How did tilapia change lake Victoria ?

The second option and/or third option is correct.

Explanation:

I did a case study on the addition of Tilapia to Lake Victoria with OneWorld.

The effects are listed in our publication.

"In efforts to improve food production and bolster the fish-export business in Eastern Africa, the Tilapia was introduced to Lake Victoria, the largest tropical lake in the world, which serves as the main source of sustenance for the people of Kenya, Tanzania, and Uganda. Instead of improving the fishing opportunities in the lake, however, the Tilapia has caused the decimation of several fish populations.

Tilapia’s aggressive and omnivorous feeding behavior outcompeted native species or utilized native species themselves as a food source. Indigenous cichlids play a major role in reducing detritus, but with severely decreased numbers, their ability to consume this organic material is diminished. As the detritus decays and sinks to the lake floor, it absorbs oxygen. The decimated cichlid population led to unprecedented amounts of detritus, which has depleted oxygen at the lowest levels of the lake and created dead zones. Lake Victoria, considered one of the most species-diverse lakes in the world, has seen its cichlid population drop from 400 to 200 species due to the introduction of the Tilapia and other invasive species, such as the Nile Perch."