Problem Solving & Endangered Species

How do scientists determine the best way to solve important problems?

1. Himalayan blackberry is an invasive plant species that tends to choke out other plants wherever it grows. Scientists want to determine a way to remove blackberry from forest ecosystems without harming other plants. Describe how to begin solving this problem. Be sure to describe the following stages in your design process:

Explore Ideas:

• Are there chemicals that kill blackberry but not other plants? Try different chemicals on them.

• Are there animals that eat blackberry plants but not the plants they grow on? Go out and observe. Look up on internet.

• Research the Problem: Describe any scientific information needed to solve the problem and how to collect that information.

• Explore Ideas: Describe several possible solutions to the problem, including any useful scientific concepts.

Research the Problem:

• Spray them with weed killer. • Bring in animals that eat blackberry.

2. Describe two scientific reasons to support developing laws for the protection of species like salmon. In your description, be sure to• Identify two reasons to support developing laws for the

protection of species like salmon.• Justify each reason with a different scientific idea.

One reason:

Another reason:

Salmon eat a lot of other animals. Without salmon, those other animals would overpopulate.

Salmon are eaten by other animals. Without salmon those other animals would starve.

3. Scientists have been investigating changes in the populations of Chinook salmon. The Chinook Salmon Population graph below shows the changes in Chinook salmon populations in the Salish River over a 26-year time span.

• Describe two conditions in the ecosystem that could cause the trend in the Chinook Salmon Population graph. In your description, be sure to:

• Identify two conditions in the ecosystem that could cause the change in salmon population. • Describe how each condition in the ecosystem would affect the salmon population.

One condition:

Another condition:

Increase in predators. Got eaten.Decrease in food. Died of starvation.

Pollution. Killed by chemicals.

Field studies are scientific investigations done outside when you want to see how things behave in their natural environment. In contrast, controlled experiments are done inside when you want to see how things behave in a small, controlled environment like a laboratory.

How would it be different studying plants outside in their natural environment, compared to studying them in an enclosed building?

4. Wildlife biologists want to determine the effect of decreasing spotted owl populations on the Pacific Northwest forest ecosystem.

• Describe one reason why a field study is the appropriate type of investigation to determine the effect of decreasing owls.

• Describe one way scientists can ensure the validity of this field study.

If want to study effects of decreasing owl populations on forest ecosystem, have to go outside and study ecosystem. Can’t do inside.

• Don’t just do for one year; study for several years.

• Choose several areas to study, not just one.