Abstract: This study was conducted in the southeastern part of the Caspian Sea in Mazandaran (Goharbaran) from a project [#4-76-12-95101] during 2013 -2014. Samples were collected monthly at 8 stations. The aim of this study was to evaluate the density and biomass of biological parameters at different months and their relationships with fish catch ratio such as Cyprinus carpio and Rutilus kutum Kamensky, 1901. Overall, 157 species of phytoplankton were identified which belonged to 8 phyla among them Bacillariophyta comprised to 48% of the highest species frequency. A total of 11 species of zooplankton, and 24 species of macrobenthos were found. There was a significant differences between density and biomass of biological parameters at different stations (p <0.05). The results showed that the density of phytoplankton in winter was the highest value at all stations. In contrast, the density of zooplankton decreased at the same time. This could be due to the lack of grazing animal e.g. zooplankton which grazing on phytoplankton. Based on Principal component analysis (PCA) the maximum value of similarity coefficient for C. carpio were in November and December (0.997) and for R. kutum Kamensky, 1901 in February and April (0.998), respectively. This could be due to the data of sampling stations which located to the inshore water and the substrate feeding behavior of carp and approaching the spawning season and spend the reproductive period in the river for Kutum.Abstract: This study was conducted in the southeastern part of the Caspian Sea in Mazandaran (Goharbaran) from a project [#4-76-12-95101] during 2013 -2014. Samples were collected monthly at 8 stations. The aim of this study was to evaluate the density and biomass of biological parameters at different months and their relationships with fish catch ratio such...Show More
Abstract: The present study, a total of 180 Luciobarbus capito was collected for growth and feeding characteristics 2016 at the Shahid Rajaei dam- Sari, Iran. Fish length to weight relationship was w= 0.0015*L2.888 showed negative allometric growth pattern. The Bertalanfy growth equation was as Lt = 138.6 [1-e-0.1 (t + 0.2)] in which L∞ =138.6 cm and k=0.1. Relative Length of Gut was 1.8 ± 0.5, which indicated the relatively herbivorous diet as a whole. Fishes -4 years old (sub-adult) with RLG= 2.4 ± 0.1 had herbivorous diet and with RLG= 1.2 ± 0.6 tended to omnivorous behavior. The results showed that this species had not specific nutrition, and generally fed on plant and macrophyta; meat diet included fish Carassius gibelio. According to the biological characteristics of this species, there is a high potential in inland waters and due to the suitable ecological conditions for this species, it was concluded that the use of strategies to protect the species in the Caspian Sea watershed and fisheries breeding and rearing should be a priority.Abstract: The present study, a total of 180 Luciobarbus capito was collected for growth and feeding characteristics 2016 at the Shahid Rajaei dam- Sari, Iran. Fish length to weight relationship was w= 0.0015*L2.888 showed negative allometric growth pattern. The Bertalanfy growth equation was as Lt = 138.6 [1-e-0.1 (t + 0.2)] in which L∞ =138.6 cm and k...Show More
