Insects play a crucial role in sustaining life on Earth. They pollinate plants, recycle nutrients, and form the foundation of food webs in both terrestrial and freshwater ecosystems. Without insects, the rich biodiversity that supports our planet would not exist.
However, global studies show a widespread decline in both insect abundance and diversity. According to a new study by researchers from the University of North Carolina at Chapel Hill, insect populations are also shrinking in relatively undisturbed landscapes.
The research team quantified the abundance of flying insects during 15 seasons between 2004 and 2024 in a subalpine meadow in Colorado, an area with decades of weather data and very little direct human activity. The results revealed an average annual decline of 6.6% in insect abundance, amounting to a 72% drop over the 20-year period. The study also linked these losses to rising summer temperatures.
Most previous studies of insect loss have focused on areas heavily influenced by agriculture or urbanization. This new research fills an important gap by showing that steep declines can occur even in pristine areas where human disturbance is minimal, suggesting that the changing climate may be a key driver.
Mountain regions, which are home to many unique and locally-adapted species, are especially vulnerable. If these declines continue, the rich biodiversity found in high-altitude habitats could be in jeopardy.
The findings highlight the urgent need for broader and longer-term monitoring of insect populations and reinforce the importance of addressing climate change. Even remote regions are not out of its reach.
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Web Links
Long-term decline in montane insects under warming summers
Insects are disappearing from the last places we thought were safe
Photo, posted July 16, 2019, courtesy of Tom Koerner / USFWS via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio