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Jose Juan Castrohernandez - One of the best experts on this subject based on the ideXlab platform.
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feeding ecology of the planehead filefish stephanolepis hispidus pisces Monacanthidae in the canary islands area
Revista De Biologia Marina Y Oceanografia, 2015Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan CastrohernandezAbstract:Se examino la ecologia alimentaria de Stephanolepis hispidus, en aguas de las Islas Canarias. El estudio se baso en el contenido estomacal de 823 ejemplares de 8,9 cm a 25,9 cm de longitud total (LT), capturados mensualmente en trampas para peces entre febrero de 1998 y junio de 1999. Aproximadamente el 27,2% de los peces mostraron estomagos vacios. Esta proporcion vario significativamente entre los sexos, pero no entre las clases de tamano o las estaciones evaluadas. La dieta de Stephanolepis hispidus se compone principalmente por hidrozoos, anfipodos, equinodermos y algas. Gastropodos, decapodos y lamelibranquios fueron presas secundarias. De acuerdo con el cambio de la ontogenia, los individuos de pequeno tamano (<12,9 cm LT) se alimentan principalmente de pequenos crustaceos (anfipodos e hidrozoos), mientras que los especimenes de gran tamano consumen equinoideos, algas, crustaceos y lamelibranquios. Hidrozoos y algas son mas importantes en la dieta durante la primavera, y los anfipodos fueron mas importantes en invierno. Los erizos de mar aumentan en verano y otono. Los valores del indice de Morisita indicaron superposicion de la dieta entre individuos de las clases de tallas mas pequenas y mas grande que 12,9 cm LT (S= 0,77). Asimismo, la variacion estacional en la superposicion de la dieta fue alta durante invierno (S= 0,95) y primavera (S= 0,93), pero fue relativamente menor en otono (S= 0,68). Los resultados indicaron que la alimentacion de la especie abarca un estrecho rango de presas con algun grado de selectividad y se compone principalmente por macroinvertebrados.
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reproductive biology of the planehead filefish stephanolepis hispidus pisces Monacanthidae in the canary islands area
Ichthyological Research, 2015Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan CastrohernandezAbstract:The reproductive biology of the planehead filefish, Stephanolepis hispidus, in the waters of the Canary Islands area was studied. The study was conducted with a sample of 906 specimens from 8.9 to 25.9 cm in total length (TL) that were caught in fish traps from February 1998 to August 1999. Females predominated in the catches, and the sex ratio of 1.0:1.4 significantly deviated from the theoretical 1:1 distribution. This ratio varied when calculated by the length classes and by the season. Based on the monthly evolution of the Gonadosomatic Index (GSI) and the proportion of mature individuals, the spawning season occurred between May and October, with a peak in July and August for both sexes. This species accumulates energy reserves in the liver to be spent during the maturation of the gonads and spawning. The mean size at sexual maturity (L50) was 13.9 cm TL in females and 14.9 cm TL in males. The fecundity of S. hispidus fluctuated between 14,071 and 91,323 (mean = 55,239 ± 19,079), and the relative fecundity oscillated between 460 and 1,238 oocytes/g of eviscerated weight (mean = 904 ± 206). The diameter of the oocytes was 0.47 mm (SD = 0.10). The described reproductive characteristics provide options to fishery managers including regulations for spatial and temporal fishing closures to protect the breeding fish during spawning and the selectivity of fishing gears. Thus, it is proposed that fishing be limited to water depths greater than 30 m and that the minimum legal length of fish be established at 18 cm TL.
