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Temporal and spatial dynamics of Lutjanus cyanopterus (Pisces: Lutjanidae) and L. jocu spawning aggregations in the United States Virgin Islands
Kadison,Elizabeth; Nemeth,Richard S; Herzlieb,Steve; Blondeau,Jeremiah;
Revista de Biología Tropical , 2006,
Abstract: the grammanik bank is a deep reef (35-40 m) located approximately 14 km south of st. thomas usvi, on the southern edge of the puerto rico shelf. the relatively narrow 1.5 km long reef annually hosts spawning aggregations of several species of groupers, snappers and jacks. until february of 2005, when temporary seasonal protection was offered by the caribbean fisheries management council, the bank was subject to moderate or heavy exploitation from fishers. cubera snapper (lutjanus cyanopterus) were observed aggregating on the grammanik bank in relatively large numbers from 2003 to 2005 and dog snapper (l. jocu) aggregations were observed in 2005. the arrival and departure of these aggregations appeared to be seasonal and to revolve around the moon phase. cubera snapper spawning seasonality coincided with that elsewhere in the caribbean and off south florida. schools of up to 1000 fish of each species were observed as well as pre-spawning behavior and milt release. aggregations of both species showed high site fidelity within seasons but cubera snapper aggregations sites moved between seasons. the authors recommend year-round closure of the grammanik bank based on its importance as critical fish habitat and a multi-species aggregation area. rev. biol. trop. 54 (suppl. 3): 69-78. epub 2007 jan. 15.
Temporal and spatial dynamics of Lutjanus cyanopterus (Pisces: Lutjanidae) and L. jocu spawning aggregations in the United States Virgin Islands  [cached]
Elizabeth Kadison,Richard S Nemeth,Steve Herzlieb,Jeremiah Blondeau
Revista de Biología Tropical , 2006,
Abstract: The Grammanik bank is a deep reef (35-40 m) located approximately 14 km south of St. Thomas USVI, on the southern edge of the Puerto Rico shelf. The relatively narrow 1.5 km long reef annually hosts spawning aggregations of several species of groupers, snappers and jacks. Until February of 2005, when temporary seasonal protection was offered by the Caribbean Fisheries Management Council, the bank was subject to moderate or heavy exploitation from fishers. Cubera snapper (Lutjanus cyanopterus) were observed aggregating on the Grammanik bank in relatively large numbers from 2003 to 2005 and dog snapper (L. jocu) aggregations were observed in 2005. The arrival and departure of these aggregations appeared to be seasonal and to revolve around the moon phase. Cubera snapper spawning seasonality coincided with that elsewhere in the Caribbean and off south Florida. Schools of up to 1000 fish of each species were observed as well as pre-spawning behavior and milt release. Aggregations of both species showed high site fidelity within seasons but cubera snapper aggregations sites moved between seasons. The authors recommend year-round closure of the Grammanik bank based on its importance as critical fish habitat and a multi-species aggregation area. Rev. Biol. Trop. 54 (Suppl. 3): 69-78. Epub 2007 Jan. 15. El banco Grammanik es un arrecife profundo (35-40 m) ubicado aproximadamente 14 km al Sur de St. Thomas (Islas Vírgenes EUA), en el límite sur de la plataforma de Puerto Rico. Este arrecife relativamente angosto y de 1.5 km de longitud, recibe anualmente agrupaciones de varias especies de meros, pargos y jureles, durante sus desoves. Fue objeto de explotación de moderada a alta por parte de los pescadores hasta febrero del 2005, cuando el Consejo de Pesca del Caribe le ofreció protección temporal. El pargo cubera (Lutjanus cyanopterus) fue observado en el banco Grammanik en agrupaciones numerosas entre el a o 2003 y el 2005, a su vez, agrupaciones del pargo perro o pargo caucha (L. jocu) se observaron en el 2005. La llegada y partida de estos grupos parece ser estacional y estar relacionada con la fase lunar. El desove estacional del pargo cubera coincide con informes de otros sitios del Caribe y al Sur de la Florida, donde se observaron cardúmenes de hasta 1000 peces de cada especie, así como comportamientos previos al desove y liberación de esperma. Agrupaciones de ambas especies mostraron alta fidelidad al sitio en una misma estación, pero los sitios de agrupación del pargo cubera cambiaron entre estaciones. Los autores recomiendan el cierre del banco Gammani
Can Lutjanus purpureus (South red snapper) be "legally" considered a red snapper (Lutjanus campechanus)?
