A British biotechnology company called Oxitec has genetically engineered a new breed of olive tree fly that could stop their natural counterparts from ravaging olive trees in Spain. SEE ALSO: 9 Bug Videos That Will Make You Squirm 
 
 Olive tree fly larvae eat through 15% to 30% of the crop each year, making them much more than a nuisance to anyone whose income depends on the fruit. To tackle this, Oxitec, a biotech company based in Oxford, UK, has submitted an application to the National Biosafety Commission in Spain to release a small contingent of male GM olive flies, in what would be the first field trial of its kind in Europe. The males are equipped with genes that cause any female offspring they sire to die while they are still in the larval stage, before they have had a chance to reproduce. Subscribe to New Scientist and get: 
 
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– How do you get rid of a population of bugs destroying your crops? Scientists are trying out a controversial method: spreading a gene that prevents females from reproducing. Males can live with the lab-inserted gene, but females die in the larval stage—which doesn't leave a lot of options for reproduction or the future of the species, New Scientist reports. In a lab experiment, this decimated the population in 10 weeks. Scientists at English firm Oxitec want to try their method in Spain, where they're awaiting the OK from Spanish authorities to kill off certain fruit flies that destroy some 15% to 30% of the olive tree crop each year. But genetic science watchdogs have concerns about the method, fearing, for instance, that altered populations could affect creatures outside their own species, Mashable reports. A similar experiment is already happening in the wild in Brazil, where the Oxitec team has altered males of a population of dengue-carrying mosquitoes. Some 96% of dengue mosquitoes around the city of Mandacaru have been destroyed, the company says.