In a program called nature's notebook, citizen volunteers make and report observations about seasonal changes in plants and animals from year to year—such as flowering, emergence of insects, and migration of birds. this program is an example of

discovery science .

Explanation:

The discovery in ecology consists of making sustainable observations of creatures within their ecosystem. Though it consist of other things also like people,citizen etc. but the Nature's Notebook program fits the definition of discovery science.So we conclude that discovery science is the best choice for this question.