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Weight-length relationships are reported for 38 species of teleost fish belonging to 20 families. Data were collected on a regular basis from February 2011 to January 2012 in the Barra de Navidad coastal lagoon, Jalisco, Mexico. Several different types of sampling gear were used to obtain a broad range of fish lengths. These are the first records in FishBase regarding weight-lengths for eight of the species. U.S.

RESUMEN. La lisaMugil curema tiene amplia distribución en América, habitando sistemas costeros y estuarinos. Es un recurso con importancia pesquera en varias regiones del Pacífico mexicano. El objetivo del presente trabajo es describir aspectos reproductivos de M. curema durante un ciclo anual. Se realizaron muestreos mensuales con redes y atarraya de febrero 2011 a enero 2012 en la Laguna Barra de Navidad, Jalisco, México. Se analizaron 495 ejemplares, a los cuales se les midió la longitud y el peso total. De cada ejemplar se extrajeron las gónadas, se pesaron, clasificaron según su maduración y se procesaron para histología. Se capturaron ejemplares entre 10,3 y 38,5 cm, con promedio de 26,1 cm. Se identificaron 375 hembras con promedio de 27,2 cm y 110 machos con promedio de 23,4 cm. El número de hembras dominó de manera significativa en la muestra total, por mes y por clase de longitud. Los valores máximos del índice gonadosomático ocurrieron en abril, agosto y noviembre. El factor de condición presentó valores altos en varios meses coincidiendo en ambos sexos. En la ovogénesis se identificaron seis fases de desarrollo de los ovocitos y debido a la gran cantidad de ovocitos con crecimiento primario y en vitelogénesis 2 y 3, el patrón de desarrollo fue sincrónico por grupos con desove total. La longitud promedio de madurez (L50) de machos fue de 21,7 cm y de hembras de 24,5 cm. Contrastando estas dos últimas longitudes con las de captura, se sugiere que más del 50% de los organismos capturados son individuos que se reprodujeron al menos una vez. Palabras clave: Mugil curema, lisa, índice gonadosomático, histología, madurez gonadal, México. Reproductive aspects of Mugil curema (Mugiliformes: Mugilidae) in the Barra deNavidad coastal lagoon, Jalisco, Mexico ABSTRACT. The white mullet Mugil curema is broadly distributed in America inhabiting coastal and estuarine systems. It is an economically important fishery resource in several regions of the Mexican Pacific. The goal of this research was the description of several reproductive aspects of Mugil curema during an annual cycle. Fish were sampled monthly with gill and cast nets from February 2011 to January 2012 in the coastal lagoon Barra de Navidad, Jalisco, Mexico. A total of 495 fish were analyzed. Total length and weight were measured for each specimen and gonads were collected, weighted, classified after their maturation stage and preserved for histological analyses. Caught fish were between 10.3 and 38.5 cm total length with a mean of 26.1 cm. A total of 375 individuals were classified as females with a mean total length of 27.2 cm while 110 fish were classified as males with a mean total length of 23.4 cm. Females dominated by numbers in the total sample, monthly and by length classes. Highest values of the gonadosomatic index occurred in April, August and November. Condition factor showed high values in several months and its trend along the year was similar in both sexes. Six stages were identified during the oogenesis and, due to the high quantity of p...

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The main goal of this research was to investigate the differences in diet composition among three species of the genus Lutjanus inhabiting a coastal lagoon as juveniles. The working hypothesis was that these species feed on a common base of food resources and therefore, some niche overlap is present in terms of general diet composition. However, changes in the trophic niche with size and differences in some morphological traits among species explain observed differences in diet. Fish were collected during 42 sampling trips conducted regularly from February 2011 to January 2012 using several types of fishing gear. Total number of analyzed stomachs was 288 for Lutjanus argentiventris from 2.3 to 19.9 cm total length (TL); 178 for Lutjanus colorado ranging from 2.4 to 30.1 cm TL; and 183 for Lutjanus novemfasciatus with 1.2 to 20.0 cm TL. Results indicate that juveniles of all three lutjanid species share a general diet based on decapods and fishes. However, L. novemfasciatus has a more piscivorous habit, which can be explained by a more slender body shape and larger teeth, characteristics, which increase fish catching performance. Larger fish of all three species eat larger prey, which is consistent with the optimum foraging theory.