Ciencias Marinas最新文献

{"title":"Trophic interactions between the 11 most abundant demersal fish species on the Pacific coast of central Mexico","authors":"J. F. Ortega, E. G. Domínguez, G. G. Sansón","doi":"10.7773/cm.v46i2.3056","DOIUrl":"https://doi.org/10.7773/cm.v46i2.3056","url":null,"abstract":"espanolSe realizo la descripcion de la dieta, la estrategia alimenticia y las interacciones troficas de las 11 especies de peces demersales con mayor abundancia en la costa central mexicana del Pacifico durante 2 periodos, el calido y el frio. En total se recolectaron 4,547 estomagos, de los cuales 1,921 estomagos vacios fueron descartados. En el analisis de los contenidos estomacales fueron identificados 95 entidades alimenta-rias, que fueron agrupados en 70 categorias alimentarias pertenecientes a crustaceos, moluscos, peces, poliquetos y equinodermos. De acuerdo a los valores del indice de Smith y la alta diversidad de presas, la estrategia alimenticia mostrada por las 11 especies en ambas temporadas de estudio fue generalista-oportunista. Se registraron valores bajos en la superposicion de la dieta y solamente se encontraron pocos casos signi-ficativos de superposicion de la dieta en la interaccion entre algunas especies de rayas de la familia Urotrygonidae y los lenguados del orden Pleuronectiformes. La disponibilidad y abundancia de recursos presa en el ambiente y la generalizacion de la amplitud del nicho permiten la coexistencia de la comunidad demersal de depredadores de fondos blandos someros sin competencia evidente por los recursos troficos. EnglishWe describe the diet, feeding strategy, and trophic interactions between the 11 most abundant demersal fish species on the Pacific coast of central Mexico during both the warm and cold seasons. A total of 4,547 stomachs were collected, with 1,921 empty stomachs being discarded. According to the stomach content analysis, 95 prey items were identified and grouped into 70 food categories belonging to crusta-ceans, mollusks, fish, polychaetes, and echinoderms. The Smith index value and high prey diversity indicated that the 11 fish species exhibited a generalist opportunistic feeding strategy in both survey seasons. Low values of dietary overlap were recorded, and only a few significant cases of dietary overlap were found in the interaction between some rays (Urotrygonidae) and flatfish species (Pleuronectiformes). The availability and abundance of prey resources in the environment and the generalization of niche breadth allows the demersal predator community of the soft shallow bottoms to coexist without any evident competition for trophic resources.","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":"46 1","pages":"101-117"},"PeriodicalIF":0.7,"publicationDate":"2020-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42635492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gene expression plasticity in Pocillopora corals from 2 locations on the Carrizales Reef, Pacific coast of Mexico","authors":"Manuel A. Delgadillo Nuño, Marco A. Liñán Cabello, Erick Delgadillo Nuño, Clara E. Galindo Sanchez, E. C. Ituarte","doi":"10.7773/cm.v46i2.3062","DOIUrl":"https://doi.org/10.7773/cm.v46i2.3062","url":null,"abstract":"espanolActualmente, la mayor amenaza que enfrentan los corales escleractinios es el cambio climatico acelerado. Suponiendo que la mayoria de los escleractinios son incapaces de una respuesta de adaptacion a los rapidos cambios globales, una respuesta alternativa seria la plasticidad fenotipica, que se describe clasicamente como aclimatacion. Con el fin de establecer una linea base para el estudio de la aclima-tacion en los corales de la costa mexicana del Pacifico, en el presente trabajo evaluamos la plasticidad de la respuesta fisiologica y molecular de 36 colonias pertenecientes a 3 morfoespecies del genero Pocillopora (Pocillopora cf. capitata, Pocillopora cf. damicornis y Pocilloporacf. verrucosa), ubicadas en 2 sitios (este y oeste) del arrecife Carrizales. Los datos ambientales revelaron mayor incidencia de luz y concen-traciones mas altas de clorofila en las muestras de agua del sitio oeste, lo que sugiere la presencia de al menos 2 microambientes con mayor y menor luz en el arrecife. Como respuesta, las morfoespecies del sitio oeste mostraron una mayor expresion genica y diferencias significativas en el contenido de