Abstract

The abundance of Pellonula leonensis in relation to location, photoperiod, depth, tide, season and gill net selectivity was studied from May 2001 to April, 2002 in the Lower Nun River, Niger Delta. Three sets of gill net with stretched mesh sizes of 8, 12 and 15 mm respectively were used each measuring 35 m in length and 3 m in depth having a surface area of 105 m². Abundance was least in September and highest in February andP. leonensis was more dominant in the convex area of the river and lowest in the concave section. There was no significant variation (P > 0.05) in abundance of P. leonensis with photoperiod, water depth, tide and season. There was gillnet selectivity with the medium mesh size (12 mm) gill net as more effective constituting 68.77% of the total catch of P. leonensis in the Lower Nun River.

Key words: Abundance, gill net selectivity, Pellonula leonensis, Lower Nun River, Niger Delta.