James Watterson reviews “Silent Earth – Averting the Insect Apocalypse” by Dave Goulson.

This is an excellent book, clearly written, informative and persuasive. The title echoes Rachel Carson’s “Silent Spring,” and Goulson’s work suggests that although much has changed in the sixty years that have passed since the publication of that seminal text we have neither fully come to terms with its lessons nor adequately reckoned with new risk factors that now threaten an insect apocalypse.

In common parlance an apocalypse is often understood to be a great disaster, perhaps of world ending proportions. That is the sense in which Goulson is using it here, but its original meaning in Greek is, “to reveal, to draw back the curtain,” and I certainly found this work to be revelatory.

After a brief introduction in which the author traces his own fascination with insects back to his childhood over fifty years ago, the remainder of the book is split into five parts and twenty one chapters. Between chapters we are treated to a series of short pen sketches of a range of fascinating insects from Femme Fatale Fireflies to Hyperparasitic wasps.

The first section looks at “why insects matter.” Goulson notes that they provide a range of eco-system services from pollination and pest control to the decomposition of dung and carrion. He argues, following E. O Wilson, that the attempt to put a dollar value on such services is ultimately meaningless as “without them the environment would collapse into chaos and billions would starve.”  However, important as insects are from a practical and economic standpoint, Goulson wants us to move beyond this anthropocentric model to consider their intrinsic worth. He touches on the breath taking variety of insect life, its beauty and wonder and, although not a believer himself, he challenges those who do have faith to consider if we really believe that God created all of this amazing life just so that we could recklessly destroy it. 

In the second part of the book the author looks at the evidence for insect declines. Here, he acknowledges that although there is an abundance of evidence for vertebrate decline in the modern era, invertebrates are much less well studied. He notes dramatic declines of over 75% in the trapped biomass of insects in the Krefeld study in Germany in 26yrs to 2016 and over 35yrs to 2013 in a study in Puerto Rico. However, he is careful not to overstate his case noting the small number of long term data sets, the fact that many of the most common insect species are not monitored at all, and the wide geographical gaps in the data. Nevertheless, he is able show that the evidence that we do have is significant and points strongly towards a precipitous decline in many species and in over all insect populations across several continents and a variety of habitats. In the UK he notes serious declines in our butterfly, wild bee and hover fly populations, and the lack of long term data on other insects.

In the third and much the longest part of the book Goulson turn his attention to the possible causes of this decline. He considers the impact of pesticides and notes the quite sickening tactics of the industry in seeking to mislead, obfuscate and delay regulation. He comments on the direct and indirect impacts of herbicides (toxicity to insects and removal of food species), light pollution, industrial agricultural practices, the spread of invasive species and insect parasites and diseases by humans, habitat loss and fragmentation and of course climate change. He notes that although these threats are almost invariably studied in isolation they act in concert, with insects weakened by one hazard more likely to succumb to another. He also points out that although species might be expected to adapt to climate change by shifting their ranges to more suitable climes, in many cases habitat loss and fragmentation will mean that they are left with nowhere to go, or no way to get to a suitable environment.  

Following this sobering review of the causes of insect decline, in the short fourth section the author invites us to imagine a world where these trends have continued unchecked. He shows us a vision of England around 2080. The climate is now Mediterranean, biodiversity has collapsed spectacularly, many plants need to be pollinated by hand, food production has fallen precipitously, fast breeding pest species have proliferated and their traditional predators have failed to keep pace. Much of the structure of human society has broken down, living standards and life expectancy have plummeted, malaria has spread northwards through Europe and is now a threat in England. This is obviously speculative and some readers may find this fictionalisation a bit jarring. However, the speculation is based on real science and I found the section to be valuable inasmuch as it forces the reader to consider the potential consequences of inaction.    

Finally, the author returns to the real world for the fifth section in which he outlines the steps we need to take to avoid the dystopian vision of the previous chapter. He offers chapters on raising awareness of the problem, greening our cities, transforming farming and rewilding. There are a host of practical suggestions and whilst some are certainly more realistic than others there is real hope here that we can avert this insect apocalypse if we act now. He concludes with a chapter on actions for all – national and local government, farmers and everyone else.  The actions for everyone include political engagement, changing the food we buy and where we buy it, joining conservation groups and making our gardens (if we have them) more nature friendly. Those with a particular interest in this area may also wish to consider the authors’ book, The Garden Jungle (D. Goulson, Vintage 2020)

Silent Earth is wide ranging in the ground that it covers, inevitably this means that it cannot cover each topic in great depth and some readers will be left wishing to know more about a particular topic, to that end the author provides an extensive further reading list. It would be hard to say that I enjoyed this book given the environmental devastation that it portrays, however, I did find it deeply engaging, the kind of book I didn’t want to put down. I would warmly recommend it to anyone interested in insects, the environment and the future habitability of our planet.