Seasonal relative abundance of fish larvae in Helleh River estuary (north of the Persian Gulf, Iran)

Abstract

Abstract. Paighambari SY, Pouladi M, Parsa M, Mehdipour N, Haghighatjou N, Jabaleh A, Hedayati A. 2017. Seasonal relative abundance of fish larvae in Helleh River estuary (north of the Persian Gulf, Iran). Biodiversitas 18: 541-547. Study of abundance and composition of fish larvae in order to examine their association with salinity, temperature, dissolved oxygen and transparency was conducted in Helleh River estuary in the north of the Persian Gulf. Samples were collected using Bongo net with 500 μm mesh size and 60 cm mouth diameter size in five selected stations from August 2011 to May 2012. Generally, 1637 fish larvae were isolated from 19 families that most of them were belong to Clupeidae. Seasonal relative abundance (SRA) of fish larvae varied and Clupeidae (39.90%) and Gobiidae (14.35%) in summer; Clupeidae (26.23%) and Sparidae (21.82%) in autumn; Clupeidae (34.43%) and Hemiramphidae (12.02%) in winter; Clupeidae (47.93%) and Sparidae (13.67%) in spring were most abundant than others. Overall, families namely Clupeidae (39.28%), Gobiidae (12.58%) and Sparidae (10.57%) had the highest and Carangidae (0.92%) had the lowest relative abundance during the sampling period. ANOVA test also showed a significant difference between summer and autumn with spring and winter (P<0.05). According to CCA, in stations 4 and 5 in summer; stations 5 in autumn; stations 4 and 5 in winter; and stations 4 and 5 in spring with the highest relative abundance of fish larvae, salinity and temperature and partially transparency and in stations 2, 3 and 4 in autumn, stations 2 and 3 in spring, dissolved oxygen had significant correlation with fish larvae abundance in this estuary.

Short Communication: The presence of Bull shark Carcharhinus leucas (Elasmobranchii: Carcharhinidae) in the fresh waters of Sumatra, Indonesia

“…Osmoregulation in C. leucas is achieved through the control and integration of various organs such as the liver and kidney in response to salinity changes. However, little is known regarding the mechanisms of ion transport in the gills of euryhaline C. leucas and how they are affected by osmoregulatory challenges (Hazon et al 2003;Evans et al 2004) Estuaries are biologically diverse and productive ecosystems that provide essential habitats for many fauna and flora including avertebrata, finfish, reptile, and amphibian (Paighambari et al 2017;Abrantes et al 2019). Characterized by shallow water and intertidal areas, including mangrove forests, swamps, saltmarsh, seagrass, intertidal mudflats, and shallow sub-tidal habitats, they are transitional habitats between land and water and freshwater and marine environments (Thomas 2017;Dubuc et al 2019).…”