Wind turbines on the sea have a negative impact on the population of loons, according to a study. These include the fish-eating waterfowl, red-throated diver and black-throated diver. Loons almost completely avoid offshore wind farms and directly adjacent areas, according to a study published in the journal “Scientific Reports” by a team led by biologist Stefan Garthe from the West Coast Research and Technology Center at the University of Kiel.
Garthe and colleagues have studied how loons have changed as a result of the construction of 12 offshore wind farms in the south-eastern North Sea. The team analyzed data collected from ships and aircraft between March and April 2010 and 2017. From this it modeled how the density of loons changed in the areas up to a distance of ten kilometers from the respective wind farm and beyond.
Result: The distribution and frequency of loons changed significantly after the construction of the wind farms. The birds therefore almost completely disappeared from the immediate vicinity of the wind turbines. “The population of loons decreased by 94 percent within one kilometer of the wind turbines and by 54 percent within ten kilometers of the wind turbines,” the researchers said.
From Borkum to Helgoland
According to the study, loons have almost completely disappeared from the area around the wind farm regions of Bard/Austerngrund and north of Borkum. “Instead, the birds gathered in high density in an area north-west of the wind farm near Helgoland.” If bird densities increase in other areas, it may lead to increased competition there. According to researchers, the estimated population of loons in the southern North Sea fell by 29 percent from almost 35,000 individuals before the construction of the wind turbines to less than 25,000 birds after construction.
According to the researchers, no other seabirds showed such a significant negative response to the presence of the wind turbines. They suspect that the construction of the facilities will affect the loons’ foraging activities, since their range of action is now restricted to smaller areas.
“We have no doubt that renewable energy should meet a large part of our future energy needs,” the team writes in the study. But politicians should also take into account the existing biodiversity crisis. Analysis of many species in different locations should help identify which marine waters are best suited for wind turbines without jeopardizing conservation goals.
The authors refer to previous studies that have already shown that different seabird species respond differently to offshore wind farms: some species avoid wind farms, leading to a consequent reduction in their habitat. However, some species would be literally attracted, which in turn increases the risk of collisions with wind turbines.
