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Fishes, Volume 4, Issue 3 (September 2019) – 13 articles

Cover Story (view full-size image): Beginning in 2002, New Zealand’s National Institute of Water and Atmospheric Research (NIWA) established a breeding program for the wreckfish (Polyprion oxygeneios), locally known as ‘hāpuku’. Wild-caught hāpuku spawn readily in captivity, but although first filial (F1) hāpuku complete vitellogenesis, females fail to undergo oocyte maturation and spawn or produce poor-quality eggs. We examined whether administration of a synthetic agonist of gonadotropin-releasing hormone (GnRHa) could improve F1 hāpuku spawning in captivity. This study successfully achieved two key aims: induction of spawning with GnRHa and closing of the life-cycle of hāpuku by producing second generation offspring. View this paper.
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16 pages, 2509 KiB  
Article
In Vitro Effects of Bisphenol A and Tetrabromobisphenol A on Cell Viability and Reproduction-Related Gene Expression in Pituitaries from Sexually Maturing Atlantic Cod (Gadus morhua L.)
by Kristine von Krogh, Erik Ropstad, Rasoul Nourizadeh-Lillabadi, Trude Marie Haug and Finn-Arne Weltzien
Fishes 2019, 4(3), 48; https://doi.org/10.3390/fishes4030048 - 17 Sep 2019
Cited by 12 | Viewed by 4609
Abstract
Bisphenol A (BPA) and tetrabromobisphenol A (TBBPA) are widely used industrial chemicals, ubiquitously present in the environment. While BPA is a well-known endocrine disruptor and able to affect all levels of the teleost reproductive axis, information regarding TBBPA on this subject is very [...] Read more.
Bisphenol A (BPA) and tetrabromobisphenol A (TBBPA) are widely used industrial chemicals, ubiquitously present in the environment. While BPA is a well-known endocrine disruptor and able to affect all levels of the teleost reproductive axis, information regarding TBBPA on this subject is very limited. Using primary cultures from Atlantic cod (Gadus morhua), the present study was aimed at investigating potential direct effects of acute (72 h) BPA and TBBPA exposure on cell viability and the expression of reproductive-relevant genes in the pituitary. The results revealed that both bisphenols stimulate cell viability in terms of metabolic activity and membrane integrity at environmentally relevant concentrations. BPA had no direct effects on gonadotropin gene expression, but enhanced the expression of gonadotropin-releasing hormone (GnRH) receptor 2a, the main gonadotropin modulator in Atlantic cod. In contrast, TBBPA increased gonadotropin transcript levels but had no effect on GnRH receptor mRNA. In conclusion, both anthropogenic compounds display endocrine disruptive properties and are able to directly interfere with gene expression related to reproductive function in cod pituitary cells at environmentally relevant concentrations in vitro. Full article
(This article belongs to the Special Issue Fish as Model Organisms for (Eco)Toxicology and Disease)
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17 pages, 356 KiB  
Article
Performance of Marine Lecithin Supplemented Feeds for the Common Octopus (Octopus vulgaris) Ongrowing: Changes in Proximate Composition and Lipid Classes’ Profile
by Tania Rodríguez-González, Jesús Cerezo Valverde and Benjamín García García
Fishes 2019, 4(3), 47; https://doi.org/10.3390/fishes4030047 - 12 Sep 2019
Viewed by 2899
Abstract
The development of artificial diets is considered vital for feasible cephalopods’ culture. Octopus vulgaris need a diet with a high protein content but also lipids are important at a lower quantity, as polar lipids and LC-PUFA are essential for development during early stages. [...] Read more.
