Screech Owl Facts

Red phase screech owl in residence in our nest box design

  • The screech owl does not really screech. Its main calls are a soft tremolo and a whinny. The western screech owl call sounds like a bouncing ball.
  • Screech owls are easily attracted to nest boxes.
  • Screech owls eat mainly rodents.
  • Eastern and Western Screech Owl ranges combine to cover most of the U.S.
  • Preferred screech owl habitat is broken woods, gardens, and backyards.
  • Screech owls can easily be called down for observation by imitating screech owl calls or playing recordings of screech owls.
  • Screech owls are common in suburban settings, even within heavily populated areas.
  • Eastern screech owls can be red or gray, even in the same brood.
  • Western screech owls come in brown and gray phases.
  • The rotomolded Screech Owl Nest Box made by the Barn Owl Box Company will far outlast wooden nest boxes.
  • The lack of suitable nesting sites is often the greatest limiting factor for screech owl populations.
  • Screech owls prefer nest boxes over natural cavities, mainly because most natural cavities are more cramped than manmade boxes.
  • Neither Eastern or Western screech owls migrate, remaining permanent residents.

Kestrel Facts

kestrel

  • Combine day-hunting kestrels with nocturnal-hunting barn owls to hit rodent populations around the clock.
  • During breeding season, a kestrel family can consume upwards of 500 voles or mice, and a large number of injurious insects including grasshoppers and locusts.
  • Numerous farmers of various crops have been erecting kestrel boxes for decades.
    An added benefit is simply having these beautiful, acrobatic hunters around.
  • The kestrel does not build a nest but instead relies on taking over crevices, hollows in trees, and the nests of other birds. This makes it easy to attract them to nest boxes.
  • The lack of suitable nesting sites is often the greatest limiting factor for kestrel populations.
  • Kestrels prefer nest boxes over natural cavities, mainly because most natural cavities are more cramped than manmade boxes.
  • The kestrel is an inhabitant of open fields, croplands, and orchards.
  • Once widely known as “the sparrow hawk”, the name kestrel is now more commonly used.
  • Although kestrels generally migrate southward in the winter, they return to their previous territories and nest sites year after year.
  • Females tend to winter farther south than males.
  • A kestrel family will eat upwards of 500 voles or mice per year as well as numerous grasshoppers and locusts.
  • Kestrels generally begin breeding in early April or May, but often breeding activity reaches its peak in early June.

Barn Owl Biology Facts

  • The seventeen species of barn owls are so different than from all the other 200-plus owls in the world that they are placed in their own taxonomic division. This difference is manifested not only in the physiology of barn owls, but also in their behavior. Barn owl species are far more tolerant of man, far more attracted to man-made dwellings, far less territorial, and have much larger broods than most other species of owls.
  • Barn owls are so tolerant of other barn owls that they will often form colonies. An abandoned steel mill in Utah was discovered to harbor over 30 barn owls that hunted the surrounding area. A single barn in central Florida was recently found to contain 10 pairs of barn owls, all of them raising chicks. It was estimated that these 10 pairs and their young harvested between 15,000 and 25,000 cotton rats from the surrounding sugar cane fields annually.
  • Although barn owls tend to breed in the early spring, they have been recorded breeding in every month of the year, even in states as far north as Pennsylvania. Not only is this unusual behavior for other owls, it is unusual for birds of any kind.
  • Other names for the barn owl are Ghost Owl, White Owl, Night Owl, Hissing Owl, Monkey-faced Owl, Church Owl, Death Owl, Rat Owl, Demon Owl, and Golden Owl.
  • Barn owls are the most widespread owl and one of the most widespread land birds in the world. They exist on every continent except Antarctica, and even inhabit many island chains where they have morphed into many subspecies.
  • The barn owl is highly adaptive to prey availability. In Spain the barn owl hunts mostly house mice. In Austria they have been known to take bats. In some areas of the midwestern United States they have taken good numbers of red-winged blackbirds. And on a few occasions, they have even been observed successfully catching fish.
  • Recent research shows that young barn owls in the northern states disperse dramatically in the fall. In fact, some birds have flown as far as 1200 miles. But barn owls have traditionally been thought of as sedentary species, having been seen in winter by farmers around in barns going back for decades. It turns out that the young do disperse before their first winter, but it is the adults, who own good territory, that tend to stay.
  • Despite standing over a foot tall with a three-foot wingspan, barn owls weigh only about a pound. This low ratio of weight to wing size allows the barn owl to fly slowly and deliberately over fields while it searches by sight and sound for its prey below.
  • Spearheaded by the University of Tel Aviv, Israel has one of the most robust barn owl nest box projects in the world. Communal farms have reported such success with erecting hundreds of nest boxes around the country that Israel’s Ministry of Agriculture has decided to fund and expand the project.
  • Barn owls can hear so well that researchers believe they can distinguish which species of rodents they are hearing from the sounds the rodents make as they run along the ground. In one study, it was found that barn owls were capturing pregnant voles at a much higher ratio than existed in the population, showing that they were selecting the fatter voles over the others—most likely through their keen auditory senses.
  • “For the pocket gopher… barn owls…can represent a substantial biological control that can be manipulated with the placement of barn owl nest boxes around and in the orchard. Research work in California examined contents of barn owl nest boxes in the San Joaquin and Sacramento Valley around prunes, vines and pecans. Results showed pocket gophers represented over 50 percent of the barn owl diet representing an average of 215 gophers ‘taken’ during the breeding and nestling phase….” California Fish and Wildlife Service

