The biology and ecology of giant kelp forests.

This remarkable book is the biography of a single species, the ultimate ecological engineer in coastal seas. Giant kelp is not only a keystone species but also, where it occurs, much of the arch. Unlike most biographies, this is largely a scientific review: of Macrocystis pyrifera, its environment, and the ecosystems it makes possible. It is nonetheless extremely readable and never reads like a textbook. Unlike many reviewers (and unlike for some previous scientific book reviews I have written), I read the whole book and enjoyed the experience. It is as comprehensive as could conceivably be attempted, with almost 400 pages and over 1000 references. The text is interspersed with some fascinating insights from two close colleagues who have spent their careers working in these systems. These include explaining why giant kelp is ‘essentially a ‘‘weed’’’ and commenting that ‘about the only thing common among the giant kelp forests of the world is giant kelp itself’. There are 20 pages of descriptive accounts of different giant kelp communities, from Alaska to Baja California to the sub-Antarctic. They downplay the similarity with other ‘forests’, noting that ‘there truly is no terrestrial analogue of Macrocystis’. I particularly like the phrase ‘informed surmisal’. Their enjoyment in the writing comes across particularly in the history section and with the inclusion of memorable quotes and poetry. The species has a huge biogeographic range, across a multitude of marine provinces in both hemispheres and most of the world’s oceans, and as such the book should grace the shelf of all seaweed biologists and is highly recommended to other phycologists/marine biologists. If you are unfortunate enough not to have Macrocystis in your marine flora, you can still learn enormous amounts about inshore ecosystems and seaweeds and their environment from this book. The treatment is far from purely ecological, fully covering topics such as taxonomy, physiology, resource use, management and conservation, all within a clearly organised framework. The text is divided into four major sections on biology (90 pages), ecology (111 pages), use and management (68 pages) and global change and the future (32 pages). The literature is fully up to date and is gleaned from both primary and ‘grey’ sources, which led this reader, on a number of occasions, to wonder why such interesting and important findings remained in the latter category. One important use of this sort of comprehensive treatment is to resurrect such useful and cryptic information, including older literature which has not been superceded. It is interesting to note that 10 first authors are responsible for around 14% of the voluminous literature. The authors cope with the relatively recent idea that Macrocystis constitutes a single species by referring to what were previously species as ‘ecomorphs’, and they note that most work has been carried out on the ‘pyrifera’ ecomorph. Where information on aspects of biology is not available, they have included data from close relatives (e.g. the action of sex pheromones). It is perhaps surprising that there has been rather a lack of research on gametophytes of the species. Background information is often included on a topic to put the giant kelp data in context (e.g. on light in the sea). When searching for a topic which could, perhaps, have been documented in more detail, all I could think of was ecological economics. Although resources associated with giant kelp forests are fully presented and discussed, I wondered if any attempt has been made to calculate the overall economic impact of having Macrocystis off a coastline. It is indeed a pleasure to read the very informed opinion that ‘giant kelp forests are largely thriving’ and that ‘giant kelp populations themselves seem to be mostly intact’. The document is excellently edited, and, although the quality of the photograph printing could have been improved, all figures are clear and legible. The authors begin with a quote from Sir Joseph Dalton Hooker, predicting that such a book on Macrocystis ‘might be instructively filled’ but that these topics ‘constitute so extensive a field of research that the mind of a philosopher might shrink from the task of describing them’. Schiel and Foster have proved him wrong 168 years later.