文献
20.
1. The release of total phosphorus (TP) and nitrogen (N in ammonium) was measured for the five most abundant fish species (>85% of biomass) in Mouse and Ranger Lakes, two biomanipulated, oligotrophic lakes in Ontario. 2. The specific release rate of both nutrients was significantly related to fish mass; log10 TP release rate (μg h?1) = 0.793 (±0.109) [log10 wet mass (g)] + 0.7817 (±0.145), and log10 N release rate (μg h?1) = 0.6946 (±0.079) [log10wet mass (g)] + 1.7481 (±0.108). 3. When fish nutrient release was standardized for abundance (all populations, 1993–95) and epilimnetic volume, fish were estimated to contribute 0.083 (±0.061) μg TP L?1 day?1, and 0.41 (±0.17) μg N L?1 day?1 in Mouse L., and 0.062 (±0.020) μg TP L?1 day?1 and 0.31 (±0.08) μg N L?1 day?1 in Ranger L. 4. In comparison, concurrent rates of total planktonic P regeneration were 1.02 (±0.45) μg L?1 day?1 (Mouse L.) and 0.85 (±0.19) μg L?1 day?1 (Ranger L.). Fish represented 8% of planktonic P release in Mouse L. and 7% in Ranger L. 5. Fish dry mass had mean elemental body compositions of 39.3% carbon, 10.9% nitrogen, and 4.0% phosphorus (all fish combined), with a mean molar C : N : P ratio of 27 : 6 : 1. This comprised about 55% and 23% of the total epilimnetic particulate P and N respectively. 6. Turnover times of P and N in fish were approximately 103 and 48 days respectively. In comparison, planktonic turnover times of particulate P in Mouse and Ranger Lakes were 4.3 and 4.4 days respectively. Given their high P content and low turnover rates, fish appear to be important P sinks in lakes. 相似文献