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feeding ecology of the planehead filefish stephanolepis hispidus pisces Monacanthidae in the canary islands area ecologia trofica de stephanolepis hispidus pisces Monacanthidae en el area de las islas canarias
2015Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan Castrohernandez, Islas CanariasAbstract:The feeding ecology of the planehead filefish, Stephanolepis hispidus, in waters of the Canary Islands was examined. The study was based on the stomach contents of 823 specimens, from 8.9 cm to 25.9 cm in total length (TL), caught monthly in fish traps from February 1998 to June 1999. Approximately 27.2% of the fish showed empty stomachs. This proportion varied significantly between sexes but not among size classes or the evaluated seasons. The food composition of planehead filefish was composed mainly of hydroids, amphipods, echinoids and algae. Gastropods, decapods and l amelibranchs were secondary prey. According to the observed ontogenetic shift, small-sized individuals (< 12.9 cm TL) fed primarily on small c rustaceans (a mphipods and hydroids), whereas large-sized specimens consumed echinoids, alg ae, and lamelibranchs. Hydroids and algae were more important in spring, and amphipods were more important in winter. Echinoids increased in summer and autumn. The values of Morisita's index indicated diet overlapping between individuals of length classes smaller and larger than 12.9 cm TL (S= 0.77). Likewise, the seasonal variation in the diet overlapping was high during winter (S= 0.95) and spring (S= 0.93) but was relatively lower in autumn (S= 0.68). The results indicated that the diet of planehead filefish was characterized by a narrow range of prey items with some degree of selectivity and was composed mainly of macroinvertebrates.
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age and growth of stephanolepis hispidus linnaeus 1766 pisces Monacanthidae in the canary islands area
Fisheries Research, 2003Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan CastrohernandezAbstract:Abstract The growth of the planedhead filefish Stephanolepis hispidus was studied on individuals sampled from a small-scale fishery off Gran Canaria (Canary Islands, central-east Atlantic) between March 1998 and August 1999. The age of the sampled individuals, which ranged from 0 to 3 years, was estimated using both the length frequency distribution and the count of growth rings recorded on the anterior dorsal spine. The mean total length of the 0 age class was 10.9 cm, while the ages classes 1, 2 and 3 showed a mean length of 15.8, 19.4 and 21.4 cm, respectively. Differences in the growth rhythms were observed between the sexes. The asymptotic lengths (L∞) were 25.7 and 27.4 cm for females and males, respectively. The curvature parameter (K) of the von Bertalanffy growth equation was 0.40 per year. The amplitude of the seasonal growth oscillation of the von Bertalanffy growth equation (C=0.15) and the Winter Point (WP=0.19) indicate a seasonality in the growth pattern, being slowest at the end of the winter.
Valerio Visconti - One of the best experts on this subject based on the ideXlab platform.
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geographic variation in life history traits of the long lived monacanthid meuschenia scaber Monacanthidae
Marine Biology, 2020Co-Authors: Valerio Visconti, Edl Trip, Marc H Griffiths, Kendall D ClementsAbstract:Demography and life-history characteristics of reef fishes may vary as a consequence of ecological and environmental factors that lead to changes among populations. We evaluated variation in life-history traits in the leatherjacket Meuschenia scaber (Monacanthidae) through age-based analysis of 2112 fish collected from three locations in New Zealand distributed along an 8° latitudinal and 5 °C SST gradients. Meuschenia scaber showed distinct differences in age structure, growth patterns, maximum size and age, sex ratio and mortality across this latitudinal gradient. At warmer lower latitudes (Hauraki Gulf) the population displayed significantly greater mean adult body size (Lmax) and asymptotic length (L∞) in comparison with the other two locations. Fish from Tasman Bay (mid-range latitude) had a longer life span (Tmax) and a maximum age of 19 years, which represents the longest-lived monacanthid documented to date. Fish from Pegasus Bay (cooler higher latitude) showed a slower initial growth than lower latitude counterparts. The difference in maximum age between the sexes declined clinally from 7 years in the Hauraki Gulf to 3 years in Tasman Bay and 1 year in Pegasus Bay. Meuschenia scaber females tended to display heavier and larger body size than males at all three locations. Sex ratios varied among populations and with depth, suggesting females in the Hauraki Gulf and Tasman Bay may move into deeper water with age. Given the increasing global exploitation of monacanthids in multispecies fisheries and their long-living nature, our results provide valuable age-based demographic information essential for future conservation, monitoring and management programs.
