We have a World Cup fanatic on our staff (Helmuth Rogg, the Insect Program Supervisor). His bad case of soccer fever has infected some of the other staff, including me—though compared to him, the rest of us have a mild case. At first glance there is no obvious connection between the World Cup and invasive species, but think again.
Global trade and travel is how most invasive species move from continent to continent. A huge event that draws people from all over the world is sure to involve some unseen hitchhikers. Spectators arriving by plane, ship, rail, car, and even on foot may be traveling with invasive company. Here are some examples from closer to home:
Planes arriving at PDX from certain airports (e.g., Louisville, KY) carry live Japanese beetles. ODA inspectors look at the high-risk planes and find live beetles every year. This pest is on the State’s list of the 100 Worst Invasive Species to keep out, and once again this summer, there will be a treatment project at PDX to eliminate a small population that has established there.
Ships and boats carry invasive species in ballast water and attached to their hulls. The recent discovery of an invasive sea squirt (Didemnum vexillum—also on the State’s 100 Worst List) in Winchester Bay and in Charleston harbor shows how Oregon is subject to invasion by sea.
Pests can travel by rail, too. Several years ago. imported fire ant (100 Worst List) was found in a railroad car carrying cotton seed for cattle feed when it arrived in Oregon.
Cars and trucks also carry non-traditional hitchhikers. An Australian scientist came up with an ingenious way of quantifying “car-borne flora.” He collected the sludge from a commercial car wash, extracted the oil, and sifted out the seeds. When he planted them, an astonishing 18,000 seedlings appeared representing 259 species——predominantly weeds (Wace 1977). I wish someone would do this study in Oregon.
Even pedestrians can transport invasive species. World Cup spectators in South Africa should take notice of this story (Lowe 1999): “I returned from one trip to Africa to find dried mud caked to my sandals. Examining it closely I found a trove of organic riches: bits of straw, grass seed husks, flakes of snail shell, four seeds and some fungal treads bearing spore heads—a forensic record of my trip lay scattered before my eyes. One of the seeds was nearly as big as a dried pea, and I thought of sprouting it to see what it was, but a tiny insect later drilled an exit hole in one side.”
Many of the foreign World Cup spectators will no doubt return from Africa with carved masks and other wooden handicrafts. It wouldn’t be unusual for ODA to get a call from a concerned traveler who has noticed little piles of sawdust accumulating under their souvenir. The powder post beetles that are slowly turning their handicraft into sawdust have probably already been transported around the world, but there are other species we’d be wise to keep out so we’re happy to receive the calls.
So what’s a traveler to do? The fanatics aren’t going to stay away from the World Cup, nor should they. You and I and all the other travelers/drivers/boat owners can make a difference by cleaning our shoes, vehicles, and boats before leaving one area to go to another. It is that simple. If everyone made a habit of doing that, there would be a lot fewer hitchhikers traveling with tourists, motorists, and World Cup fans. Oh and if your souvenir shows signs of living inhabitants, put it in the freezer overnight——that usually takes care of the problem.
Lowe, T. 1999. Feral Future. Penguin Books Australia Ltd. 380 pgs.
Wace, N. 1977. Assessment of dispersal of plant species – the car-borne flora in Canberra. Proc. Ecol. Soc. Aust. 10:168-186.