Ohio Wildlife Center’s Lights Out Columbus project concluded its fall monitoring in November with new data collected about migration threats in the heart of the city. A rescued White-throated Sparrow was also successfully fitted with a nanotag and released in October, enabling key information about the bird’s migration pattern to be tracked during its travels to southern wintering grounds.
The sparrow is the first bird during the spring and fall monitoring seasons to be tagged with a tiny radio transmitter (nanotag) that sends a unique signal to Motus station receiver towers crossing from Canada to South America. The Columbus Zoo and Aquarium has two Motus stations – one at the zoo and one at the Wilds near Cumberland, Ohio.
The Zoo’s Conservation Fund provided the grant funding for Lights Out Columbus and the purchase of the nanotags. According to Stormy Gibson, education director at the Center and Lights Out Columbus project director, specific criteria are used to determine which bird species are tagged. The Center is working with the zoo and researchers at the Carnegie Museum of Natural History to develop the most effective nanotag processes.
“The information picked up by the Motus towers from the tagged birds is critical for researchers building the data sets about how the rescued birds do after building or window collisions when they are treated and released back to their migration paths,” Gibson said.
Nearly half of known bird species are migratory, moving from one habitat to another in changing seasons. Collisions with buildings from disorienting lights and large expanses of reflective glass are a leading cause of bird fatality and up to half a billion birds are estimated to die each year in North America from building collisions, particularly during migrations, Gibson noted. The north and east facing sides of buildings in Columbus correlated with the highest number of bird strikes during fall migration.
Fall data collected from volunteers who canvassed specific streets and buildings each day from 6 a.m. to 8 a.m. indicated 21 buildings on the route had strikes from birds, with 38 strikes tracked to one building. Buildings with the highest percentage of glass also registered the highest (62.5%) percentage of hits. Birds are injured by striking either the windows or sides of the buildings during their flight over the city, or by exhaustion as they circle buildings in confusion from bright lights and reflected surfaces.
Injured birds are collected by volunteers and transported to the Wildlife Hospital for an exam, care, nutrition, and rest. Most are re-released within a day to continue their migration.
Highlights and data from the fall monitoring include:
- 45 volunteers and 19 OWC staff participated in the monitoring
- From August to November, 711 hours were logged over 72 days of monitoring downtown
- Volunteers walked 912 miles
- 36 species of birds and 7 bats were collected
The highest number of species collected were Ovenbirds (24), White-throated Sparrows (14), Tennessee Warblers (9), Blackburnian Warblers (6), Brown Creepers (6), and Yellow-bellied Sapsuckers (5).
Gibson noted that an important facet of Lights Out Columbus is the partnerships with downtown building owners to modify lighting during the migration months. There are about 29 building sites that reduced external and internal lighting at night to help cut down on bird strikes.
“This is a project that has worked to create collective efforts with volunteers and businesses to save Neotropical songbirds,” Gibson said. “We want to reduce bird injuries and deaths, as there are so many factors that threaten successful migrations through urban areas,” she said.
Gibson pointed to a report issued in October by Audubon Great Lakes that indicated 389 bird species are threatened with extinction from combined factors of climate-related impacts such as sea level rise, Great Lakes level changes, urbanization, drought, heat, fire and rain as additional reasons to sustain projects like Lights Out Columbus.