pigmentos, la densidad de endosimbiontes y los marcadores metabolicos (ARN, ADN y proteinas). Dada la preocupacion por el futuro de los arrecifes, consideramos que el presente estudio puede servir como linea base para el estudio de la plasticidad fisiologica y molecular de los corales Pocillopora de Mexico, y con ello se podran desarrollar estrategias de conservacion para las morfoespecies clave en los arrecifes coralinos de la costa mexicana del Pacifico. EnglishThe greatest threat scleractinian corals face today is accelerated climate change. Assuming that most scleractinians are incapable of genetic adaptation to rapid global changes, the alternative response would be phenotypic plasticity, which is classically described as accli-matization. With the purpose of establishing a baseline for the study of acclimatization in corals of the Pacific coast of Mexico, we assessed the molecular and physiological response of 36 colonies of 3 Pocillopora morphospecies (Pocillopora cf. capitata, Pocillopora cf. damicornis, and Pocillopora cf. verrucosa) located at 2 sites (east and west) on Carrizales Reef. Our results show higher incidence of light and chlorophyll concentrations in seawater samples from the west side, suggesting the presence of at least 2 microenvironments with more and less light in the reef. In response, coral morphospecies from the west side showed higher gene expression and significant differences in pigment concentra-tions, endosymbiont densities, and metabolic markers (RNA, DNA, and proteins). Given the present concern about the future of coral reefs, we consider that the present study could be used as a baseline for the study of the physiological and molecular plasticity of Pocillopora corals in Mexican waters, so conservation strategies could be developed for key morphospecies in coral reefs on the Pacific coast","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":"46 1","pages":"89-100"},"PeriodicalIF":0.7,"publicationDate":"2020-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48370177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A spatially explicit model for predicting the probability of oc currence of zero-catch quadrants in the tuna purse seine fishery of the Eastern Tropical Pacific Ocean","authors":"Emigdio Marín-Enríquez","doi":"10.7773/cm.v46i1.3026","DOIUrl":"https://doi.org/10.7773/cm.v46i1.3026","url":null,"abstract":"espanolLos lances nulos (lances en donde la captura retenida es cero) ocurren de manera comun en las pesquerias de tunidos alrededor del mundo. La evidencia actual sugiere que existen distintos factores ambientales que pueden influir en la ocurrencia de este tipo de lances. En el presente trabajo se utilizo una base de datos historica (2003–2015) de la pesqueria de tunidos que opera con red de cerco en el Pacifico Tropical Oriental. Se analizo la variabilidad espaciotemporal de la ocurrencia de cuadrantes de 1o × 1o en donde la captura retenida fue cero (“cuadrantes nulos”). Se ajusto un modelo aditivo generalizado logistico para predecir la ocurrencia de los cuadrantes nulos en funcion de distintas variables ambientales y operacionales. Los resultados sugirieron que existen 2 zonas con alta probabilidad de ocurrencia de cuadrantes nulos, las cuales son muy diferentes desde el punto de vista ambiental: la entrada al golfo de California, Mexico, y frente a la costa de Centroamerica. El modelo estadistico final sugirio que los factores operacionales (numero de lances, indicador de pesca) son mas importantes para determinar la ocurrencia de cuadrantes nulos que los factores ambientales (temperatura superficial del mar, concentracion de clorofila, anomalia del nivel del mar, y eventos El Nino). EnglishNull purse seine sets (those in which the catch is zero) are common in every tuna fishery in the world. Current evidence suggests that different environmental factors can influence the occurrence of null sets. In this study, we used a long-term (2003–2015) database from the tuna purse seine fishery in the eastern Pacific Ocean to analyze the temporal and spatial variability of the occurrence of 1o × 1o quadrants where the retained tuna catch was zero (“null cells”). We fitted a logistic generalized additive model to predict the occurrence of null cells as a function of environmental and operational covariates. Results of the modeling process suggested that