Knowledge about the population structure of freshwater eels and their habitats is crucial for conservation and exploitation purposes, but this information is lacking for Kenyan anguillid eels, thus there was need to carry out the current study. A total of 304 eels were landed between May 2021 and June 2022, with the longer eels occurring in the River AGS compared to those of the River Ramisi, (t-test ; P <0.01). The study revealed a significant contrast among species populations between the rivers (p<0.05), with the highest relative abundance occurring in size class 50-60 cm (36%). Size class >80cm had the heaviest eels with River AGS having heavier eels than Ramisi. River Ramisi had a higher Catch Per Unit Effort (CPUE) in all the eel growth stages than the River AGS. Biotopes of River Ramisi comprised a higher number of eels (61.6%) than those of the River AGS (38.4%). The study confirmed that Kenyan rivers consist of freshwater eels of different size classes that prefer different biotopes.

Keywords: Anguilla eels, River AGS, River Ramisi, Abundance, Size class, Habitat preference