The Sonoran desert of southern Arizona is famous for its towering saguaro cacti, some reaching 40 feet high. These giants aren’t just plants. They are high-rise apartments for elf owls (Micrathene whitneyi). The world’s smallest owl species nests in abandoned woodpecker holes carved into the cactus flesh. The thick walls insulate the owls from extreme heat. The height keeps them safe from ground predators.
These tiny birds weigh between 1 and 2 ounces. That is less than a golf ball. Their feathers are grayish-brown for camouflage. They have large pale yellow eyes and no ear tufts. Long legs help them chase insects on the ground. When perched, they look bowlegged. Like tiny cowboys. Their calls sound like a puppy yipping.
Silent Hunters in the Dry Southwest
Elf owls hunt at dusk and during the night. They eat insects and scorpions. They remove the scorpion’s stinger before eating. They get all their water from their prey. No need to search for water in the desert.
Owls are silent killers. Bird wings usually make a gushing sound. Owl wings have projections on the front edge. A fringe of feathers at the back breaks up airflow. Soft feathers on the wings and legs absorb the rest. Prey don’t see them coming. They don’t hear them until it is too late.
Breeding and Migration Patterns
In spring, females lay one to four eggs. They hatch in about three weeks. At first, the father brings food to the mother and chicks. After a few weeks, the mother also hunts. The growing brood needs more food.
When the babies fledge, nights get cooler. Tasty bugs become harder to find. Elf owls move to Mexico and Central America for the winter. They prefer to flee than fight. But they will mob predators. If a great horned owl appears, elf owls dive-bomb it. They make loud alarm calls. Other birds join in. Sometimes different species team up. The great horned owl’s chance of a meal drops sharply. If a predator gets close, an elf owl plays dead. It stays still until the danger passes.
The Slow Growth of Saguaro Homes
It takes 10 years for a saguaro to grow 1 inch. By age 70, it produces its first flowers. By age 100, it may produce its first arm. Some saguaros have dozens of arms. Some have none. The reason is unknown. These cacti provide the essential structure for elf owl survival.
The survival of these smallest owls depends on the slowest growing cacti. If one declines, the other suffers.
