# US wind farms killed about 18.7 million bats of 28 species in 1981–2024, PNAS study finds

- Published: 2026-11-06 18:46 UTC
- Section: Planet › Ecology & recycling
- Tags: bat mortality wind farms, wind turbines United States, 18.7 million bats, turbine shutdowns, wind farm siting, bat conservation, wind energy and wildlife
- URL: https://realtech.media/news/rt-96cc86cb0a5e415fffd63df5_us_wind_farms/

**A PNAS study estimates 18.7 million bat deaths at US wind farms over 1981–2024; annual losses reached 1.5 million by 2021, and the true toll may be higher.**

![US wind farms killed about 18.7 million bats of 28 species in 1981–2024, PNAS study finds](https://sgzwpqqelzmajkcubgkl.supabase.co/storage/v1/object/public/rt-media/2026/11/d88b30ae582b6452.webp)
*ua.news*

Between 1981 and 2024, approximately 18.7 million bats of 28 species were killed at wind farms in the United States. This follows from a study published in the journal Proceedings of the National Academy of Sciences, as reported by ua.news [1]. By 2021, the annual figure had risen to 1.5 million bats per year [1]. The study thus covers both the cumulative losses over the period and the growth of annual mortality.

## Why the toll may be higher

The scientists explain that the actual scale of bat mortality may have been underestimated [1]. Bat carcasses are often eaten by scavengers or get lost in tall grass, so they are not included in the statistics [1].

## Measures to reduce bat deaths

According to the study, mortality can be reduced by carefully selecting sites for wind farm construction and by temporarily shutting down turbines during periods of bat activity [1]. A European study of 141 wind farms showed that such measures can reduce animal deaths by more than 80% [1]. These two measures, site selection and temporary shutdowns, are the ones named by the scientists.

## Sources

1. [ua.news](https://ua.news/en/world/vitrovi-elektrostantsiyi-u-ssha-sprichinili-zagibel-maizhe-19-milioniv-kazhaniv-za-40-rokiv)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-96cc86cb0a5e415fffd63df5_us_wind_farms/