Assignment

Active

Identifying and Describing Population Change

Organism

Number

per

square

meter

(1991)

Number

per

square

meter

(1994)

Number

per

square

meter

(1997)

Unionid mussels are native to the Hudson River in New

York State. In the early 1990s, zebra mussels were

introduced into the Hudson River. The table shows the

number of unionid mussels and zebra mussels over the

course of six years.

How did the population of unionid mussels change

after zebra mussels were introduced? Why did this

change occur?

Unionid

mussels

8

3

2

I

Zebra

mussels

4

1,329

3,181

Question

Mathematics

Spotty

7 July, 12:07

Assignment

Active

Identifying and Describing Population Change

Organism

Number

per

square

meter

(1991)

Number

per

square

meter

(1994)

Number

per

square

meter

(1997)

Unionid mussels are native to the Hudson River in New

York State. In the early 1990s, zebra mussels were

introduced into the Hudson River. The table shows the

number of unionid mussels and zebra mussels over the

course of six years.

How did the population of unionid mussels change

after zebra mussels were introduced? Why did this

change occur?

Unionid

mussels

8

3

2

I

Zebra

mussels

4

1,329

3,181

+3

Answers (1)

Know the Answer?

Davis Burgess · Answer 1

Answer: 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.