Environmental Changes 1

There are many large-mouth bass, a type of fish, living in a small lake near Waco, Texas. How would increased fishing in the lake effect the lake ecosystem?

• The predators of the large-mouth bass might starve due to loss of food source

• The predator of the large-mouth bass population would increase.

• Bass would spend more time swimming near the surface

• Water in the lake would decrease due to more fishing in the lake

Prairie dogs eat plants and dig underground tunnels. Prairie dog tunnels help break up hard prairie soils, and the animals' waste adds nutrients to the soil. In the past, large groups of prairie dogs lived in many parts of the U.S. Great Plains, but people have destroyed most of these colonies. Which of these will most likely happen when prairie dogs are removed from an area?

• The population of predators that eat prairie dogs will decrease.

• The population of plants that prairie dogs eat will decrease.

• The nutrients in the soil will increase.

• The number of underground tunnels will increase.

Wild Texas hogs, similar to the one shown here, are descended from hogs brought here from other countries. These wild hogs eat many different kinds of foods, including plants, fungi, and insects. Besides being very destructive to the habitats of other animals, how do wild hogs most likely harm other animals?

• By competing with other animals for food

• By moving slower than most other animals

• By causing other animals to reproduce more

• By eating foods that no other animals eat

This picture shows a type of plant called kudzu. Kudzu is a fast-growing Asian vine that was introdued into the United States. Kudzu quickly uses available resources and can completely cover the plants in an area. What effect does the rapid growth of kudzu most likely have on an ecosystem?

• The variety of native plants decreases.

• The water supply in the area increases.

• Weather patterns in the area change.

• The number of other plants increases.

Humans are part of the ecosystems of the Earth and therefore impact it. Which of the following events in an ecosystem may produce a negative effect?

• Preventing deer from depleting food resources

• Restoring a natural habitat

• Recycling and using biodegradable products

• Clearing a forest to build homes