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  • On the island of Guam, the brown tree snake has decimated the island’s bird populations and is the cause of frequent power outages. Should it ever get to Hawaiʻi it could do similar damage. Photo © TNC
  • Wild pigs destroy native vegetation, accelerate erosion, spread weeds and pollute the water supply. Their wallows create breeding sites for mosquitoes that spread diseases to Hawai'i forest birds. Photo © Jack Jeffrey
  • Introduced to Hawaiʻi as an ornamental, Australian tree fern spreads like wildfire, sending spores up to seven miles on prevailing winds. Aggressive and fast-growing, it can take over the forest. Photo © Chad Riley
  • Kappaphycus, an invasive smothering sea weed, can double in size in just 15-30 days, growing into thick, tangled mats that suffocate reefs and marine life. Photo © Chris Spezzano
  • Miconia casts a dense shade and kills everything beneath it, and its shallow roots cannot hold the forest soil. Over time, a diverse native forest becomes a single-species miconia forest, prone to landslides. Photo © TNC
  • Red fire ants have a toxic sting and are voracious predators of beneficial insects. They destroy germinating seeds and the fruit of many plant crops. Should they reach Hawaiʻi, they could wreak havoc on the state's economy. Photo © CGAPS
  • Though it yields fruit and wood, strawberry guava forms dense thickets that crowd out native trees and destroys the watershed services they provide. Photo © Jack Jeffrey
  • Leather mudweed, or Avrainvillea alamadelpha, is an invasive seaweed that traps sediment, creating an oxygen-starved marine environment that overwhelms native algae and seagrass. Photo © Marion Ano
  • The coqui frog is not much bigger than a quarter, yet its loud, incessant call has adversely impacted Hawaiʻi real estate values, while its appetite for insects threatens the balance of native ecosystems. Photo © Rob Shallenberger
  • Axis deer eat native vegetation and contribute to erosion. They have already destroyed native forests on Lānaʻi and Molokaʻi, and could do the same on Maui. Their introduction on Hawaiʻi Island is cause for alarm. Photo © Eric Nishibayashi
  • Fireweed is a rancher's nightmare.  This daisy-like plant invades pastures and is toxic to livestock when eaten, causing illness, liver-malfunction and even death in severe cases. Photo © Forest and Kim Starr
  • Don't let its striking flowers and exotic fragrance fool you. Kāhili ginger is an invasive plant that chokes out the natives and takes over the forest floor. Photo © Ethan Welty
  • Banana poka is a non-native vine that has smothered over 70,000 acres of native forest. Hardest hit have been the state’s koa forests, which supply Hawaii’s premier hardwood and support many rare birds and plants. Photo © Ethan Welty
Silent Invasion
Hawaii's Alien Invaders

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