high probabilities of null cell occurrence exist mainly in 2 environmentally different zones: the entrance to the Gulf of California, Mexico, and off the coast of Central America. The final statistical model suggested that operational variables (number of sets, type of fishing indicator) are more important to null cell occurrence than environmental factors (sea surface temperature, chlorophyll concentration, sea level anomaly, and El Nino events).","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":"46 1","pages":"19-38"},"PeriodicalIF":0.7,"publicationDate":"2020-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43303241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short-term changes in demersal fish assemblages exploited by an artisanal set gill net fishery in the Caribbean Sea (Colombia)","authors":"C. Salazar-Pérez","doi":"10.7773/cm.v46i1.3041","DOIUrl":"https://doi.org/10.7773/cm.v46i1.3041","url":null,"abstract":"A basic input for implementing ecosystem-based management measures is the knowledge on fish assemblages exploited by multispecies fisheries, such as the set gill net artisanal fishery in the Gulf of Salamanca (GoS), Caribbean Sea (Colombia), which catches a large \u0000number of high-value demersal species. Assemblages of this type were identified in this study, and significant differences ( \u0000P < 0.01) between \u0000sampling periods (2008 and 2013) and seasons were found by means of a two-way permutational multivariate analysis of variance. These \u0000results were consistent with those obtained with the principal \u0000coordinates analysis, indicating the occurrence of short-term structural changes in \u0000these assemblages. Interannual and seasonal variations in discriminant and typifying species were also identified using similarity percentages, \u0000and a decreasing trend in landing per unit effort was established by the bootstrap method. On the other hand, both the geographic location of \u0000the fishing grounds and the characterization of historical changes in the set gill nets used in the GoS were determined using \u0000the traditional \u0000ecological knowledge of local fishermen, who reported a decrease in mesh sizes. In conclusion, temporal variations could be related to changes \u0000in the gill nets, the fishing trip schedules, and the spatial distribution of fishing effort, all which occurred in response to the decrease in catch \u0000rates in traditional fishing grounds.","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":"46 1","pages":"39-56"},"PeriodicalIF":0.7,"publicationDate":"2020-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44972414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artisanal elasmobranch fisheries of northwestern Baja Californi a, Mexico","authors":"O. Santana‐Morales","doi":"10.7773/cm.v46i1.3023","DOIUrl":"https://doi.org/10.7773/cm.v46i1.3023","url":null,"abstract":"espanolLa composicion especifica de elasmobranquios y su variabilidad espaciotemporal en una region marina frecuentemente pueden ser caracterizadas mediante el muestreo de los desembarques de la pesqueria local, lo que puede tener implicaciones para su manejo. En el presente estudio, describimos la composicion de los desembarques de elasmobranquios en 4 principales puertos pesqueros artesanales en el noroeste de Baja California, Mexico. Los muestreos se realizaron de manera oportunista entre 1995 y 2010 e implicaron un esfuerzo de 684 dias de pesca. La composicion especifica dependio del arte de pesca y de la zona de pesca, con el dominio del tiburon zorro comun ( Alopias vulpinus ) y el tiburon perro espinoso ( Squalus suckleyi ) en las capturas con redes agalleras en la zona costera y el dominio del tiburon azul ( Prionace glauca ) y el tiburon mako ( Isurus oxyrhinchus ) en la captura con palangre en la zona oceanica. El analisis de la estructura de tallas indico que la captura de la mayoria de las especies estuvo compuesta, principalmente, por organismos juveniles, aunque la captura de individuos maduros de tiburon sulfin ( Galeorhinus galeus ) mostro un incremento en la pesca con palangre durante el invierno. Los resultados indican que puede haber diferencias regionales menores en la composicion especifica de elasmobranquios a lo largo de la costa pacifica de Baja California, lo cual podria estar relacionado con diferencias oceanograficas