Native species in Hawaii: 0
Introduced species: 2
I list here 2 introduced species of snakes to the islands. This number is not based on breeding populations, nor on actual types of snakes present, but more as a guess of potential threat snakes. These snakes I would list as the Brown Tree Snake (Boiga irregularis) and the Boa Constrictor (Boa constrictor). The boa constrictor is a threat because of its use as a pet that could potentially be released. The brown tree snake is a species that is known to cause major damage in other places - most notably, Guam.
Guam, like Hawaii, has no native snake species. Its bird fauna had adapted to life without slithering predators. Then, in 1950's the US military probably accidentally introduced this species on cargo from other Pacific islands. The result today is a massive invasion of these snakes. Densities are around 13,000 snakes per square mile. Very few native bird species exist. Reports from friends that have worked in the field, tell me that there are no bird sounds when you walk through the bush. Its a sad story, and that's what makes the Brown Tree Snake Hawaii's number one most unwanted species.
Just under a dozen snakes have been collected in the last two decades, having fallen out of the the wheel-wells of incoming planes. Its a number high enough to make Hawaiian officials very scared. If a snake like this got to the islands it could do the same thing as it did on Guam. Besides the birds, humans should be wary as the snake is dangerously venomous.
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