Title: The Recruitment Pattern of Liza falcipinnis from Elechi Creek, Upper Bonny, Niger Delta, Nigeria
Abstract: The Recruitment Pattern of Liza falcipinnis from Elechi creek of Upper Bonny, Niger Delta, Nigeria was studied from (March 2009-January 2010).The pattern showed all year round recruitment with two peaks (one major and one minor) during the period of the study.The parameters obtained were L ∞ = 19.96,K = 0.40 y -1 , C = 0, WP = 0, t o = 0.The C indicates the amplitude of seasonal growth oscillations (that is, the magnitude of the growth patterns) and has values ranging from 0 to 1.0.Winter Point (WP) indicates the times of the year during which growth is minimal.The percentage recruitment for the different months were: March 2009 (15.0%);April (23.40%);May (14.0%);June (11.3%);July (10.0%);August (7.30%);September (1.8%); October (0.5%); November (2.2%); December (8.0%) and January 2010 (6.0%).The exploitation rate (E max ) that gives maximum relative yield-per-recruit was 0.424.The exploitation rate at which marginal increase occurred in the relative yield-per-yield was 10% of its value at E = 0, whereas (E 0.1 ) was observed to be 0.357.The exploitation rate (E 0.5 ) which corresponds to 50% of the virgin (that is, the unexploited stock) relative biomass-per-recruit was estimated to be 0.279.The mean ratio of length-at-first capture (L ∞ ) and asymptotic length (L ∞ ) was 0.060, while that of natural mortality (yr -1 ) and growth rate (yr -1 ) was 1.00.Yield per increased gradually with increase in exploitation and Biomass per recruit declined with increase in exploitation.An all year round recruitment, with one high pulse arid a low pulse was established for the species.Research should be carried out to ascertain the influence of environmental factors on the growth and recruitment of the species.