Nevada Fish & Wildlife Office
Pacific Southwest Region

Protecting Burrowing Owls At Construction Sites

Burrowing owl

Burrowing Owl photo by Jeri Krueger/USFWS

About burrowing owls

Burrowing Owls (Athene cunicularia) are one of the smallest owls in North America.  Although these small owls can dig their own burrows for shelter and nesting, they often use burrows that have been created by small mammals such as ground squirrels, prairie dogs, and desert tortoises and even adopt pipes or culverts.

These small owls are between 7.5 to 10 inches tall with a wingspan of 21 to 24 inches.  They weigh between 4.5 to 9 ounces.  Unlike most owls, burrowing owl males are slightly heavier than females and have a longer wingspan. 

Burrowing owls feed primarily on insects and small mammals but will also eat reptiles and amphibians.  They hunt while walking or running across the ground, by swooping down from a perch, or hover and catch insects in the air.  

Burrowing owls were once widely distributed across western North America.  Although burrowing owls are protected by the Migratory Bird Treaty Act, their numbers are declining.

 

Are burrowing owls using your construction site?

Observing burrowing owl behavior will help you determine if owls are using your construction site as habitat or if they are nesting in the area. Burrowing owls are often active during the day; however, you should check crevices, cracks, and burrows at your construction site for owls before beginning construction. Use of a fiber-optic scope or mini camera may help you look into a burrow to determine the presence of owls or nests.

If you discover an active nest, the site must be avoided until the chicks have fledged (able to fly). No construction should occur within a 250 foot radius around the nest. The nesting cycle takes a minimum of 74 days.

Nesting behavior

Burrowing owls breed from mid-March through August in southern Nevada. If owls are nesting, the site must be avoided until the chicks have fledged or it has been determined the nest has failed. The following are some behaviors that may help identify and determine if there is an active nest in the area:

A burrow that is occupied by burrowing owls will have debris such as twigs or feathers at the entrance.

Two owls at the entrance to a burrow is a good indication that the burrow is a nest site. One owl may disappear or reappear over a period of time. This is usually the female. She may have gone below to lay eggs or may be emerging to assist the male in hunting for food for the chicks.

An owl observed carrying food to a burrow is a very good sign there is an active nest. The owl is most likely the male providing food for the female while she is incubating eggs.

Chicks may appear at the burrow entrance when they are about ten days old.

Clark County projects

The following only applies to construction projects in Clark County.

Clark County holds a permit from the U. S. Fish & Wildlife Service authorizing “take” of desert tortoises during the course of otherwise legal activities on non-federal lands. Discouraging burrowing owls from breeding in construction sites on private land in Clark County is allowed. Desert tortoise burrows in Clark County can be collapsed from September through February if they do not contain protected wildlife. Contact the Nevada Department of Wildlife at 702-486-5127 if you find State protected wildlife such as Gila monsters.

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Protecting Burrowing Owls at Construction Sites Brochure

USFWS, City of Las Vegas and the Red Rock Audubon Society to enhance habitat for burrowing owls at Floyd Lamb Park (150MB Video) New Video

Last updated: April 16, 2014
February 11, 2014