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ASK A PROF Q: I've read there may be a breakthough in controlling fire ants through biological means. Where does this research stand right now? -- Jerry Keel, Demopolis, Alabama Prof. Walter Tschinkel, fire ant ecologist, replies: A "breakthrough" may be an overstatement. There are two laboratories, one in Gainesville, Florida, the other in Austin, Texas, that are developing parasitic scuttle flies from South America for use in biocontrol. Releases began last year. The flies inject eggs into fire ant workers. Upon hatching, the larva makes its way into the ant's head, and eats all of its contents--brains, muscles and all. The head falls off, and the larva pupates inside it, emerging as an adult fly in a two to three weeks. Several species of such flies are quite specific in parasitizing only fire ants, and fire ants have evolved very specific defensive reaction to them. The most important is that when the flies are about, fire ants stop foraging, allowing competing species of ants to feed. It is hoped that this effect will allow native North American ants to compete more effectively with the imported fire ant. Several such fly species will probably be introduced so that the fire ant will be harrassed at all times of day and in all seasons. No one expects these flies to "control" fire ants. Rather, they will have an incremental effect in weakening its competitive ability. After additional parasites and diseases are introduced, the imported fire ant will probably become much like any native species of ant--not overly dominant, and much less abundant. Q: Forecasters are saying that this year is going to be a bad one for hurricanes. Are these expected to be primarily Atlantic storms? Or Gulf? And why is it going to be so bad this year? -- Bruce Mendleton, Tallahassee Dr. James Elsner, meteorologist, replies: For one thing, El Nino is gone so that will not be an inhibiting factor this season. With El Nino, the large scale weather and ocean patterns limit the development of hurricanes. Without it, the patterns are typically more favorable. Also, the upper level winds will be blowing in a direction that will limit the amount of debilitating shear. That will allow more storms to form. We are in a pattern in which the storms that do form will more likely occur somewhat farther to the north. With that said, indications are that we will see at least one hurricane in the Caribbean that could threaten the Gulf coast. An early season (July into early August) is also a possibility this year. |