The European Green Crab (Carcinus maenas) is a small, invasive crab species native to the coasts of Europe and northern Africa. It has a distinctive green shell, often with hints of brown or yellow, and can grow up to 4 inches wide. This crab thrives in various habitats, including estuaries, rocky shores, and sandy beaches. Since its introduction to North America in the 1800s, the European Green Crab has spread rapidly, causing ecological and economic impacts. It preys on native shellfish, such as clams and oysters, and competes with local species for resources, disrupting marine ecosystems.