The development of artificial diets is considered vital for feasible cephalopods’ culture. Octopus vulgaris need a diet with a high protein content but also lipids are important at a lower quantity, as polar lipids and LC-PUFA are essential for development during early stages. In the present study the suitability of marine lecithin as a dietary supplement for O. vulgaris juveniles’ formulated feeds was tested for 56 days, assessing the performance, changes in proximate composition, and lipid classes’ profile in the digestive gland and carcass. Sixteen octopus were fed one of two semi-moist feeds based on dry ingredients: either CALPRO (N = 4) as control or CALPRO-LM (N = 8); which differed from the first, due to the inclusion of 20 g/kg of marine lecithin as a phospholipid dietary supplement. Results showed that marine lecithin did not enhance feed intake, growth, protein or lipid incorporation, nutrients digestibility or feed efficiency. Moreover, at this level of inclusion, the composition of tissues (digestive gland and carcass) regarding macronutrients and lipid classes’ profile presented only a small amount of differences. In conclusion, the inclusion of marine lecithin did not promote beneficial effects on performance, making necessary further research related to the nutritional requirements of common octopus. Full article
23 pages, 2704 KiB  
Article
1H NMR-Based Metabolomics and Lipid Analyses Revealed the Effect of Dietary Replacement of Microbial Extracts or Mussel Meal with Fish Meal to Arctic Charr (Salvelinus alpinus)
by Liane Wagner, Pedro Gómez-Requeni, Ali A. Moazzami, Torbjörn Lundh, Aleksandar Vidakovic, Markus Langeland, Anders Kiessling and Jana Pickova
Fishes 2019, 4(3), 46; https://doi.org/10.3390/fishes4030046 - 10 Sep 2019
Cited by 18 | Viewed by 5561
Abstract
The effects of replacing 40% of dietary fish meal (FM) in a reference diet (REF) with either mussel meal (MM), zygomycete fungi (ZYG), extracted baker’s yeast (EY), or non-extracted baker’s yeast (NY) on the lipid and metabolic profile of Arctic charr (Salvelinus [...] Read more.
The effects of replacing 40% of dietary fish meal (FM) in a reference diet (REF) with either mussel meal (MM), zygomycete fungi (ZYG), extracted baker’s yeast (EY), or non-extracted baker’s yeast (NY) on the lipid and metabolic profile of Arctic charr (Salvelinus alpinus) were investigated. After a 14-week feeding trial, liver and muscle tissues were collected for lipid (lipid content, lipid class, fatty acid composition) and 1H NMR-based metabolomics analyses (aqueous and chloroform phases). Lipid analyses showed that fish fed ZYG diet had lower liver lipid content and thereby 10% higher level of docosahexaenoic acid compared with REF. Metabolomics analyses showed that on the one hand fish fed NY diet affected liver metabolites (2–3 fold higher concentrations of e.g., n,n-dimethylglycine and betaine) compared with REF, while, on the other hand, the muscle metabolic fingerprint was mainly affected by EY. In general, affected metabolites (e.g., alanine, anserine, betaine, hydroxyproline, isoleucine, malonate, n,n-dimethylglycine, proline, succinate, and valine) in fish fed test diets suggested that the test meal ingredients caused mainly a response in muscle metabolism. Fish metabolism was least affected by MM, which suggests that it may be suitable to replace fish meal in Arctic charr diets. Full article
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11 pages, 1981 KiB  
Conference Report
Performance of a Pool and Weir Fishway for Iberian Cyprinids Migration: A Case Study
by Anna Pedescoll, Rafael Aguado, Carlos Marcos and Gustavo González
Fishes 2019, 4(3), 45; https://doi.org/10.3390/fishes4030045 - 16 Aug 2019
Cited by 10 | Viewed by 3344
Abstract
One of the movement barriers that fish populations must overcome for migration success in the upper basin of Tormes river (Salamanca, Spain) is a 20 m high dam. The design of its pool and weir fishway for potamodromous fishes (mostly Iberian barbel—Luciobarbus [...] Read more.