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reproductive biology of the leatherjacket meuschenia scaber Monacanthidae forster 1801 in the hauraki gulf new zealand
New Zealand Journal of Marine and Freshwater Research, 2018Co-Authors: Valerio Visconti, Marc H Griffiths, Elizabeth D L Trip, Kendall D ClementsAbstract:ABSTRACTThe leatherjacket Meuschenia scaber is widely distributed in Australasian waters, and is a valued bycatch of inshore bottom trawl fisheries although little is known of its life history. Here, we describe the reproductive biology of the species based on 651 leatherjackets sampled in the Hauraki Gulf, New Zealand, between July 2014 and March 2016. The maximum total length (LT) recorded for females and males were 320 and 315 mm, respectively, with both sexes present in all size classes. Monthly analysis of gonad condition revealed a clear spawning season from late austral winter to early summer (August–December), and histological analysis of the ovaries revealed that M. scaber is an indeterminate serial spawning gonochorist. The estimated sizes at sexual maturity (L50) for females (189.9 mm LT) and males (188.4 mm LT) did not differ significantly. Relatively small testes, sexual dimorphism and underwater observation of nesting suggest that M. scaber is a paired spawner.
Kendall D Clements - One of the best experts on this subject based on the ideXlab platform.
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geographic variation in life history traits of the long lived monacanthid meuschenia scaber Monacanthidae
Marine Biology, 2020Co-Authors: Valerio Visconti, Edl Trip, Marc H Griffiths, Kendall D ClementsAbstract:Demography and life-history characteristics of reef fishes may vary as a consequence of ecological and environmental factors that lead to changes among populations. We evaluated variation in life-history traits in the leatherjacket Meuschenia scaber (Monacanthidae) through age-based analysis of 2112 fish collected from three locations in New Zealand distributed along an 8° latitudinal and 5 °C SST gradients. Meuschenia scaber showed distinct differences in age structure, growth patterns, maximum size and age, sex ratio and mortality across this latitudinal gradient. At warmer lower latitudes (Hauraki Gulf) the population displayed significantly greater mean adult body size (Lmax) and asymptotic length (L∞) in comparison with the other two locations. Fish from Tasman Bay (mid-range latitude) had a longer life span (Tmax) and a maximum age of 19 years, which represents the longest-lived monacanthid documented to date. Fish from Pegasus Bay (cooler higher latitude) showed a slower initial growth than lower latitude counterparts. The difference in maximum age between the sexes declined clinally from 7 years in the Hauraki Gulf to 3 years in Tasman Bay and 1 year in Pegasus Bay. Meuschenia scaber females tended to display heavier and larger body size than males at all three locations. Sex ratios varied among populations and with depth, suggesting females in the Hauraki Gulf and Tasman Bay may move into deeper water with age. Given the increasing global exploitation of monacanthids in multispecies fisheries and their long-living nature, our results provide valuable age-based demographic information essential for future conservation, monitoring and management programs.
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reproductive biology of the leatherjacket meuschenia scaber Monacanthidae forster 1801 in the hauraki gulf new zealand
New Zealand Journal of Marine and Freshwater Research, 2018Co-Authors: Valerio Visconti, Marc H Griffiths, Elizabeth D L Trip, Kendall D ClementsAbstract:ABSTRACTThe leatherjacket Meuschenia scaber is widely distributed in Australasian waters, and is a valued bycatch of inshore bottom trawl fisheries although little is known of its life history. Here, we describe the reproductive biology of the species based on 651 leatherjackets sampled in the Hauraki Gulf, New Zealand, between July 2014 and March 2016. The maximum total length (LT) recorded for females and males were 320 and 315 mm, respectively, with both sexes present in all size classes. Monthly analysis of gonad condition revealed a clear spawning season from late austral winter to early summer (August–December), and histological analysis of the ovaries revealed that M. scaber is an indeterminate serial spawning gonochorist. The estimated sizes at sexual maturity (L50) for females (189.9 mm LT) and males (188.4 mm LT) did not differ significantly. Relatively small testes, sexual dimorphism and underwater observation of nesting suggest that M. scaber is a paired spawner.
