March 2020

Photo © Jill Lang | Dreamstime.com

Whooo Gives a Hoot?

Texas' 17 species of owls provide nocturnal pest control.

by Cliff Shackelford

Who gives a hoot about owls?
For me, they’re special.

I once wooed a fellow biologist by taking her on an owl prowl to see screech and barred owls. My success must have impressed her, since we’ve been married for more than 20 years.

Apparently, I’m not the only one who loves owls. In a recent national study, researchers found that owls, more than any other group of birds, were the “subject of public curiosity.” Owls are a frequent topic for questions called in to my live radio show on birds.

We hear owl sayings all the time, such as “wise old owl” or “night owl.” Remember Woodsy Owl? The U.S. Forest Service’s mascot gave us the 1970s slogan, “Give a hoot, don’t pollute!”

Owls also serve as mascots, including both Rice and Temple universities, high-IQ society Mensa and sorority Chi Omega. An owl was the companion animal for Athena, the Greek goddess of wisdom. A picture of an owl can be seen in ancient Egyptian hieroglyphics for the sound “m.” More recently, owls were used as couriers in the Harry Potter books and movies.

In some cultures, owls are associated with evil and sorcery, likely due to their nocturnal habits. Some Native Americans refuse to look at an owl because they believe it carries their elders’ spirits. In Romanian culture, the call of an owl means that someone’s going to die. Aztecs and Mayans also considered the owl a symbol of death and destruction and used the phrase “when an owl cries, someone dies.” In Finland, the owl is viewed paradoxically as both wise and dimwitted (for its perceived “dumb stare” when spotted by an observer). In India, a white owl is a sign of wealth and prosperity.

There are approximately 225 species of owls, and they occur on every continent except Antarctica. Oddly named owls include the laughing owl of New Zealand (extinct 1914), the powerful owl of Australia, the barking owl of Australia and New Guinea, the fearful owl of the Solomon Islands, the morepork owl of Tasmania and New Zealand, and the Sumba boobook owl from Sumba Island of eastern Indonesia.

With all the superstition surrounding owls, what’s actually so special about them? For starters, they are nature’s pest control for rodents and insects. They’re also fun to watch. Most owls are nocturnal (active at night) or crepuscular (active at twilight), while very few are chiefly diurnal (active during the day).

There are many threats to owls: conversion of native habitat, poisoning by pesticides, flying into utility lines, getting hit along our roadways, and loss of mature trees (or dead trees with cavities) used for nesting by some species.

Speaking of nests, owls aren’t engineers. None construct a nest but instead use old cavities, rock ledges, scrapes on the ground, abandoned stick nests used by other large birds, and other creative sites. Typically, females incubate at the nest site while the males find food for them. (Perhaps females get this treatment because, in most species of owls, the females are 10 to 15 percent larger than their mates.)

Owls have facial discs and asymmetrically placed ears that receive different “readings” of sound, called triangulation, to assist in pinpointing the sound’s exact location, possibly a tasty rodent. By design, owls are silent in flight, thanks to velvety feathers that absorb flight sounds, allowing them to sneak up on skittish prey.

Speaking of prey, owls have a predatory diet that includes invertebrates like wood roaches and other insects, spiders, crabs, snails, earthworms and scorpions, plus vertebrates like fish, amphibians, reptiles, mammals and birds. Since owls take big, gulping bites or swallow prey whole, they regurgitate pellets of indigestible items like bones, hair, hard exoskeletons and feathers.

Texas has 17 documented species of owls: 12 regularly occurring and five others so unusual they require proper proof (photograph or sound recording) for verification. Those rare five include the northern pygmy-owl, northern saw-whet owl, mottled owl, stygian owl and snowy owl.