Have scientists investigated how GM crops affect wildlife?
Yes. In 1999 the government asked an independent consortium of researchers, led by NERC's Centre for Ecology & Hydrology, to compare how growing both genetically modified and conventional oilseed rape, beet and maize affected farmland wildlife. The government used the results to help decide whether to allow the GM crops to be grown commercially in the UK.
The research was called the Farm Scale Evaluations, and was the world's largest environmental impact study of genetically modified crops. It ended in 2005. Over six years, scientists monitored wildlife in 273 experimental fields.
The results showed that GM sugar beet and oilseed rape, as managed in the trials, were worse for wildlife than conventional varieties, but that GM maize was better. The results were not because of the genetic modifications themselves, but because of the different weedkiller regimes. The team found that the beet and oilseed rape fields contained fewer of the weed seeds that provide food for wildlife, and they discovered fewer bees and butterflies used GM beet crops because there were fewer flowering weeds to provide nectar.
In the trials, conventional maize supported the least plant and animal life, with fewer weeds, seeds and insects than GM maize.
New research suggests that farmers could modify the weedkiller regime used on GM sugar beet crops so they can cope with more weeds than conventional varieties, which would be good for wildlife.
No crops have been approved for commercial growing in the UK.