A butterfly rests on rapeseed, a relative of canola, in Frankfurt, Germany. Photo: Michael Probst / Associated Press
A 27-year study published Wednesday in the journal PLOS One found there's been a massive drop in insects in protected areas in Germany. The research shows even areas designed to preserve biodiversity are impacted by human actions.
Why it matters: Previous studies have estimated a roughly 50% drop in insects globally, writes Ben Guarino at the Washington Post. But this is one of the first studies to measure a decrease directly. Insects are important pollinators, but they're more than that. They eat waste, decompose detritus, spread nutrients and act as food for many species. "The whole fabric of our planet is built on plants and insects and the relationship between the two," Scott Black, executive director of the nonprofit Xerces Institute, tells the Post.
What they did: Researchers placed insect-catching traps in nature preserves in Germany. They made sure to move the traps around so they wouldn't harm insect populations.
What they found: The total weight of insects scientists caught each year dropped dramatically from 1989 to 2016. "The amount of decline, about 75%, is way too much to be attributed to just one or a few species such as bees or butterflies," study author Hans de Kroon tells Anna Azvolinsky at The Scientist.
Why it's happening: The study authors believe that climate change is not a factor. Instead, they implicate pesticide use and changes in how the land is used.