Why are monarch butterflies disappearing? Scientists are racing to find answers. These iconic orange, black, and white butterflies flutter across much of the North American continent, and are a familiar summer sight in many backyards. But in the last twenty years, the monarch butterfly population has been decreasing. Why? Skilled science writer Rebecca E. Hirsch takes readers on a quest to discover what scientists already know--and what they're hoping to learn. In addition, she offers tips about what monarch lovers can do to make a difference, from planting a butterfly garden to getting the word out about harmful pesticides to taking part in citizen science projects.