Shafagh Kamal; Asghara Abdoli; Majid Bakhtiary; Mahmoud Karami
Volume 6, Issue 3 , April 2009
Abstract
Some biological traits of Killifish (Aphanius sophiae)of CheshmeAli Damghan such as age and growth frequencies, condition factor, von Bertalanfy growth parameter, Gonadosomatic index, fecundity and egg diameter were studied monthly from October 2004 to November 2005. During the study 535 specimens were ...
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Some biological traits of Killifish (Aphanius sophiae)of CheshmeAli Damghan such as age and growth frequencies, condition factor, von Bertalanfy growth parameter, Gonadosomatic index, fecundity and egg diameter were studied monthly from October 2004 to November 2005. During the study 535 specimens were sampled with a net which bears a mesh size of 1mm. Sex ratio of Cheshme Ali population was 1 :♂ 1.367♀.There was significant difference between male and female (χ2=12.877, p=0.000)). Length and age frequency studies showed that female fishes were longer and older than male fishes. Male fishes had higher condition factor than females (F=40.037, p=0.000). Reproduction cycles of these fishes were estimated to be about 6 month and the peak of GonadoSomatic Index of females was in May. Eggs diameters were from 0.53 to 2.73 mm.
Gholam Reza Banagar; Mahmoud Karami; Bahram Kiabi; Mahmoud Ghasempouri
Volume 6, Issue 2 , January 2009
Abstract
Fish diversity of Haraz River Was Studied from November 1999 To August 2000. This river is situated in The Southern Caspian basin of Iranian Mazandaran Province. Five Stations Were Selected along The River. 522 specimens were Collected and studied, that belonged to 20 species and 9 families: Petromyzontidae, ...
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Fish diversity of Haraz River Was Studied from November 1999 To August 2000. This river is situated in The Southern Caspian basin of Iranian Mazandaran Province. Five Stations Were Selected along The River. 522 specimens were Collected and studied, that belonged to 20 species and 9 families: Petromyzontidae, Cyprinidae, Cobitidae, Salmonidae, Gobiidae, Mugilidae,Balitoridae,Poeciliidae and Gasterosteidae.Cyprinids comprised 67.2 percent of the species. Seventy percent of species were resident and 30 percent anadromous. Rain bow trout (Oncorhynchus mykiss), Gold fish (Carassius auratus), (Liza saliens) and Stickle back (Gasterosteus aculeatus) and Gambusia (Gambusia holbrooki) were introduced species. Shannon- Wiener's coefficient of diversity (H'), Food selectivity and Horn's coefficient of niche overlap were estimated.
Roohallah Mirzaei; Mahmud Krami; Afshin Danehkar; Asghar Abdoli
Volume 6, Issue 2 , January 2009
Abstract
The Eurasian otter (Lutra lutra) is a semi-aquatic mammal from Mustelidae family. It is recognized as one of the top predators in freshwater systems, and thus has the potential to play an important role in the functioning of these systems. There are only 2 otter species in Iran .Information about this ...
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The Eurasian otter (Lutra lutra) is a semi-aquatic mammal from Mustelidae family. It is recognized as one of the top predators in freshwater systems, and thus has the potential to play an important role in the functioning of these systems. There are only 2 otter species in Iran .Information about this species in Iran is absent. River ecosystems are one of the important habitats for otters. Jajrood River with 140 km length in the east of Tehran is one of these habitats that were selected for this study. To study otter distribution standard method was used. This method is a systematic sample survey for field signs of otters. 16 survey sites at about 5 km intervals were selected and Otter signs, habitat parameters such as vegetation cover, river width and fish of river were recorded for each 600m stretch by walking the entire it (both banks) of all river, wading in the river wherever possible. A total of 599 signs (spraints, tracks, holst,rolling places and passes) were identified over the whole study period, the most common being spraints. Otter spraints were found in 6 of the sites of river Surveyed and in the study area, three core areas could be identified.
