They floated down from the sky Sunday — 2,000 mice, wafting on tiny cardboard parachutes over Andersen Air Force Base in the U.S. territory of Guam.
But the rodent commandos didn't know they were on a mission: to help eradicate the brown tree snake, an invasive species that has caused millions of dollars in wildlife and commercial losses since it arrived a few decades ago.
That's because they were dead. And pumped full of painkillers.
The unlikely invasion was the fourth and biggest rodent air assault so far, part of an $8 million U.S. program approved in February to eradicate the snakes and save the exotic native birds that are their snack food.It's not just birds the government is trying to protect. It's also money.
Andersen, like other large industrial complexes on the Western Pacific island, is regularly bedeviled by power failures caused when the snakes wriggle their way into electric substations — an average of 80 a year, costing as much as $4 million in annual repair costs and lost productivity, the Interior Department estimated in 2005.
OK, I'll give the CBA a try. Let's suppose that the cost of the creepy-drugged-mouse snake eradication program ($8m) consists of eight annual payments of $1m over the next eight years. At 5% discount rate, the present value of the costs is $6.46m.
Now let's consider the benefits. Because the story uses the language 'as much as' $4 million in annual prevented repair costs, I'm going to be super conservative and assume the savings are half that at $2 million per year. If that savings begins after complete eradication of the terrorist snakes (after 8 years) and lasts for 10 years (again being conservative--I could have made this a perpetual savings and really jacked up the benefit number), the present value of the cost savings alone is $10.45m.
And that doesn't even account for the benefits of keeping around the Guamian (is that a word?) exotic birds.