Gomes, Grazielle;Schneider, Horacio;Vallinoto, Marcelo;Santos, Simoni;Orti, Guillermo;Sampaio, Iracilda;
Genetics and Molecular Biology , 2008, DOI: 10.1590/S1415-47572008000200035
Abstract: red snappers (lutjanus purpureus in brazil and lutjanus campechanus in usa and gulf of mexico) are both under clear effect of overfishing. because of their high morphological similarity it has already been suggested that they could possibly be considered as a single species. to investigate the degree of similarity and the genetic structure of red snapper populations we constructed a common dataset of partial d-loop mtdna sequences of l. purpureus from brazil (amapá, pará and maranh?o) and l. campechanus from the atlantic coast of the usa (florida, louisiana and mississippi). phylogenetic and population genetic analyses surprisingly depicted high similarity between l. campechanus and l. purpureus, compatible with the hypothesis of a single species of red snapper for the western atlantic ocean. these preliminary but very curious findings open an important discussion regarding the legislation involved on the capture of this overexploited fish resources as well as regarding their taxonomy.
The use of three anaesthetics for handling spotted rose snapper Lutjanus guttatus (Pisces, Lutjanidae) broodstock
Ibarra-Zatarain,Zohar; Ibarra-Castro,Leonardo; Alvarez-Lajonchère,Luis; García Aguilar,Noemi; Sánchez-Téllez,Juan Luis;
Revista de biología marina y oceanografía , 2011, DOI: 10.4067/S0718-19572011000300016
Abstract: benzocaine, 2-phenoxyethanol and ms-222 were tested as anaesthetics for several handling procedures with spotted rose snapper lutjanus guttatus broodstock. significant differences in time for induction and recovery were found with specific doses, as well as a direct correlation between the dose and the induction time. each procedure demanded specific anaesthesia levels where the stage of deep anaesthesia should not be surpassed. the most effective agent for inducing deep anaesthesia was ms-222, with the least amount of time required for induction and recovery when using 100 mg l-1. it was followed by 250 μl l-1 of 2-phenoxyethanol, which was less costly.
Population characteristics of spotted rose snapper lutjanus guttatus caught as shrimp bycatch in the gulf of California
González-Ochoa,Oscar A; López-Martínez,Juana; Hernández-Saavedra,Norma Yolanda;
Interciencia , 2009,
Abstract: there are limited population biology studies of the spotted rose snapper lutjanus guttatus. adults of this highly valued commercial species are fished with gillnets and hook-and-line, while juveniles are caught as shrimp bycatch and usually discarded. the effects of this practice have not been studied. as a first step, this study assessed some population parameters of juvenile snapper caught by the gulf of california shrimp fishery. we looked for early growth stages and determined by the least squares method the weight to standard length relationship as w= 0.000092, sl3.0509. length frequency distributions were constructed; using the elefan i method, von bertalanffy growth parameters were found to be l¥= 515mm (standard length) and k= 0.13. natural mortality (m= 0.35) was estimated from pauly?s empirical and ralston equations; and total mortality was calculated by the catch curve equation. the recruitment pattern extended throughout the year, with spring and summer peaks. the sex ratio was 1:1 and the length at capture was 80mm (standard length). with an apparently high fishing mortality levels, it is recommended that abundance and distribution studies be performed to determine the impact of shrimp fishing on this population.
