In the Central San Joaquin Valley, Barn Owls until fairly recently, nested mainly in palm trees, barns and haystacks. The parent birds do not even make a true nest. When the birds use a palm tree as "home" the eggs are laid on a palm frond, without the benefit of a nest or any real cover, hence many eggs, as well as young owlets are lost due to windy days and clumsiness of the young owlets. Years ago, it was not uncommon for Fresno Wildlife Rehabilitation Service to have to care for as many as 200 Barn Owl "orphans" in one spring season and that took a great deal of time and money. (Mice cost at least 50 cents each and the young owlets have a voracious appetite, often consuming 6 or more mice in a 24-hour period).
It was obviously too much for any one or two volunteers, so I started the "Barn Owls in the Classroom" program in Clovis, CA. With the help of U.S. Fish and Wildlife and Calif. State Dept. of Fish and Game, I was able to enlist the help of various teacher volunteers, now in Clovis and Fresno, who agreed to help raise orphaned Barn Owls in the classroom with the ultimate goal of releasing the birds back into the wild. It has been many years since the program began and our success has been amazing.
The teachers and students do a great job and after the young birds are beginning to hop-fly the birds are transferred to large aviaries, some of which are on farmland. After the birds have been acclimated to outdoor temperatures and have had time to condition for flight they are Federally banded and released. The person who has the aviary is responsible for putting food out for the newly released birds so that if the birds are not immediately successful in hunting they may return to the "nest site" and get food. This will continue until the owls have finely honed their hunting skills. If prey species are plentiful the young birds will inhabit the area and may, the next spring, set up "housekeeping" in a farmer's Barn Owl nest box. As farmers/ranchers/growers began to install Barn Owl nest boxes all over the valley, we have seen a real decline in the orphan population each year. That is such a good thing. The next boxes are so much safer for the owlets, if the boxes are made properly and installed correctly, the birds have a much better chance of surviving all the way to fledging the nest. These same fledglings hopefully will find enough gophers, mice, voles, etc. that they will continue to hang around your farm or ranch and assist you in your efforts to reduce rodent-caused damage to your vines.
Want more owls on your property? You can also try calling your local wildlife rehabilitation service and find out if you might be able to build a flight cage/aviary for Barn Owls on your farm. The rehab might need additional exercise/conditioning caging for the young birds and would be happy to have you help out. We get calls like this all the time. Please feel free to contact me with any questions or comments you may have. I can be reached by E-mail at fresnowildlife@psnw.com (or you can call me at 559-298-3276, but please understand that I need a night time phone number for you because I work can not return many calls until evening).