Frequently Asked Questions about Using Barn Owls

 for Rodent Control

By Tom Hoffman

 What level of gopher control can I reasonably expect with barn owls?

Barn owls will NOT reduce a rodent problem to zero.  However they can make a dramatic difference in an area with an extreme rodent problem (Sonoma County) and keep it under control. In a mature vineyard, gophers can be reduced to a tolerable level without the use of baiting.

Variables include population density of rodents, population density of barn owls, amount of available nesting places in your vicinity, and the presence of Great Horned Owls in the vicinity.

I have gophers, what do I need to do to attract barn owls?

If you live inside the range of the barn owl,(lower 48 states) simply put up nest boxes.   You can put them up any time, but the nesting season is from February to June.  The rest of the year, the adult owls will use them for roosting during the day and perhaps for perching in the night.

 Will barn owls help with my ground squirrel problem?  No, barn owls will not affect your ground squirrel population because the squirrels are active in the daytime while the owls hunt at night. The Golden Eagle and the Red Tail Hawk are the main predators of the ground squirrel.  Erect several 20 to 25 foot tall perches near the squirrel colony to aid these raptors as they hunt.

Will Barn Owls attack my cats, (or me)?  Although it is doubtful that barn owls will attack a cat for food, it may do so if the cat gets too close to the owl’s nest.  It might also attack you for the same reason if it can do so safely and has the advantage of surprise.  While barn owl attacks on humans are uncommon, they are not unheard of.

 Where do I put the nest boxes? Put them up wherever it is convenient for you.  They can go in trees, on posts in the field or yard, on the wall of a building.  Each site has positive and negative points.  In trees, the owls will receive some protection from the elements, but the young will be exposed to predators.  On a post, the young will be protected from most predators, but the box may get hot during a heat wave.  On a building, whatever is below the box will probably get splattered with fecal matter.

Where should I NOT put the nest boxes? Do not put the boxes above locations where vehicles or equipment is parked. Outside you bedroom window is not a good idea either, because the young owls can compete very noisily each time the adults return to the nest with food. In Great Horned Owl habitat, that is, in heavily wooded, riparian regions, Great Horns are the largest predator of the barn owl.  Place them in the middle of your worst rodent-infested area.  Owls prefer not to hunt in the area of their nesting box so as not to attract the attention of potential predators.  Multiple nest boxes in this vicinity will solve this problem because the hunting areas of the different nes

Will routine farm operations bother the owls? No, regular farm activity will not bother the owls as long as the box or post is not bumped.  In most cases they will remain quietly inside the nest box.

How many nest boxes do I need?   One box will achieve the “warm fuzzy” thing, but will nto control your rodents.  Your goal should be to attract as many nesting pairs of barn owls as your rodent population can support.  Remember that it is nesting pairs that you want to attract.  Each adult will eat one rodent a night, but each chick will eat up to four or five, depending on the size of the chick and the size of the rodent.  Six boxes across fifty acres is a good start.  Figure you enough boxes when 20 to 30 percent are not being used at any time of the year ting pairs will overlap.

 If I put up several nest boxes in the same field, will the owl’s territorial instincts cause conflicts? Barn owls are not considered to be very territorial.  The number of owls you attract is a product of the number of rodents and the number of nest sites they can find in your area. This means that you can erect as many nest boxes as you have space for.  And the more nesting pairs of owls you attract, the more rodents you will get rid of.

What do I do if I find a young owl on the ground? An owlet’s ability to survive on the ground depends on age, and state of health.  A juvenile (feathers are present) who has fallen from a tree has the ability to climb to safety.  A nestling (covered with down) may not.  Owlets fallen from pole boxes obviously cannot climb back up.  Owlets on the ground are there for a reason and should be examined for illness or injury. At times the youngest of the clutch will be forced out of the nest by siblings.  In any case, you local wildlife rehab center should be notified immediately.

 How do I capture a grounded barn owl?Capture can be done, it is not particularly difficult, but I  never recommend handling a barn owl (or any other bird of prey) unless you are experienced. Again, call your local wildlife rehab center for assistance.