One of the movement barriers that fish populations must overcome for migration success in the upper basin of Tormes river (Salamanca, Spain) is a 20 m high dam. The design of its pool and weir fishway for potamodromous fishes (mostly Iberian barbel—Luciobarbus bocagei—and Northern straight-mouth nase—Pseudochondrostoma duriense) to overcome the obstacle was improved in 2013. The aim of this study was to assess the efficiency of the fishway using FDX passive integrated transponder (PIT)-Tags inserted into the fish and PIT-Tag detection antennas at the fishway. During several sampling events, 7113 barbel and nase individuals were tagged and released at the point of capture along the basin (2538 and 4575 of which were tagged downstream and upstream, respectively). PIT-Tag Detection Antennas close to the top and bottom of the fishway monitored tagged fish continuously for 10 months (from March to December 2017), to analyze the performance of the fishway. Upstream passage efficiency was greater for barbel (60% and 25% for barbel and nase, respectively). Differences in passage efficiency between species may be due to differences in their size. Mean length for barbels attempting to pass was 336 mm (±47 mm) while for nases was 143 mm (±26 mm). Moreover, both the number of attempts to pass and ascend time for nases were higher than for barbels. Entrance efficiency was low (3.5% and 10.8% for barbel and nase, respectively), although 2017 was a very dry year, thus these results are most likely influenced by flow rates. Therefore, the fishway has proved to be functional but is actually poor for efficiency purposes, especially for small fish. Full article
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13 pages, 2792 KiB  
Article
Preliminary Estimates of Age, Growth and Natural Mortality of Margate, Haemulon album, and Black Margate, Anisotremus surinamensis, from the Southeastern United States
by Michael L. Burton, Jennifer C. Potts and Andrew D. Ostrowski
Fishes 2019, 4(3), 44; https://doi.org/10.3390/fishes4030044 - 15 Aug 2019
Cited by 2 | Viewed by 3120
Abstract
Ages of margate, Haemulon album (n = 415) and black margate, Anisotremus surinamensis (n = 130) were determined using sectioned sagittal otoliths collected from the Southeastern United States Atlantic coast from 1979 to 2017. Opaque zones were annular, forming between January and [...] Read more.
Ages of margate, Haemulon album (n = 415) and black margate, Anisotremus surinamensis (n = 130) were determined using sectioned sagittal otoliths collected from the Southeastern United States Atlantic coast from 1979 to 2017. Opaque zones were annular, forming between January and June for both species, with peaks in occurrence of otoliths with opaque margins in April for margate and March for black margate. The observed ages for margate were 0–22 years, and the largest fish measured 807 mm TL (total length). Black margate ranged in age from 3 to 17 years, and the largest fish was 641 mm TL. Weight–length relationships were: margate, ln(W) = 2.88 ln(TL) − 10.44 (n = 1327, r2 = 0.97, MSE = 0.02), where W is total weight (grams, g); black margate, ln(W) = 3.02 ln(TL) − 11.10 (n = 451, r2 = 0.95, MSE = 0.01). Von Bertalanffy growth equations were Lt = 731 (1 − e−0.23(t+0.38)) for margate, and Lt = 544 (1 − e−0.13(t+2.61)) for black margate. After re-estimating black margate growth using a bias-correction procedure to account for the lack of younger fish, growth was described by the equation Lt = 523 (1 − e−0.18(t+0.0001)). Age-invariant estimates of natural mortality were M = 0.19 y−1 and M = 0.23 y−1 for margate and black margate, respectively, while age-varying estimates of M ranged from 2.93 −0.23 y−1 for fish aged 0–22 for margate and 7.20 − 0.19 y−1 for fish aged 0–18 for black margate. This study presents the first documentation of life-history parameters for margate from the Atlantic waters off the Southeastern United States, and the first published estimate of black margate life history parameters from any geographic region. Full article
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19 pages, 1454 KiB  
Article
From Transient to Sedentary? Changes in the Home Range Size and Environmental Patterns of Movements of European Eels (Anguilla anguilla) in a Mediterranean River
by Mercedes Herrera, Raquel Moreno-Valcárcel, Ramón De Miguel Rubio and Carlos Fernández-Delgado
Fishes 2019, 4(3), 43; https://doi.org/10.3390/fishes4030043 - 13 Aug 2019
Cited by 5 | Viewed by 2975
Abstract
The habitat use of eels during the development of sedentary behavior, which depends on the animals’ body size, is unknown. Our objective was to analyze, for two years, the changes in the home range of a population of European eel (Anguilla anguilla [...] Read more.