o de habitat entre regiones. El resultado de este estudio puede formar la base de futuros esfuerzos para monitorear los cambios en la composicion de las especies a lo largo del tiempo y, asi, evaluar de una manera mas completa las poblaciones de elasmobranquios. EnglishElasmobranch species composition and spatiotemporal variability can often be characterized from landing surveys of local fisheries, with important management implications. In the present study, we describe the elasmobranch landing composition of 4 major artisanal fishing ports in northwestern Baja California, Mexico. Sampling was conducted opportunistically between 1995 and 2010 and included an effort of 684 fishing days. Species composition was gear-dependent and varied with the fishing area, with thresher sharks ( Alopias vulpinus ) and spiny dogfish ( Squalus suckleyi ) dominating the catches landed by coastal gill net fisheries, and blue sharks ( Prionace glauca ) and shortfin mako sharks ( Isurus oxyrhinchus ) dominating the catches landed by the offshore longline fishery. Size-structure analysis indicated that catches were composed primarily of juveniles for most species, although the catch of mature soupfin sharks ( Galeorhinus galeus ) increased in longline fisheries during the winter. The results indicate that minor regional differences in elasmobranch species composition occur along the Pacific coast of Baja California and are most likely related to regional oceanographic or habitat differences. The results of this study may form th","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":"46 1","pages":"1-18"},"PeriodicalIF":0.7,"publicationDate":"2020-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46467693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Size, weight, and diet of the invasive lionfish Pterois volitans (Linnaeus, 1758) on the southern coast of Veracruz, Gulf of Mexico","authors":"R. Aguilar‐Medrano","doi":"10.7773/cm.v46i1.3012","DOIUrl":"https://doi.org/10.7773/cm.v46i1.3012","url":null,"abstract":"espanolLa invasion del pez leon del Indo-Pacifico Pterois volitans ha producido impactos perjudiciales sobre la biodiversidad regional y las pesquerias de zonas invadidas. Para comprender el efecto que puede tener el pez leon en las comunidades nativas, es necesario conocer sus habitos alimenticios. Los objetivos de este estudio fueron documentar nuevos registros de distribucion de P. volitans a lo largo de la costa sur de Veracruz (Mexico), documentar los habitos alimenticios de los especimenes recolectados y determinar si existia una relacion entre la dieta, la talla y el peso de estos especimenes. La densidad de P. volitans en nuestra area de estudio fue baja. La composicion de la dieta de esta especie consistio en peces oseos (95.40%), crustaceos (4.20%) y moluscos (0.36%). La talla y el peso del pez leon estuvieron positivamente correlacionados. No encontramos diferencias estadisticas entre la dieta y los grupos de talla/peso; sin embargo, los especimenes de menor talla, aparentemente, tuvieron una dieta mas variada que los especimenes de mayor talla. EnglishThe invasion of the Indo-Pacific lionfish Pterois volitans has produced detrimental impacts on the regional biodiversity and fisheries of invaded ranges. To understand the effect this lionfish may have on the native fish communities, it is necessary to understand its feeding habits. The objectives of this study were to report new distribution records of P. volitans along the southern coast of Veracruz (Mexico), to document the feeding habits of the collected specimens, and to determine if there was a relationship between the diet, size, and weight of those specimens. The density of P. volitans in our study area was low. Diet composition for this species consisted of bony fishes (95.40%), crustaceans (4.20%), and mollusks (0.36%). Lionfish size and weight were positively correlated. We did not find statistical differences between the diet and the size/weight groupings; however, the smaller specimens seemingly had a more varied diet than the larger specimens.","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2020-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49140412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elasmobranch species in the artisanal fishery of Sucre State, Venezuela","authors":"R. Márquez, R. Tavares, Luis