地理ジャーナルと自然災害
オープンアクセス

概要

Growth Patterns and Condition Factor of Hepsetus odoe (Bloch, 1794) Captured in Eleyele Lake, Southwest Nigeria

Kareem OK, Olanrewaju AN, Osho EF, Orisasona O and Akintunde MA

Hepsetus odoe is a commercially valuable fish and is considered as endemic to Nigeria. The growth patterns and condition factor of Hepsetus odoe from Lake Eleyele, Oyo State were investigated as an aspect of its biology essential for bringing it to culture. A Total of 205 specimens (55 and 150, males and females, respectively) were collected between June, 2012 and August, 2012. The morphometric indices such as Total Length (TL), Standard Length (SL), Body Weight (BW) and Stomach Weight (SW) were assessed using standard methods. Also, the length-weight relationship (W=aLb) and Condition factor (100W/L3) were calculated. Sex ratio of 1:3 (Males and Females) was obtained which shows a female dominated population. The Standard length (SL) and body weight (BW) ranged from 16.60-30.50 cm and 51.0-250.0 g respectively. Length-weight relationship equations were calculated as:

Log BW=2.051+3.105log SL (r=0.93)

This analysis showed significant relationship between the standard length, body weight and stomach weight. The relative condition factor (Kn) calculated ranged from 0.99-2.14 while the mean K value was 1.24. The condition factor fall within the range recommended for freshwater fish species in the tropics. The growth pattern indicates that the fish follows cube law and exhibited positive allometry growth. This information provides important tool in fishery management and guide for future culture trials.