Painting one wind turbine blade black cut bird deaths by 70%, and now Wyoming is testing it

A solution is underway for bird strikes caused by wind farms. Painting one wind turbine blade black may help protect birds from being struck by the blades, while still producing clean energy for a better future. A study linked the change to a drop of more than 70% in bird deaths, and a larger Wyoming trial is now testing whether that result holds up.

What happened?

BGR reports that interest is growing in a straightforward idea to reduce bird strikes at wind farms: painting one of a turbine's three blades black. The goal is to make the spinning turbine more visible to birds.

The main evidence so far comes from a 2020 paper in Ecology and Evolution, which reported that annual bird fatalities dropped by more than 70% after a blade was painted. But that result came from a very small experiment, with just four painted turbines and four unpainted control turbines.

PacifiCorp is now trying the approach on a much larger scale at its Glenrock wind farm in Wyoming, BGR noted. The project involves painting individual blades on 36 turbines, with support from government agencies, nonprofits, and Oregon State University researchers who want to see whether the earlier result can be repeated more broadly.

Why does it matter?

Wind is already a significant source of electricity in the United States, accounting for a large chunk of nationwide electricity. In fact, it generated 10.2% of U.S. power in 2023, more than any other renewable energy source. As wind energy continues to expand, reducing its impacts on wildlife has become an important area of research.

The issue of bird collisions matters for animal safety and also, in part, because some of the birds killed by turbines, including golden eagles and many migratory species, are protected by federal law. And while some claims about wind turbines and bird deaths can be overstated, the underlying issue is a real concern. If a low-cost visual change can reduce those deaths, it could help future wind development proceed more responsibly.

Actually applying the paint can be difficult, though. One of the researchers involved in the Norwegian study told Audubon that the work was done by "a specialized team of painters who could rappel onto the turbine blades and paint them in midair." That likely helps explain why the original trial was so limited.

Even so, if the larger test shows the same benefit, adding black blades to new turbines would be much simpler than reworking wind-energy systems from the ground up. For now, the Wyoming project is expected to provide some strong evidence on whether the strategy works under real-world conditions.

The mood among researchers seems to be a mix of optimism and restraint. The Norwegian study produced striking numbers, but PacifiCorp and its partners are using this larger trial to see whether the effect can be reproduced and whether any unintended harms emerge.

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