Nestor Javier Mancerarodriguez - One of the best experts on this subject based on the ideXlab platform.
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feeding ecology of the planehead filefish stephanolepis hispidus pisces Monacanthidae in the canary islands area
Revista De Biologia Marina Y Oceanografia, 2015Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan CastrohernandezAbstract:Se examino la ecologia alimentaria de Stephanolepis hispidus, en aguas de las Islas Canarias. El estudio se baso en el contenido estomacal de 823 ejemplares de 8,9 cm a 25,9 cm de longitud total (LT), capturados mensualmente en trampas para peces entre febrero de 1998 y junio de 1999. Aproximadamente el 27,2% de los peces mostraron estomagos vacios. Esta proporcion vario significativamente entre los sexos, pero no entre las clases de tamano o las estaciones evaluadas. La dieta de Stephanolepis hispidus se compone principalmente por hidrozoos, anfipodos, equinodermos y algas. Gastropodos, decapodos y lamelibranquios fueron presas secundarias. De acuerdo con el cambio de la ontogenia, los individuos de pequeno tamano (<12,9 cm LT) se alimentan principalmente de pequenos crustaceos (anfipodos e hidrozoos), mientras que los especimenes de gran tamano consumen equinoideos, algas, crustaceos y lamelibranquios. Hidrozoos y algas son mas importantes en la dieta durante la primavera, y los anfipodos fueron mas importantes en invierno. Los erizos de mar aumentan en verano y otono. Los valores del indice de Morisita indicaron superposicion de la dieta entre individuos de las clases de tallas mas pequenas y mas grande que 12,9 cm LT (S= 0,77). Asimismo, la variacion estacional en la superposicion de la dieta fue alta durante invierno (S= 0,95) y primavera (S= 0,93), pero fue relativamente menor en otono (S= 0,68). Los resultados indicaron que la alimentacion de la especie abarca un estrecho rango de presas con algun grado de selectividad y se compone principalmente por macroinvertebrados.
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reproductive biology of the planehead filefish stephanolepis hispidus pisces Monacanthidae in the canary islands area
Ichthyological Research, 2015Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan CastrohernandezAbstract:The reproductive biology of the planehead filefish, Stephanolepis hispidus, in the waters of the Canary Islands area was studied. The study was conducted with a sample of 906 specimens from 8.9 to 25.9 cm in total length (TL) that were caught in fish traps from February 1998 to August 1999. Females predominated in the catches, and the sex ratio of 1.0:1.4 significantly deviated from the theoretical 1:1 distribution. This ratio varied when calculated by the length classes and by the season. Based on the monthly evolution of the Gonadosomatic Index (GSI) and the proportion of mature individuals, the spawning season occurred between May and October, with a peak in July and August for both sexes. This species accumulates energy reserves in the liver to be spent during the maturation of the gonads and spawning. The mean size at sexual maturity (L50) was 13.9 cm TL in females and 14.9 cm TL in males. The fecundity of S. hispidus fluctuated between 14,071 and 91,323 (mean = 55,239 ± 19,079), and the relative fecundity oscillated between 460 and 1,238 oocytes/g of eviscerated weight (mean = 904 ± 206). The diameter of the oocytes was 0.47 mm (SD = 0.10). The described reproductive characteristics provide options to fishery managers including regulations for spatial and temporal fishing closures to protect the breeding fish during spawning and the selectivity of fishing gears. Thus, it is proposed that fishing be limited to water depths greater than 30 m and that the minimum legal length of fish be established at 18 cm TL.
