What do we lose when species die? –Insights magazine
The Insect Crisis, Oliver Milman, Atlantic Books
Wild and Broken Sounds, David George Haskell, Black Inc.
In the 1990s, we used to drive in the countryside, from the city and beyond the Great Dividing Range to flat farmland, and the front of the car was covered in beetles. It’s rare now to be bothered by bugs on the windshield, or to see the swarms of summer bugs we used to see.
In Oliver Milman’s alarming and captivating book, he tells us that there has been a 75% decline in the world’s insects in “protected areas”, both in terms of populations and species, in during the period 1989-2017. A Danish researcher had a more scientific version of the windshield experiment, in the same piece of Danish countryside for 20 years and found an 80% drop. In a rainforest in Puerto Rico, the figure was around 80-90%.
Three quarters of animal species on Earth are insects. Their biomass is twenty times the combined mass of all other animals. Unlike dinosaurs, they survived previous mass extinctions quite well. A human-induced crisis, as Milman calls it, is the first time they’ve been really hit hard. And it’s not just bad for insects. They are indicators of the ecological health of the planet.
Most of us don’t understand all that insects do for us, in their specialization and interconnection with the rest of nature. As David George Haskell, another insect apologist, writes, in addition to simply being an example of the richness of the natural world, they have niche relationships with flowering plants and are vital for pollination, such as the indicates the recent bee panic. Milman comments that while the loss of polar bears would undoubtedly be tragic, it would not have much impact on human affairs, while the mass loss of insects would be a disaster for agriculture (the dreams of robot bees doing the work are simply unrealistic.)
For those who fear crawling critters, or for those who live in tropical regions, fewer flies and mosquitoes might seem like a positive outcome, as they transmit disease to humans, but flies, for example, pollinate cocoa trees, they are therefore vital for production. of chocolate. Flies also do housework. And, ironically, insects such as flies and mosquitoes are likely to benefit, not suffer, from increased urbanization and global warming.
For other insects, climate change is happening too quickly for adjustment. Another cause of loss is increasingly monocultural agriculture. Ironically, while we need pollinating insects for agriculture, monoculture and landscape maintenance are bad for them, and the birds that feed on them. Loss of wild roadsides, hedgerows, wildflower meadows and strips of bush contribute to this. Ironically, again, some cities are more habitable for insects and birds due to the variety of plants found in parks and gardens. Insect loss is also attributed to agrochemicals. In France, a third of birds have disappeared, their food sources being affected by the application of pesticides and herbicides, which agrochemical companies are still desperately campaigning for.
Birds and insects feature prominently in Haskell’s fascinating book on biodiversity and the sounds of nature. He has already written in detail about the surprising interdependence of forests. Here he turns his attention to the sounds of the word animal that are under threat, and generally unloads a torrent of amazing information.
His book is a cavalcade of descriptions of auditory sensations, including the world beyond human ears. The human ear is incredibly complex and filters out volume and frequencies, so we don’t get bombarded. Animals occupy niches in sound frequency and time of day, to avoid competition for the same wavelength and to be heard among the din of a forest. California sparrows have regional dialects in their songs, much like whales. The resulting sonic fecundity rivals the visual variety of the animals. Rather than an arms race, it is a race for the arts.
Birds compensate for noise in cities by increasing their volume. But some animals cannot compensate. The number of whales is decreasing in some places due to shipping noise. Whales need sound to hunt and communicate. Sounds travel farther in the water and whales use a “lens” of water – a layer in the ocean – to send calls thousands of miles away, but in this soundscape large ships add pollution deafening and confusing sound. Worse still are seismic surveys – sonic blasts aimed at the ocean floor to map oil deposits. For whales, it’s like having a jackhammer in your living room for humans. Loud soundscapes are also a problem for marine life in recreational fishing and small outboard motors.
It is possible to design less noisy ships and slow down sea speeds. And we can stop oil drilling in the oceans, which is bad for other reasons. For our six-legged friends, more messy gardens, more variety, more flowers, buying organic products, less light in cities, less pesticides, all of this is useful. Just like being aware of their vital importance for biodiversity and our own survival.