The habitat use of eels during the development of sedentary behavior, which depends on the animals’ body size, is unknown. Our objective was to analyze, for two years, the changes in the home range of a population of European eel (Anguilla anguilla, Linnaeus, 1758) in Southern Europe in relation to the animals’ body length (TL), and the influence of environmental factors (water temperature and flow) on the local movements of this population through observation of their sedentary behavior. We used a previously-validated mark–recapture methodology, obtaining a low deviation in the estimation of the extension of the eels’ movements. Our results revealed relatively short movements in relation to other populations, and we hypothesize that this could be related to the high habitat diversity and low eel population density in the study area. The home range size showed a high variability and dispersion among the smallest eels, however, as TL increased, the variability of home range size decreased, and home ranges were larger. These changes could be associated with the acquisition of a sedentary lifestyle. Once eels had become sedentary, an environmental pattern was observed between their movements and the water temperature and flow, with larger movements observed as the flow increased and water temperature decreased. This suggests that the temporal and spatial scales of observation are of crucial importance for monitoring eel populations and for the study of population size structure, population dynamics, and biology, which can be used to improve conservation strategies. Full article
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13 pages, 1525 KiB  
Article
Modulation of the Expression of Immune-related Gene in Atlantic and Coho Salmon during Infestation with the Sea lice Caligus rogercresseyi
by Juan Pablo Pontigo, Julia Saravia, Ricardo Oyarzún, Margarita P. González, Christopher Hawes, Francisco J. Morera, Jorge Pino, Simon Wadsworth, Jose Luis P. Muñoz and Luis Vargas-Chacoff
Fishes 2019, 4(3), 42; https://doi.org/10.3390/fishes4030042 - 25 Jul 2019
Cited by 5 | Viewed by 3420
Abstract
Caligus rogercresseyi, a marine ectoparasite, causes notable economic losses for the Chilean salmonid industry. Nevertheless, the immunological responses of infected fish remain poorly understood, including proinflammatory cytokine generation and the respective modulatory effects of various cytokine receptors. This study evaluated mRNA expression [...] Read more.
Caligus rogercresseyi, a marine ectoparasite, causes notable economic losses for the Chilean salmonid industry. Nevertheless, the immunological responses of infected fish remain poorly understood, including proinflammatory cytokine generation and the respective modulatory effects of various cytokine receptors. This study evaluated mRNA expression of the NLRC5, major histocompatibility complex (MHC) class II, I-kappa-B-alpha, a regulatory that inhibits NF-kappa-B, and proinflammatory cytokines (IL-1β and IL-18) in the liver and muscle of Atlantic salmon (Salmo salar) and Coho salmon (Oncorhynchus kisutch) during a time-course C. rogercresseyi infestation trial. All assessed mRNA were strongly regulated during infestation, but S. salar showed up-regulated expression, possibly accounting for the high infestation vulnerability of this salmonid. In conclusion, this work helps to understand the modulation of the expression of different transcripts involved over short periods of C. rogercresseyi infestation in two salmonid species (S. salar and O. kisutch). Full article
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16 pages, 2079 KiB  
Article
Induced Spawning of F1 Wreckfish (Hāpuku) Polyprion oxygeneios Using a Synthetic Agonist of Gonadotropin-Releasing Hormone
by Matthew J. Wylie, Alvin N. Setiawan, Glen W. Irvine, Abigail Elizur, Yonathan Zohar, Jane E. Symonds and P. Mark Lokman
Fishes 2019, 4(3), 41; https://doi.org/10.3390/fishes4030041 - 8 Jul 2019
Cited by 2 | Viewed by 5828
Abstract
Wild-caught hāpuku (Polyprion oxygeneios) spawn readily in captivity, but although first filial (F1) hāpuku complete vitellogenesis, females fail to undergo oocyte maturation and spawn or produce poor quality eggs. This study investigated whether administration of a synthetic agonist of gonadotropin-releasing hormone [...] Read more.
Wild-caught hāpuku (Polyprion oxygeneios) spawn readily in captivity, but although first filial (F1) hāpuku complete vitellogenesis, females fail to undergo oocyte maturation and spawn or produce poor quality eggs. This study investigated whether administration of a synthetic agonist of gonadotropin-releasing hormone (GnRHa) could improve F1 hāpuku spawning and complete the life-cycle in captivity. Spawning trials were conducted over 2 years in 2013 and 2014, when F1 were aged five and six years. In 2013, females previously conditioned under a variable or constant temperature regime were implanted with GnRHa (100 μg/kg−1) or blank implants constructed of powdered cellulose and cholesterol. Spawning was erratic and egg quality very poor in all tanks. No F2 offspring were produced by communal spawning. In contrast, viable F2 larvae were produced by strip-spawning and in vitro fertilization after a series of GnRHa injections. In 2014, two additional trials were conducted: females received ethylene-vinyl acetate copolymer (EVAc) matrix implants containing GnRHa (100 μg/kg−1) or blank implants and in the second trial, two GnRHa doses (100 μg/kg−1 and 50 μg/kg−1) were tested. Eggs were first detected in all tanks 12–17 days post-implantation when females received 100 µg/kg−1 GnRHa implants, but not in the lower dose or control tanks. In summary, this study achieved induction of female spawning with GnRHa implants (target dose 100 μg/kg−1) and the successful production of F2 hāpuku in captivity by strip-spawning. Full article
(This article belongs to the Special Issue Fish Reproductive Physiology and Aquaculture)
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6 pages, 2231 KiB  
Brief Report
Standing Out in a Big Crowd: High Cultural and Economic Value of Naso unicornis in the Insular Pacific
by Brett M. Taylor
Fishes 2019, 4(3), 40; https://doi.org/10.3390/fishes4030040 - 3 Jul 2019
Cited by 7 | Viewed by 4541
Abstract
Hundreds of fish species are harvested in coral-reef fisheries in the Indo-Pacific region using a variety of fishing gears. This diversity makes the economics, ecology, and management of reef-associated fisheries inherently complex. However, across insular fisheries spanning the tropical Pacific, one species consistently [...] Read more.
