In Britain and Ireland there are about ten times more species of solitary bee than bumblebee and honeybee combined, yet the solitary bees tend to be ignored and we know much less about them. However, they are a fascinating, attractive and diverse group that can be found easily in a wide range of habitats, both urban and rural, and they are important as pollinators. They are easy to study and are certainly no less interesting than bumblebees and honeybees. The main reason for the lack of awareness of solitary bees is probably that for over 100 years and until very recently there was no easily available guide to all the species. The publication in 2015 of a Field Guide to the Bees of Great Britain and Ireland by Falk and Lewington at last allowed anyone with an interest to make reliable identifications of solitary bees. However, identification of species can be daunting to the beginner. This Naturalist's Handbook provides an introduction to the natural history, ecology and conservation of solitary bees, together with an easy-to-use key to genera, which can act as a stepping-stone to the use of a comprehensive key to species. I hope that this book will encourage more people to study solitary bees.

The more they are studied, the more we shall know about them and the better we shall be able to conserve them for the future. Surprisingly, ex-industrial brown-field sites can provide some of the best nesting sites for solitary bees, which means that solitary bees can be studied and protected, even in the centre of cities. This Naturalist's Handbook on solitary bees is a very welcome addition to the series, complementing the existing titles on bumblebees (no. 6), solitary wasps (no. 3) and ants (no. 24). William D.J.

Kirk, July 2016.