Reproduction of the fish Lutjanus analis (mutton snapper; Perciformes: Lutjanidae) from Northeastern Brazil
Teixeira,Simone F; Duarte,Yalan F; Ferreira,Beatrice P;
Revista de Biología Tropical , 2010,
Abstract: the mutton snapper lutjanus analis is an overexploited species of economic importance for the northeast region of brazil. to determine the reproductive aspects of the mutton snapper, biological data were sampled from bahia, pernambuco, paraíba, rio grande do norte and ceará states, between 7 and 200m depth, from february 1997 to december 1999, performed in the brazilian economic exclusive zone study program (revizee-ne program). data on total length (tl), fork length (fl), standard length (sl), total weight (tw) and gutted weight (gw) were measured. the gonads were collected and fixed in faacc for histological analysis on maturational stage and calculation of the gonadosomatic index (gsi). a total of 135 fishes were collected; from these, 74 were females and 61 were males. females were between 28.0 and 69.0cm (tl) and the males between 35.0 and 75.0cm (tl). mutton snapper are gonochorists, and the spawning season, determined by the maturity stages frequency and the gsi, occurred between november and april, with peak spawning in march. the mature females’ minimum length was 28.0cm fork length, smaller than the minimum maturation length previously reported for the species in cuba. the exploitation status of the species and the biological traits enhances the importance of establishing spatial and seasonal protection measures such as protected areas both in nursery and spawning sites. rev. biol. trop. 58 (3): 791-800. epub 2010 september 01.
Reproduction of the fish Lutjanus analis (mutton snapper; Perciformes: Lutjanidae) from Northeastern Brazil
Simone F Teixeira,Yalan F Duarte,Beatrice P Ferreira
Revista de Biología Tropical , 2010,
Abstract: The mutton snapper Lutjanus analis is an overexploited species of economic importance for the Northeast region of Brazil. To determine the reproductive aspects of the mutton snapper, biological data were sampled from Bahia, Pernambuco, Paraíba, Rio Grande do Norte and Ceará States, between 7 and 200m depth, from February 1997 to December 1999, performed in the Brazilian Economic Exclusive Zone Study Program (REVIZEE-NE Program). Data on total length (TL), fork length (FL), standard length (SL), total weight (TW) and gutted weight (GW) were measured. The gonads were collected and fixed in FAACC for histological analysis on maturational stage and calculation of the gonadosomatic index (GSI). A total of 135 fishes were collected; from these, 74 were females and 61 were males. Females were between 28.0 and 69.0cm (TL) and the males between 35.0 and 75.0cm (TL). Mutton snapper are gonochorists, and the spawning season, determined by the maturity stages frequency and the GSI, occurred between November and April, with peak spawning in March. The mature females’ minimum length was 28.0cm fork length, smaller than the minimum maturation length previously reported for the species in Cuba. The exploitation status of the species and the biological traits enhances the importance of establishing spatial and seasonal protection measures such as protected areas both in nursery and spawning sites. Rev. Biol. Trop. 58 (3): 791-800. Epub 2010 September 01. El pargo criollo Lutjanus analis es una especie de importancia económica para la región noreste de Brasil, que esta siendo sobreexplotada. Para determinar sus aspectos reproductivos, se tomaron datos biológicos en los Estados de Bahía, Pernambuco, Paraíba, Rio Grande do Norte y Ceará, entre 7 y 200m de profundidad, de febrero 1997 a diciembre 1999, en el Programa de REVIZEE-NE en la Zona Económica Exclusiva de Brasil. Se midieron la longitud total (LT), longitud de horquilla (FL), longitud estándar (SL), el peso total (TW) y peso evicerado (GW). Las gónadas se recolectaron y fijaron en FAACC para el análisis histológico de las etapas de maduración y el cálculo del índice gonadosomático (IGS). Se recolectaron un total de 135 hembras y 61 machos. Las hembras midieron 28.0-69.0cm (TL) y los machos entre 35.0-75.0cm (TL). Lutjanus analis es gonocorista, y la época de desove, determinada por la frecuencia de las etapas de maduración y el GSI, ocurre entre noviembre y abril, con con un pico de desove en marzo. La longitud mínima (FL) de las hembras maduras fue 28.0cm, menor que la reportada para la especie en Cuba. El estado