Hundreds of fish species are harvested in coral-reef fisheries in the Indo-Pacific region using a variety of fishing gears. This diversity makes the economics, ecology, and management of reef-associated fisheries inherently complex. However, across insular fisheries spanning the tropical Pacific, one species consistently dominates contemporary fisheries catch: the bluespine unicornfish (Naso unicornis, Acanthuridae). I evaluated the relative contribution of N. unicornis to commercial fisheries in the insular Pacific region from long-term (>1 year) fishery surveys across various jurisdictions and provide evidence of the contemporary cultural value of this species. Overall, evidence suggests that N. unicornis is the most commercially-valuable reef-associated fish species across the insular Pacific. This notion, coupled with a diverse representation of N. unicornis across Pacific cultures, suggests that the species is presently underappreciated in its role in coastal fisheries across Pacific Island nations. Full article
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3 pages, 182 KiB  
Editorial
Welfare of Fish—No Longer the Elephant in the Room
by João L. Saraiva and Pablo Arechavala-Lopez
Fishes 2019, 4(3), 39; https://doi.org/10.3390/fishes4030039 - 3 Jul 2019
Cited by 25 | Viewed by 6440
Abstract
The concept of fish welfare is fairly recent and was overlooked for many years, based on a popular misconception that fish were “stupid” creatures devoid of any kind of sentience or mental capability [...] Full article
(This article belongs to the Special Issue Welfare of Cultured and Experimental Fishes)
16 pages, 921 KiB  
Article
Housefly (Musca domestica) Larvae Preparations after Removing the Hydrophobic Fraction Are Effective Alternatives to Fish Meal in Aquaculture Feed for Red Seabream (Pagrus major)
by Atsushi Hashizume, Atsushi Ido, Takashi Ohta, Serigne Thierno Thiaw, Ryusaku Morita, Munenori Nishikawa, Takayuki Takahashi, Chiemi Miura and Takeshi Miura
Fishes 2019, 4(3), 38; https://doi.org/10.3390/fishes4030038 - 27 Jun 2019
Cited by 25 | Viewed by 6405
Abstract
Insects are an attractive alternative to fish meal (FM) as a sustainable protein source in aquaculture feed that does not negatively impact the marine ecosystem. Despite housefly (Musca domestica) larvae having adequacy of amino acid profiles, they have sometimes been reported [...] Read more.
Insects are an attractive alternative to fish meal (FM) as a sustainable protein source in aquaculture feed that does not negatively impact the marine ecosystem. Despite housefly (Musca domestica) larvae having adequacy of amino acid profiles, they have sometimes been reported to be inferior to FM, especially for marine carnivorous fish species. Here, we report that the removal of the hydrophobic fractions from housefly larvae enables significant replacement of FM in the diet of the red seabream (Pagrus major). In a feeding trial, housefly (HF) larvae that had the hydrophobic fraction removed as a complete substitution for 70% FM produced satisfactory growth. However, HF larvae that were supplemented with the hydrophobic fraction resulted in significant growth reduction. Growth recovery was incomplete by supplementation of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) to undefatted HF larvae, being equivalent to that of fatty acid content with a control diet. Moreover, fish with a dietary intake of catechol identified from the hydrophobic fraction of the HF showed growth reduction and morphological alterations in the intestine. Our findings indicate that the hydrophobic fraction from HF larvae contains a negative factor for fish growth and eliminating the fraction from HF larvae is thought to be an important process for sustainable aquaculture. Full article
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14 pages, 805 KiB  
Article
The Dietary Lipid Content Affects the Tissue Gene Expression of Muscle Growth Biomarkers and the GH/IGF System of Pejerrey (Odontesthes bonariensis) Juveniles
by Pedro Gómez-Requeni, Mauricio Nestor Kraemer and Luis Fabián Canosa
Fishes 2019, 4(3), 37; https://doi.org/10.3390/fishes4030037 - 27 Jun 2019
Cited by 6 | Viewed by 3670
Abstract
Gene expression of growth hormone receptors (GHRs), insulin-like growth factors (IGFs), myostatin (MSTN) and myogenin (MyoG) was analyzed in juveniles pejerrey fed with graded levels of lipids (L): 6% (L6), 10% (L10), 25% (L25). After 14 weeks, no changes were found in liver [...] Read more.
