Chasing the call: Tracking the secret lives of burrowing owls across the West

At dusk on a lonely South Dakota byway Anthony Locatelli saw the flit of a bird’s wing at the edge of his headlights.

He pulled his pickup over to the road’s edge, got out and after the engine had quit and the night noises resumed in the vast Western plains, he set up a speaker and played a recording of an owl call.

There was a reply. It was a call Locatelli knew well.

The return chirp was from a Western burrowing owl likely perched out of sight on a rock or fencepost in the looming darkness. It was an individual the U of I doctoral student didn’t have in his vast log of owls that lived in the region.

So, he noted the encounter and decided to return the next morning to catch a glimpse of the owl, try to capture it and outfit it with a radio collar.

As part of his work to earn a doctorate degree in the Idaho Cooperative Fish and Wildlife Research Unit lab of Professor Courtney Conway, Locatelli has been crisscrossing the Western U.S.A. from the Southwest to the high desert regions of Oregon and east to the Dakotas to learn more about burrowing owls.

Western burrowing owls have disappeared from many portions of their historic breeding range, and their population is decreasing, Locatelli said.

The decline of burrowing owl populations is often attributed to the conversion of native grasslands to agriculture and urban development, and to less abundant burrowing mammals that the owls rely on for the creation of nest burrows.

Although burrowing owls — so named because they refurbish the abandoned dens of mammals such as skunks, gophers, ground squirrels and even tortoises to make nests where they lay eggs and raise their young — are relatively well studied during the breeding season, while little is known about their ecology after breeding.

Locatelli’s research explores why some burrowing owls move to a distinct post-breeding home range where they spend approximately 10 weeks before their annual fall migration while others do not.

Locatelli is among researchers across western North America to attach satellite transmitters to a combined 280 burrowing owls in the U.S. and Canada over the past 11 years.

“It enables us to document movements and habitat selection of burrowing owls after they leave the breeding grounds,” he said.

During the summer, he drives thousands of miles crisscrossing the Western plains from the Dakotas to Oregon and south almost to Mexico to catch, watch and collect data on burrowing owls.

“Driving a lot of miles on these remote backroads is just something you do as a wildlife biologist; it’s kind of cool,” he said.

He catches owls by locating their dens, placing a live trap inside outfitted with a recording device that mimics another owl. When the owls enter the den to meet a fake adversary, they are caught in the trap.

The transmitters he attaches to the owls allow researchers like Locatelli to document daily survival across the burrowing owl’s annual cycle, including migration and seasonal home ranges.

As part of his research, Locatelli wants to thoroughly describe post-breeding movements of migrating burrowing owls and he wants to document the resources such as food and habitat that burrowing owls select during migration.

All of these factors influence the bird’s survival, he said.

“The results of this project will help ensure management efforts that target burrowing owls do not neglect to consider post-breeding and migration life stages where knowledge is currently lacking,” he said.