California State Fair

California-State-Fair-LogoSince Mark Browning delivered three days of talks on barn owls at the California State Fair in 2011, a sample nest box has stood on the grounds in the agricultural section.

 

Post Gazette Reports Satellites Will Keep An Eye On Barn Owls

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Photo by Bill Wade, Post-Gazette

The Pittsburgh Zoo and PPG Aquarium’s barn owl program has seven babies and two adults being raised at a private Fox Chapel location. They will be released into the wild with transmitters

Sixteen barn owls that were bred in captivity will be carrying some baggage when they are released into the wild tomorrow.

For the first time, transmitter harnesses will be put on the birds so that satellites can track them.

“That gives us a really good chance to find out where they’re going,” said Mark Browning, animal trainer and head of the barn owl release project at the Pittsburgh Zoo and PPG Aquarium.

Eight of the 11 birds that the zoo will release in Fox Chapel tomorrow will carry trackers. The Moraine Preservation Fund will put devices on another eight birds that will be released from Moraine State Park.

The project is part of an effort to re-establish barn owl populations in Western Pennsylvania. Partly because they’re nocturnal, it’s hard to tell how many of them are in the region.

According to director Heather Cuyler Jerry, the preservation fund has released about 250 birds in the last seven years, but doesn’t have much information about how they’ve fared since they were released from captivity.

Data from the satellite telemetry project, which was partly funded by a grant from the Pittsburgh Foundation, could help shape the barn owl program in coming years by revealing favored nesting areas, she said.

The trackers “will transmit for about nine months and give us an opportunity to see what kind of territory they [barn owls] reject and what kind of territory they accept,” Browning said.

Dan Brauning, wildlife diversity supervisor for the state game commission, was excited to hear about the project.

“They’re doing satellite telemetry? Wow!” he said. “From a research standpoint, it’s absolutely the right thing to do.”

Browning said the harness is an intricate sling of Teflon ribbons that, like a parachute harness, wraps around above and below the bird’s wing and meets at the back. A fine antenna curves behind the bird, where it should not hinder normal activities.

When it was first put on, the equipment was easy to spot. The transmitter is about 2.5 inches long and weighs a little more than half an ounce.

Now, “all you see is the antenna because they’ve been systematically preening everything in,” Browning said. “So now they’re cool and everything is hidden.”

He is working with Frank Ammer, a DNA specialist at Frostburg State University in Maryland to collect blood samples from owls that are about to be released.

So, “if we eventually go out there and find a nest of baby birds and take blood from one of them, we may be able to tell if it’s related to one of ours,” Browning said.

Barn owls were probably a rare bird when pioneers first came to a heavily forested Pennsylvania.

The numbers likely increased dramatically because people “cleared the fields where barn owls like to hunt, they probably created higher populations of rodents and they built beautiful wooden barns where barn owls could nest easily,” Browning said.

But the few barns that are built now tend to be metal prefab buildings that owls can’t call home, and the population has dwindled.

