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Course Outline

Introducing non-native species into state or federally controlled waters can upset the ecosystem and hurt the environment by clogging the waterways and crowding out native species.

  • Aquatic nuisance species in Hawaii include various plants.
    • One species is Gracilaria salicornia, also known as “gorilla ogo” because it resembles a larger, more aggressive version of the edible ogo seaweed. It forms extensive tangled mats of orange, green, and purple, which literally blanket reefs.
    • Other introduced plant species include Kappaphycus spp. (common name: Agar Agar Pulau, Red Alga, etc.) and Acanthophora spicifera (common name: Spiny Seaweed), just to name a few.
    • These species can spread on the tides, grow rapidly in ideal conditions, and smother and kill coral reefs that protect our shoreline from erosion.
  • Although recreational boaters did not play a significant role in introducing these species to Hawaii’s nearshore waters, invasive freshwater species can be spread easily by recreational boats visiting lakes and streams. Warm water temperatures and abundant sunlight allowed Salvinia molesta (common name: Giant Salvinia, etc.) to almost completely cover Lake Wilson on the island of Oahu.
  • Quagga mussels, zebra mussels, milfoil, hydrilla, and other species have become major problems on the U.S. mainland.
Hydrilla
Quagga and zebra mussels
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