The peak of the spring bird migration in Central Texas is April 22-May 12. About one third — 2 billion — of all spring migrating birds in the United States come through Texas. To help them safely journey north, the Lights Out, Texas campaign is encouraging Texans to turn off or dim lights from 11 p.m. to 6 a.m. each night during peak migration.
Artificial lights at night can disorient birds, even causing them to crash. In 2017, about 400 birds died after slamming into windows when they became disoriented by the floodlights of a 32-story building in Galveston.
Following the incident, Houston Audubon and American National Insurance Co., which owned the building, started Lights Out, Texas to encourage businesses, organizations, communities, government entities, and residents to reduce outdoor lighting during spring and fall bird migrations.
At the same time, Cornell Lab of Ornithology developed BirdCast, a migration forecast mapping system that used historical radar data to determine avian numbers moving across the country, even down to the county level.
Though Burnet County doesn’t have many high structures, artificial lighting around businesses and homes can negatively impact migrating birds, which expend energy flying and calling out due to confusion.
Birds, especially songbirds, tend to migrate at night. The moon and stars provide light for navigation, and it’s easier for birds to maintain a steady direction, speed, and altitude at night with decreased thermals from the daytime heat rising off of surfaces.
Turn off non-essential lights from 11 p.m.-6 a.m. during migration season, which in the spring is March 1-June 15.
Do not use landscape lighting on trees or gardens where birds might be sleeping.
For essential lights (security), use the following dark skies-friendly lighting practices: aim lights downward or use light shields; avoid shining lights into trees or the sky; use motion detectors or light sensors so lights are on only when necessary; and close window blinds at night.
The organization has additional guidelines for buildings taller than three stories:
Extinguish or dim exterior and decorative lighting (i.e. spotlights, logos, clock faces, greenhouses, antenna lighting), lobby/atrium lighting, and lighting in perimeter rooms on all levels of the building.
Avoid floodlights, illuminating interior plants or fountains and unoccupied floors, scheduling cleaning crews after dark, and blue-rich white-light emissions (lighting with a color temperature of over 3000 Kelvin).
Use desk lamps or task lighting rather than overhead lights, blinking lighting in place of continuously burning lights, and warm light sources (less than 3000 Kelvin) for outdoor lighting.