Q: What are “native species”?
A: Plants and animals that arrived at a location (Hawaiʻi, for example) without human assistance (via wind, wings, or waves), and their descendants, some of which may have changed over millions of years to look or act quite different from their ancestors.
Q: What about a native Hawaiian species?
A: Plants and animals first started colonizing the Hawaiian Archipelago via wind, wings, and water currents, millions of years before people arrived. The successful ones spread, populating new habitats and changing slightly over countless generations, resulting in one or more new species, some of which look or act quite different from their ancestors. Species that are found only in one geographic location are considered endemic. Some examples of endemism include Hawaiʻi’s honeycreepers, silverswords (ʻahinahina), happyface spiders (nananana makakiʻi), longnosed butterflyfish (lau-wiliwili-nukunuku’oi’oi), and all of our freshwater gobies or oʻopu. Ninety percent of the native plants are endemic to Hawaʻi and some even to a particular island or valley.
Q: What are non-native species?
A: All species that arrived at a location with people or as a result of our activities or conveyances (planes, ships, etc.) whether intentionally or unintentionally. Some synonyms include introduced species, exotic species, and alien species.
Q: What are “invasive species”?
A: Invasive species are non-native species whose introduction does, or is likely to cause, economic or environmental harm, or harm to human health. Some synonyms include alien pest species, and harmful pest species, or harmful non-indigenous species.
One of the best examples of an invasive species is the mosquito. Hawaiʻi did not have mosquitoes until they were introduced in a barrel of drinking water on whaling ships in the 1800’s. Mosquitoes brought and spread diseases like avian malaria and pox which sicken and kill birds. Today, many native bird species are unable to live at lower elevations where mosquitoes live and continue to transmit these diseases. Mosquitoes are also vectors of spreading diseases to humans like dengue and zika.
Q: Aren’t all non-native or introduced species also “invasive species”?
A: No. The vast majority of plants and animals that are introduced to a new location outside their normal range do not have the characteristics that tend to lead to becoming invasive either in an agricultural or natural setting. Examples of non-native plants that are not invasive include pineapples and plumeria.
Q: I’ve heard kalo (taro) and ti referred to as Canoe Plants. What are those?
A: Polynesian voyagers brought with them about 34 species of plants and animals when they arrived in voyaging canoes hundreds of years ago. The plants are sometime called “canoe plants”, or more generally, “Polynesian introductions”. As such, they are non-native species, but because of their cultural significance, we tend to refer to them with this distinction. Examples include kalo, banana, sweet potatoes, coconut trees, dogs, Polynesian pigs, and more.
Q: Why should I care about invasive species?
A: Invasive species affect everyone. Our buildings are eaten by termites; our water supply is at risk because the native forest plants are being replaced by fast-growing plants that are less effective at attracting moisture and allowing it to seep into the ground; our local-grown fruits and vegetables are attacked by fruit flies and other pests; a new species of fire ant is stinging farmers and homeowners; and reefs that shelter fish and protect our shorelines are smothering in invasive seaweed. We have enough to worry about, but the future will be much more dire if we do not stem the arrival and spread of new invasive plants, animals and diseases, and limit the impacts of the ones already present. We can succeed, and we must, if we want our kids and grandkids to enjoy all the things we love about Hawaiʻi. We must work together to make it a high priority for our government, and ourselves to do all we can to protect Hawaiʻi.