On the Brink: Burrowing Owls Find Sanctuary

Charismatic and adorable, burrowing owls are a precious sight. Incredibly charming, these tiny, long-legged birds are roughly the weight of an apple and not much bigger than a robin. Cowboys once christened them “howdy birds” because they bob and nod in front of their burrows. Sadly, they are much more rare than they were back in the days of the open plains and, despite their friendly reputation, it’s important that humans steer clear of their nesting sites.

Their breeding season lasts from February to August and it’s a particularly harrowing time for these brown-mottled birds. Because of many threats — from predation to dwindling habitat — just 25% of their young will survive their first winter. Despite these disheartening odds, burrowing owls deserve a fighting chance to survive.

Sandra Menzel is an avian ecologist and an experienced burrowing owl biologist. In this video, she shares about the ongoing local efforts to bring the species back from the brink.

A POPULATION LONG IN DECLINE

The sobering truth about burrowing owls is that they’re increasingly rare in our region. Back in 1979, California designated them a Bird Species of Special Concern. By the late 1980s, about 500 burrowing owls frequented 250 breeding locations across Santa Clara County. With the tech boom well underway, a rapidly growing human population caused urban areas to expand and suitable grassland habitat to shrink.

Over 30 years later, the circumstances are significantly more dire. We’re now down to just four breeding locations and about 40 adult burrowing owls. These creatures predominantly dwell in what is now the urban area of Northern Santa Clara County. Due to construction, aircraft and other human disturbances, the remaining breeding locations are far from ideal.

PROMISING EARLY RESULTS

The good news is that, with funding from the Santa Clara Valley Habitat Agency, Talon Ecological Research Group is conducting a project that aims to give burrowing owls safe, private places to nest! POST and the Santa Clara Valley Open Space Authority are supporting the effort by providing land. After spending time at a captive breeding center while their future homes were being prepared, several burrowing owl pairs now inhabit a portion of POST-protected property in a rural part of Santa Clara County. As of late spring, researchers had counted nearly 40 eggs and a hatchling. We’re thrilled (and cautiously optimistic) about this promising development!

We’re hardly out of the woods yet, though. Curious human visitors easily unsettle burrowing owls. It’s critical that people keep their distance from the birds — and other wildlife in general — so as not to spook them or disturb their habitat. Despite best intentions, if adult owls feel unsafe when birders approach, they might even abandon their nests. It’s a grave risk we’re unwilling to take.

DIGGING DEEPER INTO BURROWING OWL BEHAVIOR

Burrowing Owls & Ground Squirrels: A Match Made in Heaven

Did you know that, of the 140 species of owls in the world, burrowing owls are the only ones who roost and nest underground? Curiously enough, these enterprising birds don’t dig their own dwellings. Instead, they inhabit the empty burrows of neighboring animals who spend most of their time underground. In the Bay Area, they rely on a familiar expert excavator: the California ground squirrel.

The pair share many natural predators including coyotes, foxes, bobcats, badgers, hawks and snakes. This means the two species can look out for each other. Remarkably, they recognize one another’s warning calls when a predator’s nearby, enabling both to hide underground until the coast clears. Because ground squirrels far outnumber burrowing owls, they help reduce the bird’s risk of predation.

5 Fascinating Facts

Looking to learn more? Here are five fun things to know about these amazing owls:

• Burrowing owls don’t hoot. Occasionally, the birds coo, warble, rasp, cluck and even scream. When cornered, young owls produce a call that mimics a rattlesnake’s signature sound.
• They collect objects to decorate their burrow entrances! Their treasures include everything from bottle caps to feathers to soy sauce packets.
• Each female burrowing owl can lay up to 12 eggs in a season.
• You can’t tell the difference between male and female burrowing owls in winter because their coloration is identical. In the breeding season, however, males spend more time above ground in the daytime, guarding their burrows and hunting for food for their offspring and mates. As a result, they may have lighter plumage than their female counterparts.
• Some burrowing owls have a fascinating (albeit smelly) approach to home decor. They adorn the entrances to their burrows with dung from a variety of species, such as geese, cows or dogs. Scientists speculate that they aim to lure prey (like dung beetles and other insects) to their homes. Another hypothesis: they’re trying to cover up their scent to throw off their many predators.