As humans travel around the world, they sometimes introduce non-native species to new areas. Some of these species become invasive and harm their new environments. This series examines eight invasive species and investigates the various ways that people are attempting to manage them. This title explores the role of zebra mussels in introduced environments, how humans helped spread the species, the threats they pose to ecosystems, and efforts being taken to manage them. This book also includes a table of contents, two infographics, informative sidebars, a "That's Amazing!" special feature, quiz questions, a glossary, additional resources, and an index. AGES: 8 to 11 Focus Readers deliver captivating nonfiction topics, accessible text and vibrant visuals to build reading confidence and motivate young readers.