Ariza","doi":"10.7773/cm.v45i4.3018","DOIUrl":"https://doi.org/10.7773/cm.v45i4.3018","url":null,"abstract":"espanolEn Venezuela existe una importante diversidad de especies de elasmobranquios. Sin embargo, existe escasa informacion con relacion a estos en la mayor parte de las regiones costeras. Los objetivos del presente estudio fueron determinar la composicion de especies en la captura de la pesca artesanal del estado Sucre, Venezuela, y analizar la estructura de tallas por sexo para las especies mas comunes. Durante el periodo de estudio (enero de 2016–septiembre de 2017) se realizaron visitas a las principales areas de comercializacion de la ciudad de Cumana, estado de Sucre, y se cuantificaron un total de 2,167 elasmobranquios pertenecientes a 24 especies (15 tiburones y 9 rayas). Las especies de elasmobranquios mas frecuentemente capturadas fueron Mustelus higmani (36.2%), Mustelus canis (18.0%), Hypanus guttatus (15.1%) y Hypanus americanus (7.1%). Los intervalos de tallas (longitud total [LT], diametro de disco [DD]) registrados para estas especies fueron 29.3–73.7 cm LT, 34.0–86.0 cm LT, 17.0–138.0 cm DD y 48.0–108.0 cm DD, respectivamente. Segun las evaluaciones de conservacion a nivel nacional (criterios de la Union Internacional para la Conservacion de la Naturaleza), 7 de las especies registradas en el area de estudio ( M. higmani , Carcharhinus limbatus , Carcharhinus falciformis , Isurus oxyrinchus , Alopias superciliosus , Prionace glauca y Aetobatus narinari ) se encuentran en estado vulnerable, mientras que el resto de las especies ( n = 17) no han sido evaluadas. En Venezuela, actualmente, existe una gran deficiencia en materia de conservacion debido al colapso de las instituciones encargadas de la administracion pesquera. Ello conlleva el incumplimiento de las normativas de pesca disenadas para los elasmobranquios. En el futuro se debera hacer un gran esfuerzo para continuar generando informacion; sin embargo , los avances futuros en materia de investigacion cientifica y conservacion dependeran, en gran medida, de la recuperacion de la estabilidad economica y politica del pais. EnglishA wide diversity of elasmobranch species has been reported for waters off Venezuela; however, information regarding this group is lacking for most coastal regions. This study aimed to determine the species composition in catches made by the artisanal fishery of Sucre State, Venezuela, and to analyze size structure by sex for the most common species. During the study period (January 2016–September 2017), visits were made to the main fish markets in the city of Cumana, Sucre State, and a total of 2,167 elasmobranchs belonging to 24 species (15 sharks and 9 rays) were quantified. The most frequently captured elasmobranch species were Mustelus higmani (36.2%), Mustelus canis (18.0%), Hypanus guttatus (15.1%), and Hypanus americanus (7.1%). The size ranges for these species were 29.3–73.7 cm total length (TL), 34.0–86.0 cm TL, 17.0–138.0 cm disc diameter (DD), and 48.0–108.0 cm DD, respectively. Considering national conservation assessments (following Inter","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44915553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diet composition and its relation to the characteristics of the digestive tract of the blue sea catfish, Ariopsis guatemalensis (Actinopterygii: Ariidae), in Barra de Navidad Lagoon, Jalisco, Mexico","authors":"Brenda Daniela Benítez Mondragón, Consuelo M. Aguilar Betancourt, G. G. Sansón, G. Ramírez, J. F. Ortega, S. Ramírez, Daniel Kosonoy Aceves","doi":"10.7773/cm.v45i4.3005","DOIUrl":"https://doi.org/10.7773/cm.v45i4.3005","url":null,"abstract":"espanolSe investigaron la composicion de la dieta y las caracteristicas del tracto digestivo del chihuil Ariopsis guatemalensis en una laguna costera en el oeste de Mexico. Esta especie es consumida por habitantes locales, y ha sido utilizada como bioindicadora de contaminacion por aguas negras. El objetivo de este estudio fue determinar si los habitos alimentarios de la especie estan relacionados con las caracteristicas morfologicas macroscopicas y microscopicas del tracto digestivo. Se capturaron los especimenes en la laguna Barra de Navidad ( Jalisco, Mexico) de 2011 a 2016. De cada individuo recolectado, se midio la longitud total (LT) y se extrajeron el esofago, el estomago y el