Science Corner - Burrowing Owls

Kristie Ehrhardt • August 6, 2025

Do you remember the Haunted Forest in the Wizard of Oz? Most of us probably envision owls as those shadowy birds with the glowing eyes skulking at Dorothy and the gang from the dark tree canopy. True, most owls are nighttime creatures, and they do have large round eyes, but they certainly don’t glow like a red-hot cigarette lighter in a 1985 Oldsmobile. And yes, most species of common owls do roost in trees but, did you know that we have a very special little owl in our region that is active during the day as well as the night and nests and roots in underground burrows?! I realize that the name kind of gives it away but if you guessed Burrowing Owls, pat yourself on the back!

 

Burrowing Owls (Athene cunicularia) are a small species of owl that belong to the family Strigidae, the same family that includes other owls in our region including Great-horned Owls, Screech Owls and the eared owls. The name Athene comes from the Greek goddess of wisdom and cunicularia translates from Latin to mean miner or burrower - quite literally meaning “wise burrower”.

 

Burrowing Owls are fairly social and although they usually only have one mate at a time, they tend to nest and live in loose colonies. Males and females look alike however males are often lighter in color from sun bleaching as they spend more time outdoors while the females remain underground with the young. Both sexes average between seven and 11 inches long with wingspans of about 20-24 inches. They weigh five to eight ounces with females weighing slightly more than males. Both males and females lack ear tufts and have a flattened facial disk with prominent white eyebrows. Their large eyes are bright yellow, and their beaks are dark yellow to gray. Their heads, backs and wings are sandy brown with white mottling, and their abdomens and chests are a buffy brownish-gray with white barring. Juveniles look similar but lack the white mottling or barring. If you ask me, one of their most endearing physical traits are their long legs. Burrowing Owls prefer open areas and their lengthy legs allow them to perch on the ground and still keep watch over their surroundings. When disturbed, or even if they think they might be disturbed, agitated owls will bob up and down while chirping and giving whatever they’re perceiving as a threat the death stare. If that isn’t enough to intimidate the presumed threat, the owl will simply fly off. Another fascinating behavior is Burrowing Owls’ love of decor. They will collect things they find interesting and decorate the entrance of their burrow. These items often include flower petals, shiny things such as bottle caps, bits of beetle exoskeleton, and small rocks. Sometimes Burrowing Owls will collect scat from larger animals which in turn attracts dung beetles that become a “door dash” snack delivery for the owls.

 

Being active during both the day and night hours helps the owls to secure different food sources; prey species include insects, amphibians and small lizards during the day and small mammals at night.

 

There are several subspecies of Burrowing owls but the genus as a whole has historically occurred from southwestern Canada, the western United States (minus the humid Pacific Northwest) into Mexico and east into Florida, in Central America, some Caribbean Islands and in most of South America. Most populations of Burrowing Owls do not migrate but those that occupy the northern end of their range may migrate seasonally to avoid the cold winter months (I would too!). Their habitat preferences include open or grazed areas with shorter vegetation such as dry pastures, prairies, open grasslands, savannas with an established burrowing mammal population to provide underground nesting locations for the owls. Burrowing Owls are extremely adaptable and have also occupied urban areas such as airports, golf courses, grassy areas in highway interchanges, parks, schools, parking lots and even landfills and other other relatively undisturbed urban and suburban areas. Most individuals do not excavate their own burrows but rather take over abandoned mammal burrows including those dug by ground squirrels, prairie dogs and badgers. Some populations and subspecies will dig their own burrows or enhance those made by other species if the soil is not rocky or compact. Burrowing Owls have been documented utilizing man-made burrows as well.

 

The subspecies found in our region is the Western Burrowing Owl (Athene cunicularia hypugaea). Once widely disturbed across California, habitat loss as a result of urbanization, ground squirrel population decline, pesticide use, predation from coyotes, foxes, badgers, feral cats and changes in land use practices have resulted in drastic population declines since the 1980’s. Several attempts have been made to give the Western Burrowing Owl protection as a special-status species, however, as of yet it has not been afforded any official lasting protection.

 

If you’ve had the pleasure of observing burrowing owls you know exactly how charismatic they can be. If you haven’t seen them do keep your eyes open for them, you’ll be glad you did!


