Which of the following is an example of alien species invading a new ecosystem resulting in biodiversity losses ?

Options

A. Introduction of Nile Perch into lake Victoria in east Africa
B. Introduction of Water Hyacinth into India
C. Introduction of African Catfish into Indian waters
D. All the above.

Answer

To determine which of the following is an example of alien species invading a new ecosystem resulting in biodiversity losses, we will analyze each option provided:

1. **Introduction of Nile perch into Lake Victoria in East Africa**:
- The Nile perch was introduced into Lake Victoria, which led to the extinction of over 200 species of native cichlid fish. This introduction significantly disrupted the local ecosystem and resulted in a loss of biodiversity.

2. **Introduction of water hyacinth into India**:
- Water hyacinth (Eichhornia crassipes) is an invasive aquatic plant that has caused severe environmental damage in India. It competes with native aquatic plants, leading to declines in biodiversity and disrupting local ecosystems.

3. **Introduction of African catfish into Indian waters**:
- The African catfish was introduced into Indian waters for aquaculture. This species poses a threat to native catfish species, leading to declines in their populations and thus impacting biodiversity.

4. **All of the above**:
- Since all the previous examples (Nile perch, water hyacinth, and African catfish) represent cases where alien species have invaded new ecosystems and caused biodiversity losses, this option is also valid.

**Conclusion**: The correct answer is **all of the above (option 4)**, as each example illustrates the negative impact of alien species on biodiversity.