Dave Goulson
Silent Earth by Dave Goulson

Dave Goulson’s Silent Earth: Averting the Insect Apocalypse is something of a roller-coaster ride in that the first 250 pages of the book detail the evidence for insect and biodiversity collapse that is happening right now all around us, before lifting our spirits in the final 50 pages with details of what we can all do about it. This is urgent stuff because the evidence is clear that we really are living on the brink of an ‘apocalypse’. It also book-ends Rachel Carson’s 1962 book Silent Spring about the havoc wreaked on our environment by pesticides. Who would have thought that we’d need another siren to be sounded on the same topic? This book, unfortunately, is it.

The book’s generally informal style does not, however, conceal the hard science that underwrites it. The author is Professor of Biology at University of Sussex, and his speciality is bee ecology. He has published north of 300 scientific articles on the ecology and conservation of bumblebees and other insects. It was his research that linked the use of neonicotinoid insecticides on crops with an 85% reduction in the production of new queen bees. This led directly to the 2013 EU Moratorium of the use of such pesticides on various flowering crops. At the time, the UK government was opposed to the ban. Last year the EU expanded the ban to all field crops. With this sort of track record, Professor Goulson can afford to come over as being impassioned. And the book reads all the better for it. It is detailed and engaging, but all the time it is framed with the authoritative scaffolding of hard science. With the IPCC’s latest report this August being a ‘code red for humanity’, and with Cop26 coming to Glasgow in November, this is all timely.

Every third bite we take is of food that requires pollination by pollinators. (The other two bites will be of meat or of wind-pollinated crops such as grasses, nuts and cereals, anemophily being the name of that process.) If pollinators were no longer here to be our key workers, imagine the trouble we’d be in. It’s helpful too that Goulson points out that it is not just bees and bumblebees that are our pollinators. Butterflies, moths, wasps, beetles, ants, flies and hoverflies also provide this labour in our gardens and fields. This explains why we should be profoundly concerned about all insects, some of which, invisible from view, also enrich our soils and process rotting matter.

The author details the causes of insect decline in starkly authoritative terms. There are many, all caused by us: habitat loss, pesticides, herbicides, artificial fertilisers, parasites and diseases, climate change, light pollution, and accidental species introductions. Separating one from the other requires careful research, but the cumulative effect of these onslaughts is now well known.

The Krefeld Society has been trapping flying insects across Germany since the 1980s, building up a statistical picture of insect populations. They had amassed insects from nearly 17,000 days of trapping across 63 sites over a period of 27 years. The author was asked to make sense of what they thought their data was showing. It turned out that between 1989 and 2016, the overall biomass weight of insects caught in these traps had fallen by 75 percent. In midsummer, when European insect activity should be at its peak, the decline was a staggering 82 percent. Subsequent studies by different groups of entomologists have reinforced these findings, sometimes recording even more catastrophic declines, particularly for butterflies in the USA and southern California. In the largest and longest-running national insect recording scheme in the world - here in the UK - declines of butterfly counts have been measured at 46 per cent and, for what might be thought of as habitat ‘fussy’ butterflies such as fritillaries and hairstreaks, a fall of 77 percent has been measured. Moth, aphid and fly numbers appear to be in decline too. And so on for ground beetles, caddisflies, spittlebugs, and river insects. Thirteen of the UK’s twenty-three bumblebees seem to have suffered shrinkage in their range between pre-1960 and 2012; two species have gone extinct. Since 1850, twenty-three bee and flower-visiting wasp species have gone extinct. Research substantiates the insect loss noted by Michael McCarthy in his 2015 book Moth Snowstorm: Nature and Joy, also reviewed on this site.

Should we be surprised that similar losses are being seen amongst those that are further up the food chain, our birds? From spotted flycatchers to grey partridges, from nightingales to cuckoos: all have suffered drastic population declines as their insect diet has shrunk. Though the detail varies from place to place, the broad picture remains the same. The collapse begins at the bottom of the food chain. Lose the insects and sooner or later the pyramid which rests on them will no longer be supported.

In his celebrated 1992 book The Diversity of Life, the great American biologist E.O. Wilson wrote the following about insects and arthropods (insects, arachnids, myriapods and crustaceans):

So important are insects and other land-dwelling arthropods that if all were to disappear, humanity probably could not last more than a few months. Most of the amphibians, reptiles, birds, and mammals would crash to extinction about the same time. Next would go the bulk of the flowering plants and with them the physical structure of most forests and other terrestrial habitats of the world. The land surface would literally rot. As dead vegetation piled up and dried out, closing the channels of the nutrient cycles, other complex forms of vegetation would die off, and with them all but a few remnants of the land vertebrates. (E.O. Wilson, The Diversity of Life, p. 125)

So much for the so-called ecosystem services that our fellow travellers provide for free.