Conservationists like Browning would like to see the population grow and, to help boost it, they have not only bred baby owls for release into the wild, but also provided them with nest boxes to live in.

A good nest box, Browning explained, is about 30 inches long, more than a foot high and about 2 feet deep. That should be enough room for the parents and a clutch of about a half-dozen babies. Barn owls can be nearly 2 feet tall.

“As tall as they are and as big as they look, they only weigh about 1 pound,” he noted. “They’re a lot of fluff.”

The zoo has three breeding pairs. One is kept at the Highland Park facility, in a newly built exhibit near the Kid’s Kingdom. Another pair is housed by the National Aviary on the North Side.

A third duo and their seven young, about 90 days old, are kept at a specially built flight on a large private property in Fox Chapel. Four other young owls that were born last fall will also be released from the site.

The open-air cage is partitioned so that when it’s time to let the youngsters go, their breeding pair can still be confined. Boxes for nesting and roosting look the same as those being distributed in the wild to help the owls recognize them as a safe haven.

Since their births, the young owls have been fed frozen mice that have been thawed. But in the days before their release, they must hone their flying, swooping and hunting skills to catch live mice that will be placed in their cage.

Barn owls have a facial disc that is concave and their ears are assymetrical, making their hearing acute enough to pick up mice pitter-pattering across the ground, Browning said.

When the young owls are better hunters, the cage will be left open so they can leave as they wish.

“If they want to fly out and want to come back, they can do that for a week or so,” Browning said. “At some point, I’m going to decide none are coming back or it’s time to close it up and let them go.”

Photo by Bill Wade, Post-Gazette

Mark Browning, animal trainer and head of the barn owl release project at the Pittsburgh Zoo and PPG Aquarium.

Welcome to our New Site

barn-owl-1This site is designed to help you understand barn owl biology, how to attract barn owls, how best to apply integrated pest management methods for natural rodent control, and give you information on the biology of common pest species, including pocket gophers, voles, mice, and rats. Our Barn Owl Status page includes a state by state analysis of barn owl populations. Also, look for links to articles on using barn owls for rodent control in vineyards, sugar cane, orchards, crop farms, and dairy farms.

In the orchards and vineyards of California, dairy and crop farms of the Midwest, sugar cane fields of Australia, oil palm plantations of South East Asia, and the communal farms of Israel, the barn owl has proved to be a valuable asset in integrated pest management programs, sustainable agriculture, and organic farming. Join those who are using barn owls for natural rodent control and lower crop losses while reducing the amount of poisons entering the ecosystem. At the same time, help aid the conservation of this beautiful bird.

Barn Owls Contribute to Rodent Control

Barn owls have been contributing to rodent control long before the term integrated pest management was born. Since humans planted crops and built shelters, barn owls have lived in close proximity to us. In recent years, using barn owls for pest management has become much more sophisticated. Farms have been able to establish densities of up to one pair for every 20 acres or less, creating an efficient rodent killing system that is self perpetuating.

The reasons that barn owls can be used in this way have to do with the unique nature of barn owl biology:

  • Barn owls are cavity nesters, dependent upon large hollow trees or some other type of hollow. This means that they can be easily attracted to nest boxes.
  • Barn owls live and raise young comfortably around human activity such as busy farmyards and agricultural fields
  • Barn owls are not territorial; they often form nesting colonies in small areas, allowing farmers to establish many nest boxes within sight of each other
  • Barn owls raise large numbers of young for a raptor—up to 13 young have been recorded in one nest, although 4 to 7 is more common
  • Seven-young-in-a-single-boxBarn owls respond to higher rodent numbers by producing more young per brood, and producing more than one brood per year.
  • Because they have such voracious appetites and have so many young, a single family of barn owls can consume over 1000 pocket gophers per year, or over 3000 mice or voles.
  • Barn owls are extremely faithful to their nest sites, raising young year after year; and as older barn owls perish, new ones take their places.
  • Once established, barn owls need very little maintenance, and can create a population that remains for many years.

Integrated pest management takes a broad, multi-disciplined approach to rodent control. Barn owls can assist natural rodent control programs by harvesting large numbers of rodents throughout the year. This allows other approaches such as trapping and the use of buffer zones to be more effective.