Catch of the day. While this was the largest fish Matt caught, the Nile Perch can grow up to 1.8m/6ft and weigh up to 140 kg/310lbs. It is believed that Nile Perch numbers are on the decline as they have eaten most other species and are now starting to canalize their own population. Does this mean other species will again find their niche and make a comeback? An interesting question among ecologists.