Burrowing Owl Winter Ecology and Use of Artificial Burrows in South Texas
Project Fact Sheet
Burrowing Owls
Winter in South Texas 
Project Description
Burrowing owls (Athene cunicularia) are unique migratory birds. In the western United States and southern Canada, they breed in dry grasslands, using animal burrows, such as those of prairie dogs, for nest sites. In the winter, burrowing owls migrate to California, Arizona, New Mexico, Texas, and parts of Mexico. Although they do not nest during the winter, they still require burrows for protection.
Burrowing owls are small, long-legged birds of open country from Canada to Mexico, but are declining at an alarming rate. The burrowing owl is one of only 11 species of birds identified for joint protection by an international environmental agreement between the United States, Canada, and Mexico. It is listed as endangered in Canada and threatened in Mexico. In the United States, the U.S. Fish and Wildlife Service currently classifies the burrowing owl as a Species of Management Concern and has initiated a formal review of its population status.
South Texas is a major wintering area for the burrowing owl, based on recent bird surveys conducted by the Texas Gulf Coast Field Research Station (TGCFRS), Texas A&M University-Corpus Christi (TAMU-CC), and the Canadian Wildlife Service (CWS). The importance of south Texas to burrowing owls was not formerly known because the owls disperse widely over this large region of Texas, and they inhabit highly altered or disturbed habitats normally not considered good wildlife habitat.
South Texas historically featured coastal prairie and native brush, but with the conversion of much of this region to agriculture, native grasslands containing animal burrows have also been lost. As a result, burrowing owls wintering in south Texas use road culverts (usually along roads adjacent to cultivated fields) instead of natural burrows. Vehicles pose a serious threat for burrowing owls roosting along roads.
The use of culverts, instead of natural burrows, appears to be an adaptation to a drastically changed landscape and has presented wildlife managers in south Texas with an unusual challenge. The TGCFRS has joined TAMU-CC and the CWS to study the winter ecology of this species, in hopes of finding answers to why burrowing owl numbers are declining. Reversing the decline in burrowing owl populations is a long-term goal for this research team.
Long-term objectives for burrowing owl research and conservation in south Texas are:
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Developing a questionnaire to identify landowners who may have burrowing owls on their land, then using those responses to help estimate burrowing owl winter population size in south Texas.
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Developing educational materials and partnering with local news media to improve public awareness of this species.
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Constructing artificial burrows made from industrial drain pipe, placed away from roads, then monitored over several winters.
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Identifying individual burrowing owls in south Texas and tracking their movements during the winter period by fitting the owls with leg bands and radio transmitters.
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Determining daily activities and behavior of burrowing owls using video surveillance at selected burrow sites.
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Calculating winter survival rates and determining causes of mortality.
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Determining burrowing owl winter diet by identifying prey remains in regurgitated pellets.
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Mapping owl locations and territories using Geographic Information System (GIS) software.
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Assessing any contaminants that may occur in the owl diet by sampling insects and small rodents near known roost sites, then analyzing these prey items for contaminants.
Project Partners
"Winter VIP" by Jim Rostohar, Naval Air Station - Kingsville
Project Gallery
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Burrowing owl peeking out of burrow. (Photo by Jerry Batey, TAMU-CC)
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Burrowing owl on ground.
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Road culvert used as winter home for burrowing owl in south Texas.
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Burrowing owl from Port Aransas using a storm drain for a burrow.
Project in the 
- Navy Provides Winter Quarters for Injured Owl ---(Currents: Pollution Prevention and Compliance (by Jim Rostohar) in the Navy's Environmental Magazine, Winter 2003)
- November 29, 2002 Corpus Christi Caller-Times Thorns and Roses: 11.29.02
- November 23, 2002 Billings Gazette Burrowing Owl Gets New Texas Home
- November 23, 2002 Corpus Christi Caller-Times Return to Freedom
- November 21, 2002 Corpus Christi Caller-Times Montana Owl Gets Snug Hole in Texas
- October 2002 Birding (Vol. 34, No. 5, pp. 451-458) Defending the Steppingstones of Migration by Chris Eberly
- October 2002 TRIO "On the Trail of the Disappearing Owl"
- July 14, 2001 Corpus Christi Caller-Times "A New Home for the Winter" (front page in .pdf)
- April 8, 2001 Victoria Advocate, "Fertilizer Should Be Applied Now"
- December 1, 2000 Corpus Christi Caller-Times, "Owl Spotters' Help Sought for a Study"
- February 22, 2000 Corpus Christi Caller-Times, "Caught Between a Clod and a Hard Place to Find, An Owl Lays Low"
- February 18, 2000 Corpus Christi Caller-Times, "New Projects Help Endangered Owls"
Owl Links
- Burrowing Owls (Canadian Endangered Species--Canadian Wildlife Service Species at Risk)
- Burrowing Owls in South Texas
- The Decline of the Burrowing Owl--Encompass Magazine, October, 1997 (Geoff Holroyd, Canadian Wildlife Service)
- Burrowing Owl Identification Tips (USGS Patuxent Wildlife Research Center)
- Effects of Management Practices on Grassland Birds: Burrowing Owl (Report) (USGS Northern Prairie Wildlife Research Center)
- Burrowing Owl Migration Tracking for HAM Operators