10 Facts About Elf Owls, the Smallest Owls in the World

Elf owls are true owls, members of the Strigidae family. No larger than a sparrow and weighing about as much as a golf ball, these dainty birds are stealthy hunters. Found nestled in recycled woodpecker holes in the deserts and canyons of the southwestern U.S. and Mexico, elf owls favor insects and invertebrates, which they hunt on foot and by air. They fend off potential predators with a variety of loud vocalizations that make them sound larger than they are. These petite birds of prey are endangered in California.

From their intriguing courtship songs to their ability to play dead, here are a few things you might not know about the elf owl.

1. Elf Owls Are Really Small

Also known as Whitney’s Owl, and their scientific name of Micrathene whitneyi, elf owls — the world’s smallest owls — are extremely petite. Adult elf owls reach a length of only 5 inches – the size of a songbird – and their wingspan is just 9 inches long. They are also extremely light, weighing in at under 2 ounces. Female elf owls are slightly larger than males.

2. They Recycle Woodpecker Holes

The favorite nesting spot for elf owls is in old woodpecker holes in saguaro cactus, mesquite, sycamore, and oak trees. When a former woodpecker home isn’t available, they’ll choose a manmade structure like a telephone pole or a nest box. They prefer to nest up high, from 10 to 30 feet off the ground, where predators like snakes, bobcats, and coyotes are less likely to get to them.

3. They Love to Eat Insects

While the larger members of the owl family eat small mammals, elf owls are agile hunters of insects such as moths, beetles, and crickets, but they also prey on scorpions, spiders, and katydids. They are also quite flexible, adjusting their food choices with the weather. During the dry season in Arizona, they feed primarily on moths and crickets; when the summer rains begin, they hunt instead for beetles, which are more plentiful.

Since water is not always available in their desert habitat, elf owls are able to survive on the water they get from the creatures they eat.

4. They Are Skilled Hunter-Gatherers

Aided by excellent vision and hearing, elf owls are skilled nocturnal foragers that catch their prey in flight, on the ground, or within the trees. They patiently wait at their perch and grab their intended target with their feet or beak. If they capture more than they need, they'll store the extra food in their nesting hole for later. When their prey is a scorpion, the ever-cautious elf owl will remove a scorpion's stinger before digging in or feeding the catch to their young.

5. They Sometimes Migrate

Because they rely on insects that are less available during cool winter nights, elf owls are one of the few owl species to migrate (flammulated owls and snowy owls also migrate when food becomes scarce). Found in the deserts and canyons of Arizona; New Mexico; Texas; Baja, California; and Sonora, Mexico, migratory elf owl populations breed near the U.S. border with Mexico and head south to southern Mexico for the winter. Elf owls occasionally migrate in flocks. The populations farther south, in Baja, California, and Puebla, Mexico, stay put year-round.

6. They Woo Mates With Nests and Song

During mating season, males woo females by singing loudly from within their nest holes, luring would-be partners to check out their digs. They have a special song reserved for mating purposes, which they sing nonstop from inside the nest until a female follows them inside. To further entice a female, the male elf owl will offer her food as part of the courtship ritual.

7. They Are Mostly Monogamous

While some elf owl pairs mate for life, for others, monogamy only lasts for one breeding season. After mating, the female elf owl lays up to five eggs. She is the sole incubator, but the male brings food to the female while she’s caring for the eggs and for the first couple of weeks after the owlets are born. After that brief period, the female also leaves the nest to hunt for food. About a month after hatching, the owlets are fledging and the parents sometimes refrain from bringing them food to encourage them to leave the nest and fly out in search of food on their own.

8. They Can Put on an Act

Elf owls have a few clever methods for dealing with predators. When an intruder is near their nesting site, elf owls make a loud barking sound, clap their bills, and quickly move their tails back and forth. And, unlike larger owls who wouldn't think of backing down in a fight, when the elf owl is captured or cornered, it plays dead.

9. They Are in Decline

While they are not considered threatened by the IUCN, the elf owl population has declined due to habitat loss caused by residential and agricultural development. Populations in southern Texas and parts of the Colorado River have been particularly affected, although the owls are still found in large numbers in Arizona. In California, the owls have been endangered since 1980. Due to damage to the owls’ habitat, efforts to reintroduce the species have not been successful.

10. Their Hoot Is a Hoot

Elf owls have calls that are as adorable as they are. Adult owl calls have been compared to the sound of a puppy dog or laughter. Males have distinct songs for flight, while females make a special sound when they are being fed by a mate. During nesting, both males and females communicate with a soft whistling sound to their babies and each other. Baby owlets make soft peeps or squeaks to get their parents’ attention, raising their volume and rate of vocalizations with their level of hunger.