Goulson’s final 50 pages offer a wealth of options for different ‘stakeholders’: for all of us, for gardeners and allotment holders, for national governments, for local governments, and for farmers. We could all be busy following his advice. We’ve already picked three for the small town centre garden that we’re lucky enough to be custodians of: to use no chemicals, to mow less (in fact devoting 50% of ‘the lawn’ to wild flowers), and to ensure that the rest of the space is replete with pollinator-friendly plants. There are a further half-dozen or more recommendations that we are already following. We’re not holier than thou, and no doubt could do a lot better.

I’m also lucky to be able to participate in a local ‘citizen science’ project to keep a closed cemetery (one that’s ‘full up’ and no longer open to the public) free of chemicals and full of pollinator-friendly plants (instead of severely-clipped neatness). The 0.4 hectare, town-centre Heene Cemetery undergoes constant species surveillance and I am privileged to be able to contribute photographs to a website that details the gradually increasing species count (some 380 at the time of writing), many of which are pollinators. We have some way to go yet to even touch the staggering record that Dave Goulson cited in a recent Guardian article of wildlife gardener Jenny Owen who spent 35 years cataloguing everything in her eighth-of-an-acre Leicester garden. She notched up a remarkable 2,673 different species, of which some 1,997 were different insects. A Wikipedia article on her says that she counted 91 of the UK’s 256 species of British hover flies in 14 years. In our local cemetery, we have counted just 6. The bar has been set very high!

Alongside this one can simply marvel at the insects that live beside us. Whether they are pollinators or not, they are often beautiful, occasionally weird, and usually astoundingly interesting. My cemetery time allows me to get a macro lens close to them and the results are delightful. Here’s a small sample. Click or tap each for larger versions.

1/6 Peacock butterfly on buddleia
Peacock butterfly Inachis io on buddleia, © Rob Tomlinson
2/6 Hoverfly Syrphus Ribesii
Hoverfly Syrphus ribesii, © Rob Tomlinson
3/6 White-tailed Bumblebee fending off attack
White-tailed Bumblebee Bombus lucorum fending off attack, © Rob Tomlinson
4/6 Long Hoverfly
Long Hoverfly Sphaerophoria scripta, © Rob Tomlinson
5/6 Meadow Grasshopper
Meadow Grasshopper Chorthippus parallelus (not a pollinator but interesting for what it is), © Rob Tomlinson
6/6 Common Green Shieldbug (not a pollinator but interesting for what it is)
Common Green Shieldbug Palomena prasina (not a pollinator but interesting for what it is), © Rob Tomlinson

At the time of writing, Dave Goulson has a petition to “Ban urban and garden pesticides to protect bees, other wildlife and human health” at https://petition.parliament.uk/petitions/590309. It needs more than 100,000 signatures before January 26th 2022 for it to be considered for ‘debate’ in Parliament. If you live in the UK, please consider signing it.

One of the most powerful chapters that Professor Goulson has written concerns what he calls shifting baseline syndrome, the fact that “we accept the world we grow up in as normal, although it might be quite different from the world our parents grew up in”. As he says, “we humans are also poor at detecting gradual change that takes place within our lifetime”. His work in scientifically measuring change over time has done much to demonstrate the veracity of this. The book’s penultimate-but-one chapter, A View from the Future, merits you getting a copy for yourself, as it imagines one of his grandchildren in 2082 looking back at humanity’s failures to get to grips with these problems. On guard duty over-looking a garden containing valuable vegetables, the perspective serves as a terrifying bridge between the sciences and our daily lives. Dystopian it may be, but it is a strong antidote to shifting baseline syndrome and sets the reader up for the 50 pages of recommendations that bring the book to a close.

Imminent apocalypse may appear to be energy-sappingly pervasive, and the concerted heavy-lift policies that governments can lead the way with are largely absent. Yet there are countless little things that we can all do that really will make a difference. Insects reproduce quickly and our efforts can make a difference in helping them rebuild their numbers. On this Professor Goulson is clear: we can all make a difference by acting in favour of our pollinators and the myriad other six-legged beings on whom we really do depend. This very special book is capable of galvanising us into action.


[Silent Earth by Dave Goulson is available in the UK from Hive.co.uk.]