Oct. 30 (UPI) -- Fields planted with cover crops offer migrating birds an ideal place to rest and recharge, according to a new study by researchers at the University of Illinois.
With much of the Midwest's grasslands converted into farmland over the last century, there are fewer and fewer places for birds migrating across North America to stop for some shut eye and food.
"Now that agriculture is the dominant landscape, they're finding it harder to get the resources they need on the way to their breeding grounds," Cassandra Wilcoxen, a graduate research assistant, said in a news release.
When Wilcoxen and her research partners tracked the movements and patterns of migrating birds -- 6,133 individual birds comprising 52 species -- passing through corn and soybean fields with and without cover crops, they found fields with cover crops consistently hosted the largest numbers of birds.
"We think cover crops, such as cereal rye, likely provide migrating birds with more vegetation and a safe area to escape from the elements and from predators," Wilcoxen said. "Cover crops also increase insect abundance, another food source for birds."
The planting of cover crops can help reduce erosion and runoff. It can also help replenish nutrients in the soil. Researchers hope more research will help them develop best practices to ensure cover crops can be planted in ways that best benefit migrating birds.
Most cover crops are planted in the fall and killed in the spring, but exactly when to plant and kill -- and how -- can make a difference.
"Some grassland birds nest in the spring, so in order to give birds the time they need, farmers may need to hold off terminating their cover crop," Wilcoxen said. "Those are the sorts of recommendations that will require more research. It's true of any new farming practice. You have to play around with it to get it right."
Researchers shared their analysis of seasonal bird behavior on farmland in a new paper published this week in the journal Agriculture, Ecosystems & Environment.