Gulls and Plovers: the ecology and behaviour of mixed-species feeding groups. By C. J. Barnard and D. B. A. Thompson. Croom Helm, London, 1985. 302 pages; 14 black-and-white plates; 10 line-drawings. £25.00.This book--the first of Croom Helm's projected series 'Studies in Behavioural Adaptations' (editor Dr John Lazarus)--is aimed mainly at those interested in behavioural ecology, 'from advanced undergraduate to research worker and lecturer*. Will it, then, appeal to the average reader of British Birds? Well, the first point to make is that it deals with a fascinating subject: the feeding strategies of a gull (the Black-headed Larus ridibundus) and two plovers (the Lapwing Vanellus vanellus and the Golden Plover Pluvialis apricaria) on pastureland, and the association between the three species, including exploitation of the Lapwing by the other two, and kleptoparasitism by the gull on both the plovers: it steals their worms. All this is treated in great detail against the background of current ideas on behavioural ecology in general and on optimal foraging and flock dynamics in particular, thus usefully integrating two topics that are usually studied separately and providing a valuable introduction to a wide field of research about which the ordinary birdwatcher may know rather little. Anyone interested in bird behaviour and intent on self-education will, therefore, profit from reading this book. Whether he will enjoy it in the process is another matter for an easy 'good' read it is not, rather a very long scientific paper with a prolificity of all the usual paraphernalia of the genre—tables, formulae, graphs, histograms, and so on—together with a few drawings of the birds themselves and a number of photographs of variable standard. But the effort is well worth the making, aided by a series of resumes and summaries and a closing 'overview'