intestino para el analisis histologico y la identificacion de las entidades alimentarias en su dieta. Segun las caracteristicas macroscopicas y microscopicas del tracto digestivo y el analisis del contenido estomacal, A. guatemalensis tiene habitos carnivoros y preferencia por los peces gobidos. Los crustaceos fueron la segunda entidad alimentaria mas importante, de los cuales destacaron los cangrejos portunidos y los camarones de fango. El tamano y la posicion de la boca, la presencia de placas dentarias en el vomer, los palatinos, los premaxilares y la faringe, y la presencia de celulas caliciformes en el tracto digestivo son caracteristicas de peces que ingieren presas vivas de consistencia dura y fraccionan su alimento antes de que este pase al esofago. El intestino relativamente corto y los pliegues en la mucosa son caracteristicas de peces carnivoros. EnglishDiet composition and the characteristics of the digestive tract of the blue sea catfish, Ariopsis guatemalensis , in a coastal lagoon in western Mexico were investigated. This species is consumed by locals and it has been used as a bioindicator of sewage pollution. This study aimed to determine if the feeding habits of this species were related to the macroscopic and microscopic morphological characteristics of the digestive tract. Specimens were captured in the Barra de Navidad Lagoon (Jalisco, Mexico) from 2011 to 2016. For every fish collected, total length (TL) was recorded and the esophagus, stomach, and intestine were extracted for histological analyses and identification of food items in their diet. The macroscopic and microscopic characteristics of the digestive tract and the stomach content analysis indicate A. guatemalensis is a carnivorous species with preference for goby fish. Crustaceans were the second most important food item and were dominated by portunid crabs and mud shrimps. The size and position of the mouth, the presence of dental plates on the vomer, palatines, premaxilla, and pharynx, and the presence of goblet cells in the digestive tract are characteristic of fishes that consume live hard-bodied prey and crush their food before it enters the esophagus. The relatively short intestine and the folds in the mucous membrane are characteristic of carnivorous fishes","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":"45 1","pages":"151-162"},"PeriodicalIF":0.7,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45413416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Length–weight relationship and condition factor for 7 loliginid squid species in Mexican waters","authors":"J. G. Amores, C. A. S. Zavala, J. F. Ortega, Mariana Diaz Santana Iturrios","doi":"10.7773/cm.v45i4.3015","DOIUrl":"https://doi.org/10.7773/cm.v45i4.3015","url":null,"abstract":"espanolLa relacion longitud-peso y el factor de condicion son parametros primarios en la evaluacion de poblaciones pesqueras. A pesar del potencial pesquero de los calamares loliginidos en Mexico, el grupo es escasamente conocido y no hay un manejo formal implementado. Un total de 1,105 calamares capturados en aguas mexicanas del Pacifico y del Atlantico fueron medidos para estimar la relacion longitud-peso y los factores de condicion. Excepto Lolliguncula brevis y Lolliguncula argus, todas las especies presentaron crecimiento alometrico negativo. Las 2 especies con crecimiento isometrico presentaron una condicion pobre, segun el factor de condicion de Fulton, y el resto de las especies presentaron buena condicion de salud, segun el factor de condicion relativo. El tipo de crecimiento encontrado en las especies identificadas en este estudio puede estar relacionado con sus habitos de nado o, de otra manera, puede ser afectado por las mismas variables que determinan el tipo de crecimiento de otros calamares encontrados en aguas mexicanas. Los parametros evaluados en esta investigacion ahora se encuentran disponibles para ser incorporados en futuros modelos de manejo de poblaciones pesqueras de calamares loliginidos. EnglishThe length–weight relationship and the condition factor are key parameters in stock assessment. Despite the fisheries potential loliginid squids have in Mexico, the group is scarcely known and no formal management has been implemented. A total of 1,105 squids captured on the Pacific and Atlantic coasts of Mexico were measured to estimate length–weight