There are several routes for introduction of non-native species. Some species were accidentally introduced to Hawaii like the rat, fire ants, coqui frog, mosquitos, and asiatic rhinoceros beetle. Some are species brought in for cultivation that spread to wild areas like miconia, pigs, and goats.

In 2026, Hawai'i remains a unique case study in biogeography and evolutionary vulnerability. Because the islands are the most isolated archipelago in the world, the native species evolved for millions of years without natural predators like mammals, snakes, or large amphibians. This led to a loss of natural defenses; for example, many native plants lost their thorns, and several bird species became flightless or ground-nesting. When humans began arriving—first Polynesians and later Europeans—they brought alien species such as rats, feral pigs, mongooses, and mosquitoes. In 2026, the lack of natural "checks and balances" allows these invaders to outcompete and prey on the defenseless native flora and fauna. The tropical climate of Hawai'i also provides a year-round "growing season," allowing invasive pests like the Coqui frog or Little Fire Ant to reproduce rapidly and spread through nursery plants and cargo, a process that continues to challenge the state's conservation and biosecurity agencies in 2026.