This book is an ambitious ecological, geopolitical, and cultural history of the droppings of Pacific Ocean birds from the entry of Europeans into the ocean through to the aftermath of the hydrogen bomb tests in the 1950s. The book's argument has seven aspects: the geographical parameters; the story of the Pacific world; the agency of nature; the links between the Pacific world and the Industrial Revolution; the cultural influence of guano; the social groups involved in, and the ethical ramifications of, the production and consumption of guano; and the devastation wreaked by the atomic age. In narrating these aspects, the author seeks to reveal the extraordinary global influence of something so apparently inconspicuous as guano. These seven aspects are structured as nine chapters, each of them pivoting on a particular theme: the importance of nitrates and the guano by-product; environmental governance and the technocratic ideals of developmentalist projects; environmental degradation stemming from continuously rising living standards; and ‘the collision between the guano age and the atomic age’ (p. 22).

The argument of the book progresses in a broadly chronological manner. Chapter 2 covers the nineteenth-century Peruvian Guano Age, Chapter 3 the ‘neo’-ecological imperialism of Western capitalism, and Chapter 4 the impact of this imperialism on the environment of the Pacific islands. Chapter 5 fast-forwards to the twentieth century, opening the second half of the book, which reads more coherently, not only in terms of its content but also in how its content is treated. This second half addresses matters that are still topical, such as the pressure of population growth on agriculture productivity to meet growing demand for food and, in particular, higher protein foods (which, in turn, fuelled the production of fertilizers and guano). These went hand in hand with increasing technocratic intervention in the environment through developmentalist policies. The book thus bridges the transformation of the ‘agroecological systems’ caused by economic development and the nascent conservationist stance in contemporary politics and culture.

Without doubt, this is a work of erudition. It has a total of 788 footnotes, most of which contain multiple references, spread over 350 pages. At the same time, Cushman invokes The West Wing to illustrate the relationship between technocracy and politics (p. 139), refers to nondescript ‘Chinese mass-media icons of hunger and misery’ (p. 308), and gives details on the whereabouts of the son of one of his heroes, the Peruvian guano bird expert, conservationist, and marine scientist Enrique Ávila (p. 349, n. 52). These left this reader baffled as to their relevance. Furthermore, a complicated structure militates against the book's aims. Each chapter is headed by quotations from purportedly relevant material from different times; the main text of each chapter starts with an anecdote of an equally variegated nature. The link between these and the central argument of the chapter is seldom obvious. Unfortunately, this rhetorical strategy is pursued throughout the book.

Notwithstanding the book's title, the locus of the argument in every chapter moves freely within – and without – the Pacific Ocean. If there was a common driver in the multifarious history of guano (and nitrates and phosphates), it is obscured by the laboured eclecticism of Cushman's illustrations. Sometimes the determining factor appears to be climatic, such as the El Niño events that affect the reproductive capacity of fish which feed the birds from whom the guano is collected. Sometimes it appears to be the blind faith in the technology that humans deploy to maximize the economic returns from nature regardless of its sustainability. Yet the book is equivocal about whether it is markets that drive the biota or the other way round – or whether it is all contingent.

This equivocation is a problem because the author wishes to tackle the inherent tension between property rights and the ecosystem. But to do so requires engagement with the political economy of guano's production and use – and with environmental exploitation more broadly. Cushman's reluctance to engage with this is admitted in the treatment of imperialism and colonialism, where ‘to avoid … an additional level of complexity … [he] will not distinguish between those factors’ (p. 77, n. 1). Given the book's already very elaborate narrative structure, however, this caveat fails to convince. His views on ‘neo-ecological imperialism’, gesturing to Crosby's well-known thesis, are suggestive. But his attempt to characterize the expansionist and exploitative endeavours of the US, together with those of Australia, New Zealand, Peru, and Chile, as cases of neo-European imperialism is much less compelling. It is far-fetched to describe New Zealand or Chile as imperial powers in the nineteenth century (loose use of the term ‘informal imperialism’ does not strengthen his case). Broad references to ‘ethnocrats’ and ‘ecocrats’ – in opposition to ‘plutocrats’ and ‘technocrats’ – do not help us comprehend the role of human agency in the exploitation of the ecosystem. Similar woolliness is found in addressing the agency of humans (in marked contrast to the attention given to the ‘agency of nature’). So, for example, there is very little about the labour involved in different stages of the guano extraction and transformation (pp. 177–8), and almost nothing on land rights and ownership in the ‘input-intensive agriculture’, or on the production of explosives (p. 13), which are the main sources of demand for nitrates.

In the end, the ambition of a global ecological history of the droppings of Pacific Ocean birds becomes untenable and the line dividing this ambition from its actual realization as a collection of often fascinating vignettes wears very thin indeed. Where the book succeeds is in sampling a large number of environmental, geopolitical, and technological histories, and through offering valuable insights into the histories of scientific ideas, economics, and policies in different parts of the globe. Disappointingly, the central analytical threads that might have helped us make sense of the numerous agents and incidents presented, and thus evaluate the roles played by environmental and geographic factors, and the effects of technology and vested interests, are masked by an unnecessarily complicated narrative structure. Cushman's evident mastery of his subject will make particular sections of the book useful for a wide variety of readers who are in search of specific kinds of information. If only the author had maintained a sharper analytical focus and deployed a more streamlined narrative structure, this book could also have made a more direct contribution to global history. Sometimes less is more.