Abstract :
The physicochemical flux, composition and abundance of crustacean larvae in two mesohaline creeks of Lagos Lagoon were investigated. The status of the Physico-chemical parameters indicates a non-significant difference between variables except Alkalinity with Abule-Eledu Creek having significantly higher mean value (144.4±2.2 mg/L) than Abule-Agege Creek (121.9±4.9 mg/L). The transparency values of the creeks increased with a reduction in the amount of rainfall while the water temperature as well as salinity values increased appreciably with the dry season. An increase in conductivity (>190.40 ?S/cm) and salinity (>10.50‰) in the dry months for both creeks was also observed. The crustacean larvae were represented by five orders with Calanoida and Cyclopoida (Sub-Class: Copepoda) were the most frequent and notable orders occurring in Abule-Eledu and Abule-Agege creeks respectively. Other crustacean categories such as Mysida, Calanoida and Harpaticoida were also recorded. Total species diversity was14 in Abule-Eledu creek and 17 in Abule-Agege Creek. Shannon-Wiener Index values ranged between 0.90 and 0.96 for Abule-Eledu Creek and between 0.97 and 1.09 for Abule-Agege Creek. With the exception of Menhinick Index and Equitability Index, all other biotic indices were higher in Abule-Agege Creek than Abule-Eledu creek. This study therefore suggests that Calanoida and Cyclopoida which are orders of the subclass Copepoda are the dominant crustacean zooplankton group in the creeks of the Lagos Lagoon
Keyword :
Crustacean; Water chemistry; Larvae; Abule-Agege Creek; Abule-Eledu Creek