Crop Damage Discussion

Example of damaged corn field ← Sandhill Crane Conservation

Efforts to Develop an Effective, Non-toxic Repellent to Prevent Crane Crop Damage to Corn

The past several decades have marked a dramatic change in the Upper Midwest's population of Sandhill Cranes. In 1981, ICF began monitoring regional crane population trends through the Annual Midwest Crane Count. The data gathered in the years since has revealed that cranes were moving into previously unoccupied locations while increasing in density in other areas. In 1990, ICF began an intensive study of cranes near the city of Briggsville, WI, to better understand the natural history of these birds. One practical application of this study was to help solve the problem of cranes damaging newly sprouted corn seedlings (see image above). ICF biologists reasoned that as the population grew, farmers would begin to experience increasingly severe and widespread damage to planted corn. ICF also recognized that traditional methods of crane deterrence, such as propane cannons that make loud noises, as well as other similar scare tactics, where not effective at preventing damage. On the contrary, these methods simply cause the cranes to move to other fields, thus not solving the problem at all.

Describing and predicting where and when crop damage might occur is difficult, as cranes are highly mobile and long-lived. ICF realized better information was needed about how cranes utilize various habitats during the time of year when they inflict the most crop damage (from planting until the seedlings are about two weeks old). During the spring and early summer, cranes predominantly use wetlands for nesting, and uplands (meadows, pastures, and cultivated fields) for feeding.

To begin the crop damage research, ICF first contacted farmers to see if they had any success with preventing crane damage; several had. One farmer in the study area said that when he pre-treated corn with the insecticide Lindane the cranes did not damage his germinating corn. ICF then began to track the use of Lindane by farmers and verified this finding. It was also noted that unlike traditional scare tactics, Lindane did not prevent cranes from continuing to forage in these fields. This confers a benefit to the farming operation, because cranes feed upon waste grain and harmful insects, such as beetle larvae, that can negatively impact yields.

However, there was still a problem. Lindane is a persistent, highly toxic, bioaccumulative chemical. Although ICF did not feel that Lindane was an ecologically sustainable solution, until there was an alternative there was no choice but to inform farmers that Lindane was effective at preventing crane crop damage. Next, ICF set out to identify and test the effectiveness of other, less toxic, compounds as deterrents.

Various substances that showed promise based upon avoidance by captive birds were tested in the field. ICF began testing alternative deterrents through field trials in the Briggsville study area so that crane habitat use could be monitored. In those field trials, only one compound showed real promise – 9,10 anthraquinone (AQ). Preliminary trials showed AQ worked as effectively to prevent crane crop damage as Lindane. AQ is a compound naturally produced by plants to protect their fruit from being eaten before ripening. It has low toxicity and low environmental impact.

With this breakthrough, ICF then focused on building a consortium of people to help move AQ through the federal regulatory process. Eventually our collaborators included: U.S. Environmental Protection Agency (EPA), the University of Wisconsin-Madison, the Wisconsin Department of Agriculture, Trade and Consumer Protection, Michigan and Minnesota agriculture departments, Michigan, Minnesota and Wisconsin Departments of Natural Resources, four farming organizations in these three state, the Department of Wildlife Services (USDA), many individual farmers, U.S. Senator Herb Kohl's Office, the IR-4 Project of Rutgers University, three local chapters of the Audubon Society, and Arkion (the manufacturer of Avipel® in which the active ingredient is AQ).

In March 2006, the EPA allowed AQ to be used for the first time by corn growers in Michigan, Minnesota, and Wisconsin. ICF plans to continue its research to verify that AQ is an effective deterrent in preventing crop damage by cranes. In the future, ICF hopes that nontoxic AQ can also be used to address other crop damage problems, such as blackbird damage to rice and waterfowl damage to wheat.



Click to download

Click on the image above to download the fact sheet "Protect your corn from cranes," a joint publication of ICF and the University of Wisconsin–Madison/University of Wisconsin-Extension.

The use of anthraquinone (AQ) to prevent crop damage by cranes is a win-win situation for both cranes and farmers. The use of AQ allows cranes to access critical food items in cultivated fields, such as waste grain and harmful insects, which are beneficial to the farmer. Additionally, farmers will not experience economic losses due to crop damage, or have to handle toxic seed treatments. Successful solutions such as this example are critical for advancing wildlife conservation on private lands, which composes over 2/3 of North America's land.

For more information on the availability of Avipel®, please contact Arkion at 1-800-468-6324.

Issue Update:

2012 was a record year for the use of Avipel® with

111,389 acres treated in WI
16,830 acres treated in MI
2,674 acres treated in MN

In addition, other states are using Avipel® to deter damage from pheasants and various species of black birds in rice and sunflower seeds, as well as with corn. Final permission for the use of the deterrent (a Section 3 label) was applied for in October 2010, making it likely that nationwide approval will be obtained in 2013.