A twenty-four (24) week investigation was carried out in River Donga, to determine the shellfish species abundance and diversity. The section of the River was sampled and human activities were considered in the choice of sampling stations. A total of five (5) individual species of shellfish were identified; they comprise of five (5) families, five (5) genera and three (3) orders; including one (1) terrestrial (land) snail (Anixa zebuensis); the highest caught individual species was H. pomatia (1,072) species, while the least caught individual species was C. obeyensis (1) species. A total of 1,305 species of shellfish were caught. Analysis of variance (ANOVA) was used to test for the significant difference occurring in various physicochemical parameters between stations. Pearson’s Correlation was used to test the relationship between physicochemical parameters and shellfish composition of the river at P<0.01 significant level. The highest temperature value (27.11±0.05b) was recorded in station B; the least value (26.98±0.03a) was recorded in station A. The mean pH values were slightly acidic; the highest pH value (6.57±0.08a) was recorded in station A and the least value (6.29±0.1b) was recorded in station C. The highest Dissolve Oxygen value (6.06±0.03b) was recorded in station C and the least value (5.94 ±0.05a) was recorded in station B. Electrical Conductivity, the highest value (16.05±0.03b) was recorded in Station C and the least value (15.85±0.02a) was recorded in station B. The highest turbidity value (34.32±0.15b) was recorded in station C; the least value (33.95±0.03a) was recorded in station B. The highest total dissolved solid value (0.29±0.01a) was recorded in station B; the least (0.26±0.01a) was recorded in station A. The river was described as slightly productive in terms of its shellfish richness. It was recommended that the physicochemical characteristics of the researched ecosystem is adequate for species survival. Nevertheless, it is paramount that the monitoring of human activities and the conservation of its natural resources are considered to aid sustainable diversity for food sovereignty and security to better the lives of the aquatic species in the ecosystem amidst anthropogenic activities and climate change.