Population structure and growth characteristics of oriental river prawn, Macrobrachium nipponense (De Haan, 1849) in Soon Lun Reservoir, Mandalay Region, Myanmar

Investigation on the population structure and growth characteristics of freshwater oriental river prawn, Macrobrachium nipponense was conducted in Soon Lun Reservoir of Myingyan Township, Mandalay Region, Myanmar from June 2009 to May 2010. This study was aimed to investigate size frequency distribution, length-weight relationship and condition factor from study area. A total of 2207 specimens including 955 (56.73%) males and 1252 (43.27%) females were collected. It was observed that the numbers of females were significantly different (p< 0.05) from males. The differences in size group between sexes indicated a sexual dimorphism in M. nipponense. The medium size class of male total length (TL) was 51-80 mm and female TL was 41-65 mm predominated throughout the study period. The correlation coefficient of male (r = 0.947), non berried female (r = 0.801) and berried female (r = 0.912) were strongly positive related (p