The unwelcome and unstoppable cane toad is wreaking havoc on Australia's ecosystems.
    1. Watch the video above, and then answer these questions.


      What are some predators of the cane toad in Australia?

      The cane toad has almost no predators in Australia. The toads are poisonous to almost all potential predators—even the saltwater crocodile. Human beings are the most powerful and effective predator of cane toads in Australia!

      In the cane toad's native habitat of Central and South America, it has many natural predators. Caimans (a relative of the crocodile), snakes, birds, and even fish prey on the cane toad.

    2. Cane toads excrete a toxic substance that makes their skin poisonous. Where are the glands that excrete this poison?

      The poison is spread from glands on the cane toad's shoulders.

    3. What do cane toads eat?

      "Anything that fits in their mouth!" according to one biologist.

      The toads do not limit their diet to living things. According to another naturalist, cane toads will even eat marbles and golf balls!

    4. Cane toads are not native to Australia. Why were they introduced?

      Cane toads were introduced as a pest-control device. Farmers hoped the amphibians would eat insects that damaged sugar-cane crops.

    5. Did the introduction work?

      No! According to the video, the "toads ate everything except the insects they were brought in to kill!"

  • Term Part of Speech Definition Encyclopedic Entry
    amphibian Noun

    an animal able to live both on land and in water.

    cane toad Noun

    animal (amphibian) native to the Americas and considered an invasive species in Oceania and islands of the Caribbean.

    crocodile Noun

    reptile native to parts of Africa, Asia, and the Americas.

    crop Noun

    agricultural produce.

    Encyclopedic Entry: crop
    excrete Verb

    to discharge a substance from the body.

    farmer Noun

    person who cultivates land and raises crops.

    gland Noun

    group of cells that secretes a chemical useful for the body to function.

    insect Noun

    type of animal that breathes air and has a body divided into three segments, with six legs and usually wings.

    naturalist Noun

    person who studies the natural history or natural development of organisms and the environment.

    pest control Noun

    process of removing unwanted species (pests) from a specific geographic area.

    poison Noun

    substance that harms health.

    predator Noun

    animal that hunts other animals for food.

    sugar cane Noun

    tall grass that is harvested to extract sugar from its sap or juice.

    toxic Adjective