Environmental activists last week petitioned federal authorities to place the monarch butterfly on the list of endangered species. They claim that the planting of genetically modified crops in the Midwest and the use of glyphosate are behind a severe drop in the monarch population.

The groups, the Center for Biological Diversity, the Center for Food Safety and the Xerces Society, say that the butterfly populations are declining because of farmers’ use of glyphosate resistant, or Roundup Ready, crops. They blame the Roundup Ready system for the loss of milkweed, the sole diet of the monarch butterfly caterpillar.

However, the petition is a misguided attack on genetically modified crops and pesticides and could actually hurt the environment, according to Rick Robinson, Iowa Farm Bureau Federation environmental policy advisor.

Benefiting conservation

Crops with genetically modified organisms (GMOs) and pesticides, like glyphosate, have allowed farmers to reduce tillage and conserve soil, Robinson said. In addition, increased yields from biotech crops have allowed farmers to install buffer strips, wetlands and other areas that have provided additional habitat for the monarch butterfly and other wildlife in Iowa and other states, he said.

"The petition is likely to be popular among anti-GMO and anti-pesticide groups, but the fact is that GMOs have many benefits and have been scientifically proven time and time again to be safe for the environment and people," Robinson said. "As many as three federal agencies are involved in approving their use."

Robinson said there are several known reasons for a decline in the number of monarchs returning to overwintering sites in Mexico, including loss of their overwintering habitat and unfavorable weather. However, he said, the cause for the milkweed decline is less certain.

"The ecology of the system is too complex to blame Roundup for the decline of milkweed or monarchs. The Endangered Species Act can’t affect unfavorable wet and cold weather," Robinson said.

Promoting milkweed

A better approach to building up milkweed populations is to target new production on non-crop areas, such as road right of ways, backyards, gardens and acres in the Conservation Reserve program or Environmental Quality Incentives Program, Robinson added. The expansion and restoration of overwintering habitat in Mexico would also be helpful, he said.

"Folks who are concerned about the loss of monarchs can help by creating habitat on their property, work with youth groups and businesses to help them create habitat or help local groups restore native milkweeds and nectar sources to roadsides and public and private lands," Robinson said.