relations and condition factors. Except for Lolliguncula brevis and Lolliguncula argus, all species showed negative allometric growth. The 2 species with isometric growth showed a poor condition, according to Fulton’s condition factor, and the rest of the species were in good health, according to the relative condition factor. The type of growth exhibited by the species identified in this study could be associated with their swimming habits or otherwise be affected by the same variables that determine the type of growth of other squid found in Mexican waters. The parameters evaluated in this research are now available for incorporation in further fishery stock assessment models for loliginid squids.","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":"45 1","pages":"175-180"},"PeriodicalIF":0.7,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43129952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fine-scale site fidelity in California sea lions, Zalophus californianus , in the colony at Los Islotes, La Paz Bay, Mexico","authors":"A. Estrada, Claudia Hernández Camacho","doi":"10.7773/cm.v45i4.3019","DOIUrl":"https://doi.org/10.7773/cm.v45i4.3019","url":null,"abstract":"espanolDentro de los pinnipedos poliginicos, la fidelidad al sitio a escala fina influye en las interacciones individuales, la estabilidad social y el flujo genetico; con el tiempo, puede afectar procesos demograficos e, incluso, llevar a la extincion local de algunas colonias. El objetivo de este trabajo fue estimar el grado de fidelidad al sitio a escala fina para hembras adultas de lobo marino de California, Zalophus californianus , en 3 areas de reproduccion y su relacion con su exito reproductivo en la colonia reproductiva Los Islotes, bahia de La Paz, Baja California Sur, Mexico. Se estimo el indice de fidelidad al sitio a escala fina individual y la tasa de retorno a partir de la historia reproductiva de 5 cohortes de hembras marcadas desde crias entre 1980 y 1984. Se utilizo una correlacion de Pearson para ver si existia una relacion entre la fidelidad al sitio y el exito reproductivo (numero de crias que tuvo una hembra durante el periodo de estudio) de cada individuo durante el periodo de estudio de 9 anos, y se comparo el exito reproductivo entre sitios mediante una prueba de chi cuadrado. Las hembras adultas de lobo marino de California mostraron alta fidelidad a la colonia, la mayoria con valores de fidelidad al sitio por encima del 40%; el sitio A y el sitio B mostraron la mayor tasa de retorno, mientras que el sitio C fue el de menor preferencia. No hubo diferencia significativa en la relacion entre la fidelidad al sitio a escala fina y el exito reproductivo, ni tampoco en el exito reproductivo entre sitios. La elevada fidelidad al sitio a escala fina aparentemente no ha tenido efectos negativos en esta colonia, como lo indica el aumento significativo de la poblacion en las ultimas 3 decadas y sus tasas reproductivas relativamente altas. EnglishFine-scale site fidelity in polygynous pinnipeds influences individual interactions, social stability, and gene flow; over time, demographic processes may be altered, and local extinction of some colonies may occur. The goal of this study was to evaluate fine-scale site fidelity as it relates to reproductive success of California sea lion, Zalophus californianus , adult females at 3 different reproductive sites in the Los Islotes rookery in La Paz Bay, Baja California Sur, Mexico. Reproductive history data for 5 cohorts of California sea lions marked as pups between 1980 and 1984 were used to estimate the individual fine -scale site fidelity index and the return rate. A Pearson correlation was used to evaluate whether there was a relationship between site fidelity and reproductive success (number of pups that a female had during the study period) during the 9-yr study period, and a chi-square test was used to compare reproductive success between sites. Adult female California sea lions showed high site fidelity to the colony, with the majorit y showing site fidelity values &gt;40%; sites A and B had high return rates, whereas site C was the least preferred. There was no significant difference i","PeriodicalId":50702,"journal":{"name":"Ciencias Marinas","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49477106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}