Barn Owl Connections and Recovery
Marla Mertz, Marion County Conservation
Barn owl populations have been on some folk’s radar in Iowa for many years. As I was just a newbie in the conservation field in the early 80s, Iowa Department of Natural Resources (IDNR) Wildlife Diversity staff members Bruce Ehresman and Pat Schlarbaum were the first to introduce me to raptors, their importance, and a mission to try and raise the population of a ghostly owl. Bruce and Pat were also the first to invite me to tag along on a few barn owl placements and placing barn owls in my arms to await the barn owl box preparation in private landowners’ barns.
The common barn owl is found on every continent except Antarctica, but is not quite so common in Iowa. It is considered a savanna species that nests and roosts in secluded areas. Dramatic changes over the years that include loss of habitat, severe winter weather, the conversion of grasslands and pastures to row crops, the loss of large cavity nest trees and wooden farm buildings, and predation have had a serious impact on this unmistakable heart-shaped face bird. Barn owls hunt opportunistically, eating anything available in times of need. Mice and voles are the staple of the barn owl diet, but rabbits, starlings, and maybe a few bats and frogs will also be eaten. They are valuable allies to us and their environment as each owl can eat one to six rodents a day. If you are a farmer, that’s basically the best rodent control out there. As with all raptors that depend on prey population trends, their susceptibility to pesticides and other rodent control are very high.
As with many species that are endangered, their recovery and research is ongoing. It is not a hurried and human scheduled clock. The barn owl was listed as an Iowa endangered species in 1977. It wasn’t until 2003 when I received a phone call from a lady who was preparing to repair the cupola on her historic 95-year-old barn and noticed a barn owl pair raising a family. She postponed the repairs and let me know that Bruce Ehresman and Beth Brown had installed a nest box in her barn 18 years prior and this was the first sighting of an owl pair. The landowner was delighted to allow me to monitor the owls and listen to her stories of them carrying rabbits and other prey into the barn to feed the four young. Another “owl” connection was made that summer. As an educator, this historic moment of barn owls in Marion County was going to go as far as I could take it. I was able to gather many owl pellets over the course of the young growing up in hopes that we could learn a little more about the owls, their prey, and the ecosystem of their territory.
Numbers in research is always important. In 2003, there were only six barn owl nestings reported in Iowa. In the fall of 2003, Cathy Hones, biology teacher at Pella High School called requesting ideas for her students. The Honors biology students were looking for research projects by collecting “actual data.” Their learning would be enhanced by visiting Iowa State University to learn to compile their data and process research. Well, this sounds like an endangered owl species in Marion County kind of research to me!
What a great feeling to be able to provide actual data, knowledge of the area and the opportunity to have “results” of their findings. These students, weighed, measured, and dissected each individual pellet, and were able to identify prey species eaten within the owls’ territory while learning types of teeth, shapes of skulls, and appropriate ID markers. They compiled their data in all necessary forms and focused on prey and ecosystems throughout their reports. In my tenure, this was one of the most fascinating compilations and timed efforts of the biology teacher and her students.
Bruce Ehresman is currently (retiring March 2018) a Biologist and avian ecologist for the IDNR Wildlife Diversity Program and has continued the statewide research effort for Iowa’s barn owls for over 35 years. 2017 has brought good news to the populations of the barn owl. So far this summer 25 nesting reports (plus one additional just confirmed recently) have been made. Bruce has noted in his press releases that Chickasaw County has reported a nest and this is the first report prior to 1960. This is GOOD NEWS!
- Press release from Iowa DNR 11/2/17 with updated info: Barn Owl Nesting Bonanza
It is still unknown exactly how many barn owls reside and nest in Iowa. You can help the IDNR by reporting any sightings of this rare animal to the Wildlife Diversity Program at (515) 432-2823.
What can I do to help?