• What are invasive species?

    Invasive species are plants and animals that have been introduced, whether accidentally or on purpose, into their current habitat. Invasive species can cause harm when they establish themselves at the expense of native plants and animals.

  • What is the difference between an invasive and an exotic species?

    Both invasive and exotic species are not native to their current habitat. While invasive species are harmful to their surrounding environment, exotic species do not necessarily cause harm. Mute swans, nutria and zebra mussels are three invasive species in the Chesapeake Bay watershed. Green crabs, sika deer and largemouth bass are three of the region’s exotic species.

  • How are invasive species introduced?

    Invasive species can be introduced to an ecosystem in a number of ways. Sometimes, non-native species are introduced accidentally through human trade, travel and tourism. Other times, non-native species are deliberately introduced as pets, for recreation or to control pests.

  • Are there invasive species in the Chesapeake Bay region?

    Yes. There are more than 200 known or possible invasive species in the Chesapeake Bay watershed.

  • How do invasive species affect the Chesapeake Bay region?

    After habitat loss, invasive species are one of the top threats to native plants and animals. They can cause harm when they establish themselves at the expense of native plants and animals, encroaching on their food or habitat. 

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  • Bivalve

    An aquatic mollusk whose compressed body is enclosed within a hinged shell. For example, clams, oysters and mussels are bivalves.

  • Crustaceans

    Aquatic arthropods (invertebrates) that have gills, joined legs and exterior skeletons. Crabs, shrimps, barnacles, amphipods and isopods are all crustaceans.

  • Delmarva Peninsula

    The land separating the Chesapeake Bay from the Atlantic Ocean. The Delmarva Peninsula falls within the states of Delaware (Del-), Maryland (-mar-) and Virginia (-va), from which it gets its name.

  • Ecosystem

    A natural unit formed by the interaction of a community of plants and animals with the environment in which they live. All of the elements of an ecosystem interact with each other in some way, depending on each other directly or indirectly.

  • Endangered species

    A species whose numbers are so small that it is in immediate danger of becoming extinct and needs protection to survive.

  • Exotic species

    Any introduced plant or animal species that is not native to a region. Exotic species are not always considered a nuisance or invasive.

  • Herbicide

    A substance that is toxic to plants and is used to destroy unwanted vegetation.

  • Native species

    A species that is native to the Chesapeake Bay region. It evolved on the North American continent and was present at the time of European colonization.

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