The Common Guillemot is a seabird that gathers on coastal cliffs to breed and otherwise lives at sea.
It is dark brown above and white below. Some birds have the bridled form, with a white eye-ring and a stripe behind the eye.
Twelve breeding Common Guillemots from Helgoland, Germany, carried GPS tags for 8–26 days in 2016 and 2017. Researchers tracked them around three offshore wind farms 23–35 km north of the island and recorded whether turbine blades were rotating. The farms covered 105 km² and contained 208 turbines.
The birds’ selection of wind-farm areas was estimated to be 63% lower than their selection of surrounding waters. Avoidance rose to an estimated 75% when turbine blades were rotating. One bird in each study year briefly entered the farms on two or three occasions. Guillemots mainly approached from the eastern edge while resting or diving, and rarely approached the farms while commuting.
An extinction-risk assessment has not been added yet.
Offshore wind planning can include surveys of the waters breeding seabirds use for feeding and resting, together with turbine-operation data. Records of where guillemots forage and where they avoid can inform decisions that reduce effects on marine habitat.