The Impact of Introduced Species on Lake Victoria's Ecosystem

1. Using a Key In which year was the number of cichlids the greatest?

a. 1950

b. 1970

c. 1990

d. 2010

2. Using a Key How many years did it take for the cichlid population to decrease by 50 percent?

a. 10 years

b. 20 years

c. 30 years

d. 40 years

3. Inferring Relationships Which fish in Lake Victoria do you think is higher on the food chain - the cichlid or the Nile Perch? Explain your answer.

4. Identifying Trends Based on the rate of decrease of cichlids shown on the map, what do you think will happen to the cichlid population by 2050? Explain your answer.

The introduction of the Nile Perch into Lake Victoria likely caused a decline in the population of cichlids as the new species acted as a predator. The Nile Perch is probably higher in the food chain, and if the current trend continues, the cichlid population may face a critical reduction or extinction by 2050.

Without the map, it's impossible to definitively answer your questions on the exact years or rate of decrease. However, I can provide some general insights. Typically, when a new species is introduced to an area, it can disrupt the local ecosystem. In this case, the introduction of the Nile Perch likely acted as a new predator for the cichlids, thereby causing their population to decrease.

From an ecological perspective, I believe it is reasonable to infer that the Nile Perch is higher up on the food chain than the cichlids given that their introduction caused a decline in the cichlid population. This is a typical consequence of introducing a new predator into an ecosystem.

Without the exact data from the map, it's challenging to predict the state of the cichlid population by 2050. If the trend of population decrease continues as a result of the introduced Nile Perch, it is possible that cichlids might face a critical reduction in their population or even extinction.