Genetic diversity of Nile tilapia (Oreochromis niloticus, L. 1758) in native and introduced populations in East Africa

Abstract

Freshwater fish in East African Lakes are under severe threat due to the recently discovered oil and gas in the Albertine Region and overfishing across the entire East African Region. The threats, primarily caused by overfishing, are a matter of declining fish populations and a potential reduction in genetic diversity in the surviving populations due to genetic drift. This study, therefore, is of utmost importance as it assessed genetic diversity in seven populations, including five from native and two from introduced populations. The assessment of genetic diversity in Oreochromis niloticus was conducted using molecular markers in 128 samples. The results showed a moderate genetic variation between native and introduced populations at mitochondrial and microsatellite loci. The potential effects of overfishing, fish introductions, and new threats from cage farming on the genetic diversity and ecological integrity of wildlife species are discussed, highlighting the need for immediate action.