-Kristie Ehrhardt (kehrhardt@tuleyome.org)

Tuleyome Land Conservation Program Manager

RECENT ARTICLES

Policy Corner: The San Pablo Bay National Wildlife Refuge Expansion Act

By Diego Barraza • December 3, 2025
In October, Tuleyome hosted a community walking tour showcasing Mare Island’s southwestern coastal wetlands, a notable potion of the six distinct parcels proposed to be included in The San Pablo Bay National Wildlife Refuge Expansion Act. By law, National Wildlife Refuges overseen by U.S. Fish and Wildlife Service (USFWS), are legally mandated to conserve migratory bird and endangered species habitat while allowing for public access and recreation compatible with those mandates. This boundary expansion legislation is expected to be introduced in the 119 th Congress by Representative John Garamendi (D-CA-08), Jared Huffman (D-CA-02) and Mike Thompson (D-CA-04) and Senator Alex Padilla (D-CA). Approximately 6,934 new acres would be included in the boundary expansion. The boundary expansion aims to enhance the existing refuge’s 24,390 acres of essential wetland habitats along the coastlines of Sonoma, Solano, and Napa Counties. These tidal marshes, mud flats, and seasonal wetlands all host migratory birds, small mammals, and form the nursery grounds to sensitive fish species. Some iconic species include the California clapper rail, salt marsh harvest mouse, San Pablo song sparrow, and Suisun shrew. Current owners of the parcels that are proposed to be included within the refuge boundaries are the State Lands Commission, the State Coastal Conservancy, and the Sonoma Land Trust, all who support the proposal.

Monumental Questions - The United States Endangered Species Act

By Kristie Ehrhardt • December 3, 2025
You may have heard that there are some modifications brewing regarding the protections afforded species by the United States Endangered Species Act (ESA). Often regarded as one of the most powerful and effective (as well as sometimes controversial) environmental laws in the United States, the ESA was written into law with bipartisan support on December 28, 1973. The purpose of the ESA was to provide the infrastructure to conserve species and their habitats here in the United States and elsewhere. To date 99% of the species listed under the ESA have avoided becoming extinct. Under the law, organizations as well as individuals can petition to have a species listed as threatened or endangered under the ESA. The petitions then undergo extensive evaluation and review by scientists and the public prior to a decision being made about whether the species in question should be listed under the ESA. The ESA also requires that critical habitat areas also be protected as well as recovery plans be drafted for the species. Although this sounds very rigid, the law does allow for flexibility and requires coordination between federal, state, tribal and local agencies to conserve and protect species and their habitat. As the ESA currently stands, once a species is listed as threatened or endangered under the ESA, it and its habitat is afforded formal protection. Any impacts to the species itself or its habitat will likely require a permit and possibly remediation from the United States Fish and Wildlife Service or other leading agency. Under the required recovery plans, populations are monitored over several years to determine if efforts being made are aiding to its recovery. Once a species is considered recovered, it is removed from the special-status species list. Admittedly it is a long process but it is successful. One of the most illustrious delisting is that of the Bald Eagle ( Haliaectus leucocephalus ) in 2007 following the banning of dichlorodiphenyltrichloroethane (DDT) and a recovery period for the eagles. Another celebrated species that has been delisted from the ESA is the American Peregrine Falcon ( Falco peregrinus ) in 1999 following a captive breeding program and other intense conservation efforts. In 2016, more species were removed from the special-status species list than ever before. The other way that species can be removed from the special-status species list is if the decline has become irreversible and they are unfortunately classified as extinct. Habitat loss, overuse, competition from invasive non-native species and disease introduction are often human-caused and can be reversible if caught early enough. The goal of the ESA is to strengthen and highlight conservation efforts for species and their associated habitats. In addition to the ESA, the United States also works in cooperation with Migratory Bird Treaties with Canada, Mexico and Japan as well as the Convention on Nature Protection and Wildlife Preservation in the Western Hemisphere, the International Convention for the Northwest Atlantic Fisheries, the International Convention for the High Seas Fisheries of the North Pacific Ocean, the Convention on International Trade in Endangered Species of Wild Fauna and Flora and other international agreements. The ESA also offers assistance to states and other associated parties to develop and utilize conservation programs that meet national and international conservation standards for the best interest of the US citizens and our heritage in fish, wildlife and plants. The Berryessa Snow Mountain National Monument is home to several species protected under the ESA including the federally threatened Northern Spotted Owl ( Strix occidentallis caurina ), the federally endangered Pacific Marten ( Martes caurina ) and the Pacific Fisher ( Pekania pennanti ), the federally threatened California Coastal Chinook Salmon ( Oncorhynchus tshawytseha ) and the Northern California Steelhead ( Oncorhynchus mykiss indeas ).  -Kristie Ehrhardt ( kehrhardt@tuleyome.org ) Tuleyome Land Conservation Program Manager

