Insect populations are in severe decline globally. The acuteness of this deterioration is hard to pinpoint because of insufficient research and monitoring of insect populations. Most of the studies that exist have been done in Europe or the U.S. Although some invertebrate populations have increased, the majority have fallen. The general view of scientists is that we are losing 1-2 percent of insect populations annually and that around 40 percent of species are threatened with extinction.
The drop in abundance, biomass, and diversity of insects has been almost totally driven by human activity. Habitat loss from urbanization and agricultural intensification, widespread pesticide use, light pollution, and climate change account for most of this decline. These in turn are creating serious threats to ecosystems, ecosystem services, food webs, and bird populations.
People around the world are mobilizing to counter this threat. The Pollinator Pathway Project is helping create a network of independent organizations to build links between existing green spaces. They are establishing connected, pesticide-free zones where insects and pollinators can find food and shelter. Nectar-rich, native plants now fill alleys with color and fragrance when they were previously marked by neglect and litter. Cheerful murals are sometimes part of the mix. Local volunteers care for the spaces, water the plants, and enjoy the renewed abundance of bumblebees, butterflies, hoverflies, and ladybugs. Birds also love these corridors since they flourish where insects are abundant. Insects are a big part of their diet.
Similar to the habitat isolation many mammals are experiencing caused by crisscrossing highways, insects are being isolated in smaller and smaller wildflower-rich grasslands. Habitat fragmentation is a big issue. Not only are alleys getting converted into insect-friendly corridors, but so are farm hedgerows, meridian road dividers, parks, home gardens, and road verges. Some of these transformations take only a week of volunteer work, while others take longer and involve public-private collaboration. More than 300 towns in 24 U.S. states have joined the movement.
Founded in 2011, the U.K. conservation charity Buglife has created a three-kilometer-wide “insect superhighway map” connecting wildflower-rich habitats the length and breadth of Britain. In addition, it has incentivized local groups to fill in the highway gaps. To date, more than 3,800 groups and projects have been added to connect and enhance biodiversity. Linking habitat can include bare ground for ground-nesting bees and leaf litter for overwintering insect nests. Some may perceive less-manicured landscapes as messy or unkempt, but they provide great benefits.
Once again, we are realizing that things that are good for nature are also good for people.
