How Technology and Conservation Tillage Improve Bird Habitat
Since B.t. cotton came on the market in 1996, songbird populations that frequent habitats around cotton fields have grown 20 percent in Arizona, 37 percent in Mississippi, 34 percent in Alabama and 10 percent in Texas, according to the North American Breeding Bird Survey. While there is no hard data to confirm the specific link between biotech farming and increased songbird and ground-nesting bird populations, Jim Byford, dean of the University of Tennessee-Martin's College of Agriculture and Applied Sciences who has a Ph.D. in wildlife biology, says he has "no doubt" that the two are directly linked. "With the GMO cotton, we don't need to spray much at all," said Byford, who grew up on a Tennessee cotton farm and still hunts in areas alongside cotton fields. "That has meant more insects that birds of all kinds use for food.” Specifically, Byford says he has seen an increase in brown thrashers, indigo buntings, towhees, and song sparrows in the low-lying brush that is typically found on ditch banks and other areas alongside cotton fields.
But he also believes quail and other birds are actually nesting in cotton fields - something he never witnessed as a child and rarely before biotech cotton was introduced in 1996. Farmers growing biotech soybean and cotton, in particular, are more likely to practice conservation tillage, a farming method where farmers plow less and leave more crop residue on the ground for wildlife - like quail and pheasants - to nest in.
In its "greenest" form, called no-till, soil is left virtually undisturbed from harvest to planting. There's been a 35 percent increase in no-till acres in the U.S. since 1996, according to a study by the Indiana-based Conservation Technology Information Center (CTIC) that strongly supports the conclusion that these crops developed through plant biotechnology are facilitating the continued expansion of conservation tillage, especially no-till. Roughly 75 percent of no-till soybean acres, and 86 percent of no-till cotton acres are planted with biotech varieties.
Bob Janssen, a consultant with the Minnesota Department of Natural Resources, agrees that conservation tillage can help prevent the creation of more "black deserts" — plowed agricultural fields that have been stripped bare of the nourishment and cover that birds need. "By plowing and spraying less, retaining crop residue plus taking other steps like preserving wetlands, farmers can have a greater positive impact on bird populations than anyone," Janssen says. For ground-nesting birds like the meadowlark, quail, and pheasant, no-till farmland provides nesting material. These birds weave homes from crop residues and other material that are not available in a plowed field. Plowing and mowing destroy those nests that are built, since meadowlarks nest in the farming months of June and July. "Conservation tillage practices which reduce surface disturbance during the nesting and brood-rearing period unquestionably save many nests [and] chicks," concluded Ralph Dimmick and William Minser in their study, Wildlife Benefits from Conservation Tillage. Crop mulch also helps protect these birds from predators.
Because biotech crops such as cotton require less spraying, birds in and around these fields have more grasshoppers, caterpillars and other insects to feed on. In no-till fields, for example, quail need just 4.2 hours to find and eat the insects necessary for survival — less than one-fifth the time it takes to obtain the same number of insects in a conventional-till field, according to the CTIC. (www.whybiotech.com via AgNet 2/15/04).