Enjoying Outside! - Wild Turkeys

By Kristie Ehrhardt • December 3, 2025
Urban legend has it that our national symbol was nearly the Wild Turkey. Ben Franklin called them a “bird of courage” and it’s been said that he suggested that the Bald Eagle be replaced with a Wild Turkey. I’m not sure if that is true but I will say that after having a confrontation with the turkey brigade, they are not to be messed with. There are only two species of Wild Turkey world wide; the one we’re familiar with here in North America (Meleagris gallopavo) and the Ocellated Turkey (M. ocellata) found in Central America. For different reasons, the Wild Turkey is probably one of the most recognizable birds in the United States. Although I think they look best foraging under oak trees, some think they look even better on a platter surrounded by all the Thanksgiving accoutrements. Wild Turkeys are upland game birds and belong to the family Galliformes. The domesticated white turkey is a relative of our pretty Wild Turkey. Adult males have featherless red heads, long reddish-yellow legs with three toes facing forward and one rear-facing toe just below a nasty spur that they use to fight other males with. Their body feathers are generally dark brown and black with a stunning coppery sheen and a fan shaped tail. His iridescent feathers have areas of bronze, copper, green, gold, purple and red. Females on the other hand are about half the size of males and in following female upland game bird dress code, are mainly drab brown to camouflage while sitting on the nest. Ironically, this hefty brute that tries to intimate shoppers in the grocery store parking lot or corner toddlers in the neighborhood park was nearly extinct by the 20th century. By the early 1900’s only about 200,000 individuals were left roaming the country-sides of the United States due to habitat loss and over-hunting. Thanks to conservation efforts and responsible hunting practices, today their population is estimated at 6.5 billion wild birds in the United States. While several states have “turkey-rich refuges” here in California it seems that the birds have badgered their way into many of our urban and suburban areas. Wild Turkeys have funny appendages with funny names. The wattle is the skin flap that hangs from the beak to the neck and the snood is the piece of flesh that dangles from the beak. Can you guess what a caruncle is? Naturally, they’re the little bumps of flesh that cover the bird’s necks and heads. And of course we can’t forget about their beards - those are the bundle of stiff feathers that grow from their chests. All males have them and so do a few females but theirs is not nearly as glorious as the males’. The beard gets longer as the bird ages and biologists still don’t know what the purpose they serve. Very young turkeys are called poults and eat insects like they were gummy bears. As they age they develop a more refined and mature pallet and begin to incorporate some vegetation. Adult turkeys eat acorns, nuts, seeds, berries, insects and even small reptiles and amphibians. Young males are called jakes and adult males are called Toms while female turkeys are called hens. Wild Turkeys are highly adaptable and in California they can be found occupying a wide range of habitat types from oak woodlands, to mixed conifer forests, valley riparian, high deserts and even suburban parks and parking lots. You may find them pecking at their reflections in glass office complex doors, strutting around the post office parking lot or sitting on the hood of your car in the driveway. Fun Wild Turkey Facts! Wild Turkeys are much more agile than they appear. They have been clocked at 18 miles per hour on foot and can fly 50 to 60 miles per hour! Wild Turkeys have excellent vision and can see three times better than our perfect 20/20! They can change the color of their heads based on their mood! Although they’ve been called “courageous”, these softies sleep together in trees for safety. Males and female turkeys can be distinguished based on the size and shape of their droppings. Who knew? On average, adult Wild Turkeys have between five and six thousand feathers! When you’re walking off your Thanksgiving meal, keep an eye out for these beauties. Their habitat includes more than just your dinner table!  -Kristie Ehrhardt ( kehrhardt@tuleyome.org ) Tuleyome Land Conservation Program Manager