Using a magnifier, mini marine biologists examine the barbules of a bird feather. They swirl the it into a mixture of oil and water and then re-examine the feather. After the activity, discuss how the oily feathers pose a problem to sea birds during an oil spill and how an ocean food web may be impacted by such an occurrence. This lesson plan is brief, but to the point. It can be used in conjunction with other lessons about human impact on the environment.