Insect populations have been devastated but how can we help them?
Insects are rapidly declining across the world: some studies are showing collapses of up to 75% on previous records but there’s lots we can do to reverse it. All this and much more are all explained in great detail by Dave Goulson, Professor at the University of Sussex whose book, “Silent Earth: Averting the Insect Apocalypse” was recently published. His book comes almost 50 years after Rachel Carson warned about the widespread use of pesticides in Silent Spring.
Firstly Goulson points to research which blames the catastrophic decline in insect numbers on farming methods, pesticides, climate change and indeed by the breaking up of rich habitats. He gives two explanations for why the collapse in insect numbers is barely noticed among the general population. 1) Shifting baseline syndrome where we get used to what we see (and experience) around us in the moment and slowly forget how things were different in the past. And 2) Gaslighting: Goulson also believes that where we do sense change we can often downplay it’s importance. However the collapse in insect numbers is certainly something to be concerned about. Indeed some scientists fear that this loss of biodiversity will have a more immediate effect on many of us than climate change.
But why are insects important? In basic terms insects are the foundation for that the world of nature is built upon: insects pollinate and eat plants and in turn they are eaten by predators further up the food chain. A whopping 87% of plant species (and 75% of all agricultural food crops) depend on insects for pollination. And it’s not just bumblebees and honeybees who do the work: a whole range of species including ants, flies and moths all play their role in adding to natures bounty. So in basic terms without insects we would be forced to hand pollinate certain crops such as is the case in orchards in China. Without insects we would, in practical reality, be confined to eating wind only pollinated cereal grains which would be devastating for global diets.
Next consider your compost pile: nothing gets processed here without an army of bugs processing and filtering through leaves, sticks and all manner of rotting matter. Indeed under the earth, worms are busy adding life and energy to our soils. And then of course are the biological control provided by insects in a healthy eco-system. Certain insects populations have slowly evolved to resist pesticide use creating a never ending cycle of chemical application: balanced ecosystems that encourage a wide range of predatory insects help ensure no one pest can get out of balance. The vast almond orchards of California have been enriched with pollinator friendly wildflower planting in an effort to get insect populations back into sync. And initial results have been very positive: insect numbers have bounced back quickly.
And this is the most encouraging point: Goulson reminds us that because insects can reproduce very quickly their decline can be arrested very quickly. Even the smallest garden owner can get involved: grow native plants as these will help our locally adapted insects best. Avoid large areas of manicured lawns as these areas are of much less benefit than areas left wild and areas brimming with flowering plants. Avoiding pesticides (and herbicides) is also essential. Building insect hotels is another action and one that the kids can get involved in. Mowing lawns less often during the growing season is also simple yet surprisingly beneficial.
Another suggestion which surprised me was that beeping as a hobby is not recommended because of the risk of disease passing from farmed honey bees into the native wild species. Indeed it is now being said that choosing to keep bees to save insects is like keeping chickens to save wild birds.
A further recommendation is to reduce the use of outdoor lighting: nocturnal light pollution has risen considerably and they often confuse and exhaust insect populations. In Europe populations of nocturnal moths is falling much more rapidly than day time moths and the difference is being attributed to light pollution. This helps explains why ecologists are so loathe to recommend lighting on canals and in species rich habitats. Where lights are necessary they can be placed on sensors or timers.
Finally it is often said that you don’t miss something until it’s gone and in the case of insects that may be particularly apt: scientists have documented over one million different species of insects but they estimate that there may be another 9 million undiscovered species on earth, waiting to amaze.