Length-weight relationship and condition factor of shrimps in coastal waters of Ondo state, South West, Nigeria

Abstract

The Length-Weight Relationship (LWR) and condition factor (K) of Nematopalaemon hastatus, Farfantepenaeus notialis, Parapenaeopsis atlantica and Macrobrachium macrobrachion obtained from the coastal waters bordering Ayetoro, Bijimi, Asumogha and Idiogba of Ondo States, Nigeria between September and December, 2011 were studied. The length-weight relationship of the sampled shrimps had regression coefficient ranging between (b= 1.01) in M. macrobrachion caught in Bijimi in September to (b= 3.26) in P. atlantica caught in Bijimi in November. The b coefficients were not equal to 3 in the individual species, hence growth were allometric (b values were lesser/greater than 3). The highest condition factor (K = 0.57) and the lowest (K =0.48) in N. hastatus were recorded in December (at Ayetoro) and September (at Idiogba) respectively, while in P. atlantica, the lowest condition factor (K = 0.32) was recorded in September at Ayetoro, and the highest value (K = 0.52) was recorded in December at Bijimi. The months of September and October had the highest condition factor (K = 0.44) in F. notialis caught from Ayetorornlocation while the lowest K value of 0.31 was recorded in specimens caught at Idiogba in October. The range of K values which was from 0.46 (Bijimi in November) to 0.82 (Idiogba in October) in M. macrobrachion indicated that the shellfishes examined from four locations in Ondo State coastal area were in good and healthy conditions.