Brown tree snakes came to Guam, naturally, on a plane (and on boats). In the 60 years since they arrived, the Brown Tree Snake has “ate almost all the birds.” There are only a few hundred birds left on the island.
The decimation of the bird population, in turn, has lead to an explosion in the spider population. During rainy season there are “40 times more webs” on Guam than on nearby islands.
The snakes — which can grow to 10 feet long — have also been “biting residents and even knocking out electricity by slithering onto power lines.” The poisoned mice targeting the snakes with be attached to “little parachutes” which the hopes that they get caught up in the trees where the snakes live.
The National Wildlife Research Center is working on developing a more sophisticated solution:
As a first step in development of an artificial attractant, NWRC scientists successfully characterized the odor of dead and decomposing mice. The next step will be to develop a suitable matrix in which this “mouse essence” can be embedded. Chemical cues involved in brown treesnake behavior, however, are complex and cues that elicit strong responses in the laboratory often have diminished effects in the field. So far, artificial matrix compounds as diverse as tofu, plaster-of-paris, and gelatin have shown promise as attractive lures but snakes have shown only limited interest.
Why is so much effort being poured into solving this problem? The Brown Tree snake could be headed to Hawaii next. Despite extensive screening efforts, “eight brown tree snakes have been found on Oahu since 1981, hitch-hiking on aircraft from Guam.” An economic analysis found that proliferation of the Brown Tree Snake in Hawaii could cost over 2 billion annually from “from medical incidents, power outages, and decreases in tourism.”
The problem illustrates the substantial economic and health risks posed by invasive species in an increasingly global economy. Other risks include the Emerald ash borer on imported Valentine’s Day flowers, the brown marmorated stink bug on citrus fruit and killer algae that grows in tropical fish tanks.