Question

Sample Response: The population of unionid mussels in the Hudson River decreased after zebra mussels were introduced. Zebra mussels, a nonnative species, competed with the unionid mussels for food. The zebra mussels were able to outcompete the unionid mussels, allowing the zebra mussel population to increase dramatically over six years. The unionid mussel population decreased due to a lack of food.

What did you include in your response? Check all that apply.

The population of unionid mussels in the Hudson River decreased after zebra mussels were introduced.
Zebra mussels competed with unionid mussels for food.
The zebra mussels were able to outcompete the unionid mussels.
The unionid mussel population decreased due to a lack of food.

Answer 1

Zebra mussels have caused significant damage to North American waterways by outcompeting native mussels for food and altering ecosystems after being introduced via ballast water. They impact both the economy, by infesting water infrastructure, and the ecology, by changing species interactions and threatening the survival of native mussels.

Step-by-step explanation:

The introduction of zebra mussels (Dreissena polymorpha) to North American waterways is a prime example of the disruption invasive species can cause to native ecosystems. The zebra mussel was inadvertently introduced into the Great Lakes through ship ballast water from Europe. Since their introduction, they have caused significant economic impact by colonizing water intake structures and have altered the aquatic ecosystems by outcompeting native mussels for food, leading to a decline in native mussel populations, such as the unionid mussels in the Hudson River.

Zebra mussels, being efficient filter feeders, have increased water clarity in the Great Lakes, thereby changing the growing conditions for aquatic plants and affecting species interactions. While some species like the smallmouth bass may benefit from these changes, many native mollusks face a threat to their survival. Additionally, the spread and impact of zebra mussels are not limited to the Great Lakes; they continue to spread to other waterways, causing widespread ecological and economic damage.