I was out in the mews (raptor cages) at feeding time and as I entered the enclosure where Minerva, the barn owl resides, she let out her low raspy call that quickly escalated to a high-pitched whine.

There were visitors on the boardwalk passing by, and they stopped in their tracks and asked, “What was that?”

I laughed and said, “It wasn’t me!”

I explained to them that what they couldn’t see, but what they could hear, was the resident barn owl, Minerva. I further explained that not all owls have the same call and not all owls hoot.

The ghost owl

There’s a lot of superstition surrounding these birds because they seem “ghostly” and because of their shrieks. They truly sound like something in pain in the dead of night. However, it is really a good omen for farmers who find them in their barns.

They have very keen vision and hearing sense unmatched in the family of birds. Barn owls are able to hunt in complete darkness.

I once had a college professor tell me that if barn owls could read, they could read newspapers in total darkness, as well. Their eyes are the same size as humans’ but they are about two times as light sensitive Their brown eyes actually help ease some of that sensitivity.

They can hear low frequency and hit frequency sounds that are far beyond what we can hear. But when it comes to the brain, things get a little complicated.

About 75% of the owl’s brain is dedicated for the senses of sight and sound so that leaves the owls with about 25% of the brain to process the data and make decisions.

Tiny but mighty

Barn owls are about 10 to 15 inches tall, weigh between 1 pound to a pound and half, and with wingspans of 40 to 50 inches.

The reason for these differences is that the females are larger than the males. They are about one-third larger for several reasons; females defend the nest, eggs and owlets. Also, with larger bodies and producing more heat they are able to incubate more efficiently than the males.

Their distinctive long, heart-shaped facial disks have earned these owls the nickname of “monkey-faced owl.”

They have nearly pure-white to dusky chests with small spots, small dark eyes, and make hissing or scream-like vocalizations.

Barn owls are found in agricultural fields, grasslands, and other open areas.

Beside the size differences, there are other subtle differences between males and females.

Females are often a rich brown with the gray being slightly darker and more markings overall.

Males are often light buff or white with barring either light gray or not at all.

Females are usually buff or brown with dark gray or black barring. If the tail is light and has no barring at all, the owl is probably male. They extensively use the same nest site every year and have elaborate courtship rituals - such as courtship flights, calls, and offerings of food - to reestablish their pair bond every spring.

Good for farmers, bad for pests

As their name implies, barn owls commonly nest in barns as well as silos, abandoned buildings and artificial nest boxes. They have also been known to nest in cavities of large dead trees, rock crevices and even burrows in riverbanks.

Because barn owls feed primarily on rodents, they are beneficial to farmers.

An average family of barn owls can consume up to 3,000 rodents (mostly meadow voles) during the course of the breeding season. They will also hunt various kinds of mice, small rats, shrews, young rabbits, and other mammals.

Records show that they will occasionally prey upon small birds, lizards, and insects, but rarely upon frogs or fish. Barn owls hunt at night by flying low over open ground, using vision and hearing to hunt. They possess excellent vision in low light levels, and hearing is so precise that they can strike prey in total darkness.

When I go into the mews here at the center to clean the resident barn owl’s cage or feed her, she will bob her head while weaving back and forth, peering at the me as the intruder that I am and will begin her long drawn-out hiss that quickly becomes an ear-piercing screech.

Protection

When barn owls feel threatened, they will exhibit a behavior called toe dusting. While loudly hissing, they will lean over and swinging their heads from side to side.

Female barn owls have 100% of the responsibility of incubating the eggs and feeding the owlets.

Typically, the females will lay between three and 12 eggs with four being the average number of eggs laid. When prey is plentiful, the barn owl pairs may have two broods.

One of the most interesting videos I have ever seen involved a pair of barn owls raising young. The time lapse showed how throughout one night how many voles and other assorted rodents the male brought back to the female to feed the young.

The narrator explained that while the male was an excellent hunter, he lacked the ability to feed the young and was solely the responsibility of female.

Even after a few weeks, when the female would go out and hunt, she still fed the owlets. Young owlets fledge at about 2 months old and continue to sleep or rest near the nest site.

Education and parenting

At a program, a young man raised his hand to share with me that “dad” owls are like his dad. His dad knew how to bring the food home, but he didn’t know how to put it away or how to feed this young man or his siblings. His comment was, “My mom does all that.” His mother looked smug, and his father didn’t look the least bit embarrassed. Dad nodded and agreed with the young man’s statement, while mom just shook her head.

I didn’t have the heart to tell mom she reminded me of the “toe-dusting” barn owl.

Jeannie Carl is a naturalist at the Carbon County Environmental Education Center in Summit Hill. The center rehabilitates injured animals and educates the public on a variety of wildlife found in the area. For information on the Carbon County Environmental Center, visit www.carboneec.org.