Feeding ecology of juvenile dog snapper Lutjanus jocu (Bloch and Shneider, 1801) (Lutjanidae) in intertidal mangrove creeks in Curu?á estuary (Northern Brazil)
Monteiro, Dijane Pantoja;Giarrizzo, Tommaso;Isaac, Victoria;
Brazilian Archives of Biology and Technology , 2009, DOI: 10.1590/S1516-89132009000600014
Abstract: the diet and feeding ecology of juvenile dog snapper (lutjanus jocu) were investigated in 92 specimens collected in four intertidal mangrove creeks of curu?á estuary, northern brazil, between september 2003 and july 2004. no significant differences in total length were found between the sampling months. feeding intensity was high as indicated by high stomach fullness index and low vacuity index. the most important prey was penaeidae, followed by grapsidae and porcellanidae. the diet of juvenile dog snapper showed clear seasonal differences. specimens from dry season (september and november) and dry / wet season transition (january), were specialists feeding exclusively on penaeidae. however, the specimens from wet season (march and may) and wet /dry season transition (july) that consumed mainly grapsidae, penaeidae and porcellanidae were generalist. these seasonal changes in diet could be related to variations in food availability.
Reproduction of the Brazilian snapper, Lutjanus alexandrei Moura & Lindeman, 2007 (Perciformes: Lutjanidae), off the northern coast of Pernambuco, Brazil
Fernandes, Cezar A. F.;Oliveira, Paulo G. V. de;Travassos, Paulo E. P.;Hazin, Fábio H. V.;
Neotropical Ichthyology , 2012, DOI: 10.1590/S1679-62252012005000022
Abstract: reproductive aspects of the brazilian snapper lutjanus alexandrei, were characterized, including a description of the development of oocytes and spermatogenic cells, size at first sexual maturity, and fecundity. a total of 540 fish were analyzed with 250 having their gonads sectioned to allow microscopic evaluation. six maturity stages were identified for females and males: immature, maturing, mature, spawning, spawned, and resting. fish standard length (sl) varied from 13.0 to 28.3 cm and sex ratio was 1.6 males: 1.0 females. monthly distributions of mean gonadosomatic index (gsi) and maturity stages suggest that spawning occurs mainly in a protracted period, during the warmer months, from november to march. the size of first sexual maturity was estimated at 17.1 cm sl for females and 16.8 cm sl for males. oocyte development suggests that l. alexandrei exhibits a multiple batch spawning behavior and batch fecundity varied from 34,000 to 324,000 oocytes.
Food habits of the yellow snapper Lutjanus argentiventris (Peters, 1869) (Percoidei: Lutjanidae) in La Paz Bay, Mexico
Vázquez,Rosa I; Rodríguez,Jesús; Abitia,Leonardo A; Galván,Felipe;
Revista de biología marina y oceanografía , 2008, DOI: 10.4067/S0718-19572008000200008
Abstract: a total of 304 yellow snapper lutjanus argentiventris stomachs were sampled bimonthly from april 2003 to april 2004, of which 44% contained food. we identified 54 prey species. from the index of relative importance (iri), fish eggs (62%), harengula thrissina (23%), porichthys margaritatus (3.3%), and abudefduf troschelii (2.3%) were the prey of greatest importance in its trophic spectrum. in juvenile snappers, the most important preys were unidentified organic matter (32%), the crustacean upogebia pugettensis (29%), penaeid shrimp (6.5%), and fish eggs (5.2%). the levin index determined that the diet breadth was low (bi=0.0002), indicating that it is a specialist predator showing preference for fish eggs and h. thrissina. the same result was found in males (bi=0.0002) and females (bi = 0.0009). although juveniles also showed a low trophic breadth, they preferred unidentified organic matter and u. pugettensis. the morisita-horn index showed considerable overlap in diet between genders (cλ>0.6), though diet overlap was low between juveniles and adults (cλ<0.2) reflecting feeding habitat differences between them.
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