November 1, 2004
Wild turkeys don't gobble up crops, say Purdue experts
WEST LAFAYETTE, Ind. - Wild turkeys are often accused of a crime they don't commit, say Purdue University researchers who claim the birds are victims of being in the wrong place at the wrong time.
A common perception among farmers throughout much of the United States is that turkeys, which are becoming more common in the agricultural landscape, knock down and eat crops ranging from corn and soybeans in the Midwest to grapes in California's vineyards. Research by Gene Rhodes, professor of wildlife ecology, and Brian MacGowan, Extension wildlife specialist, has found that deer and raccoons, and not turkeys, are the crop-munching culprits.
Their project was designed not only to solve the "whodunit" crop mystery, but also to address public perceptions and misconceptions about wildlife damage in agricultural fields.
Crop damage by wildlife is no small problem. Experts estimate agricultural producers suffer wildlife-related losses that exceed $4.5 billion per year in the United States. In northcentral Indiana, 82 percent of the 529 farmers participating in the Purdue study reported some degree of wildlife damage to crops.
Rhodes and MacGowan outfitted a small army of wild turkey, raccoons and white-tailed deer with various tracking devices to monitor their movements throughout the fields of northcentral Indiana. Members of the research team also walked the fields, identified which species caused the damage based on what they saw, and spent time observing and photographing wildlife in the fields throughout the growing season.
"The time we have spent observing these animals in the field and attempting to get that behavior on tape is a unique aspect separating our study from many past efforts," MacGowan said.
Unlike turkeys, deer and raccoons are largely nocturnal, meaning they are active at night
"Our video data will allow producers to experience the corn field environment at night, when the majority of damage occurs," he said.
Two years of fieldwork gave the researchers a solid set of data vindicating turkeys. Over the past two years, deer and raccoons caused 95 percent of the damage in the fields surveyed, Rhodes said.
"During the two growing seasons we surveyed, not a single incident was caused by turkey," he said.
The problem with turkeys is that they show up at the crime scene during daylight hours, after the damage is done by the night-feeding deer and raccoons, he said.
"Turkeys do enter these fields, there's no doubt about that," Rhodes said. "But turkeys do not go in there and knock over cornstalks; they go in to eat waste grain and bugs."
MacGowan said, "I have sat in cornfields at night and recorded raccoons aggressively knocking down cornstalks all around me."
When people see turkeys walking through fields in the morning, they tend to assume that turkeys are responsible for the damage.
The information from this study will be helpful to organizations such as the National Wild Turkey Federation, which supports scientific studies of wild turkey management.
"Wild turkeys are perceived to be damaging crops because they are so visible, but the evidence doesn't support the perception," said James Earl Kenname, senior vice president for conservation programs at the National Wild Turkey Federation.
Rhodes said state and federal agencies receive numerous complaints each year from farmers claiming crop damage from turkeys and that the Indiana Department of Natural Resources has received more complaints in recent years.
"In the vast majority of these cases, it turns out that the perception of what did the damage is not really what did the damage," he said. "Our goal is to get solid research on where these animals spend their time and what they're doing in this landscape. We want to shed some light on this situation so we can begin to come up with solutions for landowners."
Rhodes and his colleagues also surveyed farmers to assess their perceptions of wildlife, the extent of damage to their crops and what steps they've taken to mitigate that damage. This information will help in developing educational materials to help landowners address numerous wildlife problems, MacGowan said.
Among the materials MacGowan and Rhodes will develop is a video showing deer and raccoons eating corn and soybeans in a field.
"You can tell people what's causing all the damage in their fields, but until they actually see it, they probably won't believe it," MacGowan said.
Future work on the project will include determining where in fields the most damage occurs and which environmental attributes are associated with higher levels of damage.
"Our next goal is to figure out how landscape features influence the likelihood of crop damage," Rhodes said. "Does proximity to roads, forest patches or houses make a difference? What about the shape of the field?"
Ultimately, the study will benefit farmers and wildlife populations alike.
"As we learn more about crop damage by wildlife and how the public perceives that damage, we'll develop better strategies to minimize losses to farmers, while improving public perceptions of wild animals in the fields," Rhodes said.
The Indiana Department of Natural Resources Department of Fish and Wildlife, the National Wild Turkey Federation, the Indiana chapter of the National Wild Turkey Federation and Purdue University provided funding for this project.
Writer: Jennifer Cutraro, (765) 496-2050, firstname.lastname@example.org
Sources: Gene Rhodes, (765) 494-3601, email@example.com
Brian MacGowan, (765) 647-3538, firstname.lastname@example.org
Related Web sites:
A publication-quality photograph is available at http://ftp.purdue.edu/pub/uns/+2004/rhodes-crops.jpg
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