Gene expression of growth hormone receptors (GHRs), insulin-like growth factors (IGFs), myostatin (MSTN) and myogenin (MyoG) was analyzed in juveniles pejerrey fed with graded levels of lipids (L): 6% (L6), 10% (L10), 25% (L25). After 14 weeks, no changes were found in liver GHR-I GHR-II and IGF-II mRNA levels whereas IGF-I decreased in L10 and L25. Muscle GHR-I gene expression increased in L25 whereas GHR-II, IGF-II and MyoG were higher in L6. IGF-I and MSTN expression was not affected by the different diets. Adipose IGF-I mRNA levels decreased in L10. Correlations between body weight and members of GH/IGF system in liver and skeletal muscle were found only in L10 group. Correlations found in L10 group between both liver and skeletal muscle GHR-I and IGF-I were lost in either L6 or L25 groups. Thus, fish fed with apparently unbalanced dietary lipid contents (6% and 25%) exhibit a compensatory regulation of systemic and local components of the GH/IGF axis. Furthermore, the marked inhibition of muscle MyoG gene expression in L25 might limit excessive lipid deposition and fish growth. Our data suggest that a dietary lipid contents of 10% would promote a particular adjustment of the endocrine and autocrine/paracrine GH/IGF system, stimulating body growth and perhaps muscle hyperplasia. On the other hand, a higher dietary lipid content would uncouple the GH/IGF system, reducing hepatic IGF-I, while slightly increasing hepatic GHR-I, probably to prompt lipolysis. Full article
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14 pages, 2576 KiB  
Article
Age, Growth, and Natural Mortality of Graysby, Cephalophilis cruentata, from the Southeastern United States
by Michael L. Burton, Jennifer C. Potts, Andrew D. Ostrowski and Kyle W. Shertzer
Fishes 2019, 4(3), 36; https://doi.org/10.3390/fishes4030036 - 27 Jun 2019
Cited by 4 | Viewed by 3664
Abstract
Graysby (Cephalophilis cruentata) (n = 1308) collected from the southeastern United States Atlantic coast from 2001 to 2016 were aged using sectioned sagittal otoliths. Opaque zones formed February to June (peaking in April). Ages ranged from 2 to 21 years, [...] Read more.
Graysby (Cephalophilis cruentata) (n = 1308) collected from the southeastern United States Atlantic coast from 2001 to 2016 were aged using sectioned sagittal otoliths. Opaque zones formed February to June (peaking in April). Ages ranged from 2 to 21 years, and the largest fish measured 453 mm TL. Growth morph analysis revealed two regionally distinct growth trajectories: von Bertalanffy growth equations were Lt = 388 (1 − e−0.12(t+5.73)) for fish from North Carolina through southeast Florida (northern region), and Lt = 267 (1 − e−0.17(t+6.20)) for fish from the Florida Keys (southern region). When growth was re-estimated using a fixed t0 value of −0.75 to estimate for smaller fish, growth equations were Lt = 349 (1 − e−0.26(t+0.75)) and Lt = 250 (1 − e−0.43(t+0.75)) for fish from the northern and southern regions, respectively. The age-invariant estimate of natural mortality was M = 0.30 for all fish, while age-specific estimates ranged 0.88–0.28 y−1 for fish aged 1–21 from the northern region and 0.89–0.47 y−1 for fish aged 1–15 from the southern region. This study presents the first comprehensive analysis of life-history parameters for graysby from the Atlantic waters off the southeastern United States, including specimens from both recreational and commercial fisheries. Full article
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