International Journal of Current Microbiology and Applied Sciences
ISSN: 2319-7706 Volume 2 Number 10 (2013) pp. 382-390
Sex population structure of Macrobrachium assamense peninsularie (Tiwari) (Crustacea, Decapoda, Palaemonidae) in Khoh River, Uttarakhand, India
Pankaj Bahuguna*
Fish Biology and limnology Laboratory,Department of Zoology, Govt. P. G. College Pithoragarh- 262502, Uttarakhand, Country - India
ABSTRACT
The prawns were collected from spring fed Khoh River for a period of one year during April 2010 to March 2011. The river and all its tributaries contain swiftly flowing water. The nets used for prawn fishing, were (1) Depnet and (2) Fatella. The prawn was preserved in 5% formalin for further study. The dead prawns were examined and identified using a stereoscopic microscope. Macrobrachium species were identified. The total length and weight of prawn was recorded in fresh condition. However, the other parameters were measured within a fortnight of collection. A total of 242 specimens were collected (134 males and 108 females). During the present observation, the size of the prawn Macrobrachium assamense peninsularie (Tiwari), reached a maximum total length of 62 mm for male and 67 mm for female. The minimum size recorded was 29mm for male and 32mm for female. Thus, a minimum length of 29mm and maximum length of 67mm of the prawn fish was recorded respectively. The seasonal and pooled data indicated variations in the sex composition of Macrobrachium assamense peninsularie are presented in the table 2. The sex population observed season wise, varied from a maximum in winter season (2.25male:1.005female) and minimum in summer season (1.05male:1.00female). The total pooled data showed an average sex population status of 1.24male:1.00female Macrobrachium assamense peninsularie during the course of study. The estimation of sex population both in male and female showed non-significantly at 5% level of non-significance in the months, season and in the pooled data. In the month of February and autumn season there were significant differences in the ratio of male and female fish (For February: 2.57male:1.00female; For autumn season: 2.25male:1.00female)
Keywords
Prawns; Khoh River; Macrobrachium species; Macrobrachium assamense peninsularie sex population