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feeding ecology of the planehead filefish stephanolepis hispidus pisces Monacanthidae in the canary islands area ecologia trofica de stephanolepis hispidus pisces Monacanthidae en el area de las islas canarias
2015Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan Castrohernandez, Islas CanariasAbstract:The feeding ecology of the planehead filefish, Stephanolepis hispidus, in waters of the Canary Islands was examined. The study was based on the stomach contents of 823 specimens, from 8.9 cm to 25.9 cm in total length (TL), caught monthly in fish traps from February 1998 to June 1999. Approximately 27.2% of the fish showed empty stomachs. This proportion varied significantly between sexes but not among size classes or the evaluated seasons. The food composition of planehead filefish was composed mainly of hydroids, amphipods, echinoids and algae. Gastropods, decapods and l amelibranchs were secondary prey. According to the observed ontogenetic shift, small-sized individuals (< 12.9 cm TL) fed primarily on small c rustaceans (a mphipods and hydroids), whereas large-sized specimens consumed echinoids, alg ae, and lamelibranchs. Hydroids and algae were more important in spring, and amphipods were more important in winter. Echinoids increased in summer and autumn. The values of Morisita's index indicated diet overlapping between individuals of length classes smaller and larger than 12.9 cm TL (S= 0.77). Likewise, the seasonal variation in the diet overlapping was high during winter (S= 0.95) and spring (S= 0.93) but was relatively lower in autumn (S= 0.68). The results indicated that the diet of planehead filefish was characterized by a narrow range of prey items with some degree of selectivity and was composed mainly of macroinvertebrates.
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age and growth of stephanolepis hispidus linnaeus 1766 pisces Monacanthidae in the canary islands area
Fisheries Research, 2003Co-Authors: Nestor Javier Mancerarodriguez, Jose Juan CastrohernandezAbstract:Abstract The growth of the planedhead filefish Stephanolepis hispidus was studied on individuals sampled from a small-scale fishery off Gran Canaria (Canary Islands, central-east Atlantic) between March 1998 and August 1999. The age of the sampled individuals, which ranged from 0 to 3 years, was estimated using both the length frequency distribution and the count of growth rings recorded on the anterior dorsal spine. The mean total length of the 0 age class was 10.9 cm, while the ages classes 1, 2 and 3 showed a mean length of 15.8, 19.4 and 21.4 cm, respectively. Differences in the growth rhythms were observed between the sexes. The asymptotic lengths (L∞) were 25.7 and 27.4 cm for females and males, respectively. The curvature parameter (K) of the von Bertalanffy growth equation was 0.40 per year. The amplitude of the seasonal growth oscillation of the von Bertalanffy growth equation (C=0.15) and the Winter Point (WP=0.19) indicate a seasonality in the growth pattern, being slowest at the end of the winter.
Geoffrey P Jones - One of the best experts on this subject based on the ideXlab platform.
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diversity and functional importance of coral feeding fishes on tropical coral reefs
Fish and Fisheries, 2008Co-Authors: Andrew J Cole, Morgan S Pratchett, Geoffrey P JonesAbstract:Fishes that feed from live corals (corallivores) are a conspicuous component of healthy coral reef environments. However, knowledge of the occurrence and ecological significance of this feeding mode is fragmentary. Historically, very few fish were considered capable of feeding from live coral, and those few that did were considered ecologically insignificant. More recently, the role of corallivores has been re-evaluated; published records document 128 corallivorous fish species from 11 different families, with 69 of these belonging to the family Chaetodontidae. Other families, including the Labridae, Tetraodontidae, Balistidae, Monacanthidae, Poma-centridae and Scaridae, all have between seven and ten coral-feeding species. One-third of coral-feeding fishes feed almost exclusively on corals, with more than 80% of their diet based on coral. Corallivorous fish show distinct prey preferences and consume only a small subset of available corals, usually the genera Acropora, Pocillopora and Porites. This selective predation by corallivores can limit abundance and distribution of preferred corals. Chronic predation by corallivores may also exacerbate effects of coral disturbance (e.g. climate-induced coral bleaching), impeding reef recovery and causing further coral loss. Conversely, the cover of preferred corals can be a primary determinant of corallivore abundance and physiological condition. Owing to this close association, obligate corallivores invariably decline in response to loss of coral cover. Increased knowledge of the number of corallivores and their diets suggest that this feeding mode is more important to coral reef food webs than traditionally thought.