BROWN TREE SNAKES CAN BE BAD

by Whit Gibbons

November 7, 2004

When someone takes a position that a government entity, be it federal, state, or local, is budgeting too much for environmental research, taxpayers should pay attention. Pay close attention. Because overspending on wildlife issues is not the problem. For example, a southern governor recently singled out certain wildlife biology studies for excessive spending and critics attacked as pork-barrel spending a program by the federal government to keep the brown tree snake out of Hawaii.

The criticism by Governor Sanford of South Carolina was that too much of the state's budget was being directed toward wildlife research on beavers and toward a book educating people about sharks. Maybe the governor has a complaint of substance that was not apparent to me, but almost any project can be made to look unnecessary or overfunded when taken out of context. Why a governor would take time to address issues that use such a trivial portion of the state's budget remains a mystery.

On a broader plane, we should always harbor at least a little suspicion when someone is anti-research, as new discoveries set the foundation for education. In other words, is the person saying that we already have enough knowledge and should not encourage acquiring more? Second, critics of research seldom put their complaints about directed spending in the context of how treasury dollars get spent on other projects that some of us might find wasteful, inefficient, and self-serving. Micromanagement of research is not a progressive approach to being a first-rate country on the forefront of science or a leader among the states in higher education.

As to the brown tree snake, why should anyone care if a snake gets into Hawaii? Here's why. Invasions by introduced species have had dramatic effects on the ecology of natural systems throughout the world. European rabbits brought to Australia in 1859 have devastated native animals and plants. An Oriental fungus, first observed on trees in New York in 1904, virtually eliminated native American chestnut trees. The zebra mussel is disrupting aquatic ecosystems of North America by replacing native species. The brown tree snake is the paragon of an invasive species that has caused severe problems on Guam.

Why some introduced species become rampant pests whereas others do not remains a mystery. A record of all accidental or intentional releases of alien species would reveal that most never survive for more than a few generations. Others may persist but never reach high population levels. For example, many cities in Florida have small, but persevering, colonies of inoffensive gecko lizards native to tropical Africa, Asia, and the West Indies.

The brown tree snake, found naturally throughout the Australian and Indonesian regions, was unintentionally introduced to Guam, presumably during World War II. It has become a serious threat to native wildlife. The evolution of natural defenses is a key biological principle underlying success or failure of invading species. The birds of Guam, having evolved in a situation with no significant predator on nests or young, have been demolished by the introduced brown tree snake. Brown tree snakes are constrictors with evil-looking vertical pupils, rear fangs and mildly venomous saliva, and a disproportionately large head. Individuals more than nine feet long have been found on Guam, which one government report estimates has as many as 13,000 per square mile.

They have devastated much of Guam's wildlife, information that would be unknown except for ecological research. Guam's native forest birds have been declared "virtually gone," and at least a dozen known only on Guam are now extinct "as a direct result of brown tree snake predation." The Hawaiian Islands fit the Guam model in having birdlife that has never been exposed to snake predators. Thus, Hawaii's ecology could be severely altered if brown tree snakes became established. Much of the current funding is to monitor cargo going from Guam to Hawaii to be certain a brown tree snake has not become a passenger.

Overspending on wildlife issues has never been the cause of government budget deficits. When people seek ways to save tax dollars, they do not have to look far, but looking at funding that increases environmental knowledge and education is the wrong direction.



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