Assessment of the physico-chemical parameters and prawn species in Ase River, Delta State, Nigeria

Abstract

The study was conducted to determine the physico-chemical parameters and prawn species available in Ase River at Ndokwa East L.G.A.  of Delta State, Nigeria. Water samples were collected for nine (9) months from January to September, 2023. Samples were collected with  plastic bottles at the deepest part of the river, they were labelled and kept in ice-chest box and transported to the laboratory for further  analysis. Analysis of the water parameters followed standard procedure. Dissolved oxygen, electrical conductivity, temperature and pH  were measured in-situ while other variables: (total dissolved solid, nitrate, carbonate, biochemical oxygen demand, and hardness) were  determined in the laboratory. Prawn samples were collected from artisanal fisherfolks who used traditional basket valve traps made of  bamboo to harvest. All protocol followed standard procedure. Results showed the mean dry season water temperature (27.9 ± 0.22 mg/l),  carbonate (1.02 ± 0.02 mg/l) and BOD (2.23 ± 0.05 mg/l) which were significantly different (p < 0.05) and higher than the mean results  for the wet season which were 26.6 ± 0.03 mg/, 0.86 ± 0.05 mg/l and 1.79 ± 0.10mg/l for temperature, carbonate and BOD respectively.  Prawn species obtained and their percentage prevalence were Macrobrachium vollenhovenii (41.8%), Macrobrachium macrobrachion (36.5%) and Macrobrachium potamalpheops (21.7%). Results from the study showed that the variation in physico-chemical parameters  influenced the abundance of prawn species found in the environment. It is recommended that government agencies carry out fisheries  extension education which could help the artisanal fisherfolks in sustainable harvest practices.