«Llambina» Potamorhina altamazonica is the second dominant species in the commercial fishery landings in the Ucayali region and of great importance in the regional socio-economics. The aim of this study was to determine the reproductive characteristics of this species. Spawning period, sex ratio, average size at maturity and condition factor were analyzed. The analysis showed that the spawning have synchrony with the increase of water level in the Ucayali river in the transition to high water and in the high water seasons, starting in October, with intense spawning between January and February and completion in March. The sex ratio was significantly favorable to females at most times of the year. The average size at first sexual maturity was estimated at 17.8 cm in females and 18.4 cm in males (total length). The fish showed better somatic condition in the dry season (July to October),...

The aim of this study was to determine the population structure, sex ratio, reproductive condition, population index and biomass of Cryphiops caementarius in the Cañete (Lima), Tambo, Ocoña and Majes (Arequipa) rivers, Peru. The research was carried out based on information obtained by the Instituto del Mar del Perú. The biologicalpopulation analysis was carried out from prawn samples obtained by systematic captures in different altitude strata. The water quality parameters presented values that were within the acceptable ranges for the normal development of the resource. The modal sizes of the resource were less than 70 mm (minimum catch size) in the Cañete, Tambo and Majes rivers. A higher proportion of males was determined in the Cañete, Tambo and Ocoña rivers, and a lower proportion in the Majes river. The proportion of spawning females was less than 10% in the evaluated months...

«Llambina» Potamorhina altamazonica is the second dominant species in the commercial fishery landings in the Ucayali region and of great importance in the regional socio-economics. The aim of this study was to determine the reproductive characteristics of this species. Spawning period, sex ratio, average size at maturity and condition factor were analyzed. The analysis showed that the spawning have synchrony with the increase of water level in the Ucayali river in the transition to high water and in the high water seasons, starting in October, with intense spawning between January and February and completion in March. The sex ratio was significantly favorable to females at most times of the year. The average size at first sexual maturity was estimated at 17.8 cm in females and 18.4 cm in males (total length). The fish showed better somatic condition in the dry season (July to October),...

El pejerrey Odontesthes bonariensis es el segundo recurso pesquero más abundante en el lago Titicaca, por ello viene soportando intensa actividad extractiva. Ante su importancia socioeconómica y alimenticia, se ha realizado el estudio con información biológica correspondiente al periodo 2009 – 2015, en cuatros zonas del lago Titicaca (Bahía Puno, Zona Norte, Zona Sur y Lago Pequeño) con el fin de conocer los variaciones temporales de los parámetros biológicos tales como el índice gonadosomático (IGS), índice de actividad reproductiva (IR), factor de condición (FC), talla de primera madurez sexual, parámetros de la estructura poblacional por tallas y los parámetros de edad y crecimiento. El periodo de desove tuvo la amplitud de cuatro a seis meses, ocurriendo principalmente en el invierno. El comportamiento térmico de la laguna influye sobre el desove del recurso, se obse...

Tesis (Magister en Ecosistemas y Recursos Acuáticos) .- Universidad Nacional Mayor de San Marcos. Facultad de Ciencias Biológicas. Escuela de Post Grado.

«Chiochio» (Psectrogaster rutiloides) is one of the 10 representative species in the catches of the commercial fleet of Pucallpa, Peru. The aim of this study was to generate information for the understanding of its biology and fishery. Reproductive aspects (time of reproduction, size at maturity [TPM], sex ratio), relationship Length-Weight, growth and rate of exploitation were studied in chiochio landed in Pucallpa ports between 2008 and 2012. Data of length frequency distribution were used to estimate the proportion of individuals below the estimated landed TPM. Also, information from 2011 was used to determine the growth parameters (Loe, K and t0), natural mortality (M) for fishing (F) and total (Z), and estimate the exploitation rate (E). The results showed that «chiochio» spawns during the transition to increasing, and reaches the TPM at 1 year of age with 12.2 cm total length (...

El chiochio (Psectrogaster rutiloides) es una las 10 especies más representativas en la pesca de la flota comercial de Pucallpa, Perú. Esta investigación tuvo el objetivo de generar información para la comprensión de su biología y pesquería. Se estudiaron los aspectos reproductivos (época de reproducción, talla de primera madurez [TPM], proporción sexual), relación Longitud-Peso, crecimiento y tasa de explotación del chiochio desembarcado en puertos de Pucallpa entre 2008 y 2012. Datos de distribución de frecuencia de tallas fueron utilizados para estimar la proporción de ejemplares desembarcados inferior a la TPM estimada. La información de 2011 fue utilizada para determinar los parámetros de crecimiento de la especie (Loe, K y t0), mortalidad natural (M) por pesca (F) y total (Z), y estimar la tasa de explotación (E). Los resultados indican que la especie desova durant...