Riverside Farms Barn Owl Nest Box Project

I am starting a barn owl nest box project to increase the barn owl population in the Riverside California green belt.   The green belt is a  5000 acre voter protected agricultural preserve.      This will allow farmers to reduce the use of rodenticides by utilizing barn owls to remove gophers, rats and other farm pests.   The population will only increase if there is nesting habitat which is old hollow trees or wooden barns which really don't exist in Riverside.    Access to nest boxes will allow the population to increase.   This in an environmentally friendly way to eliminate the use of poisons which kill many predators who may eat a gopher or rat which has ingested poison.   
A pair of barn owls will eat a 1000 gophers or rats during a breeding season .   A pair will raise 4-6 young barn owls which will also need nesting boxes when they mature.
I have used my own funds to purchase 8 nest boxes but need help to increase the number of nest boxes.  I believe the agricultural preserve can support 200-300 nest boxes but a 50 will help increase the population.
Each nest box costs around $200.00 with mounting supplies.    Please sponsor a nest box by donating whatever you can to improve our environment and help farmers reduce losses to pests