State wildlife experts are crediting a series of mild winters and an abundance of meadow vole prey in grasslands for a nesting boon for barn owls, primarily across southern Iowa.
So far this summer, the Iowa Department of Natural Resources (DNR) has received 25 reports of barn owl nests, most coming in the last three weeks, including a nest in Chickasaw County which is the first report since before 1960. This is the fourth year in a row that the number of reported nesting barn owls has increased. The barn owl has no federal listing but is listed as a state endangered species in Iowa.
“This is really great news that things are going well for barn owls,” said Bruce Ehresman, wildlife biologist with the Iowa DNR.
He said many of the calls are coming from ag producers who find the owls nesting in their grain bins or silos while preparing to move products. He said grain bins are perfect for nesting barn owls – the structure keeps invaders, like raccoons, out and keeps the young in, until they can fly. Owls aren’t too picky, he said. They will nest on the floor of the bin or on top of any grain stored within it.
“What we have been telling farmers is that if they can wait for a week or two, the owls will likely fledge and the issue will resolve itself. Once the birds are gone, owners can close off the owl entry points to prevent them from again using the grain bin as a nesting site,” Ehresman said.
He said the producer should call their local conservation officer or wildlife biologist to report nesting barn owls, and if waiting for young to fledge is not an option, then there may be an opportunity to work with a local wildlife rehabilitator.
“We really would like to leave the young alone if at all possible. Moving them is the absolute last resort,” he said. “We want to minimize nest disturbance to avoid having the adult abandon the nest, and we strongly encourage birders who are looking to add barn owl to their list to view them from a distance.”
Since the owls are using the area to rear their young, Ehresman has been encouraging producers to install a nesting box as an alternative to the grain bin. The Iowa DNR has information to build and install barn owl boxes on its website at
https://www.iowadnr.gov/Portals/idnr/uploads/education/Species/birds/BarnOwlBrochure.pdf
“We’ve been installing nesting boxes on posts at different locations for about a year and we are seeing use, which is exciting,” Ehresman said.