The present book reflects the results from six years of monthly monitoring of the waterbirds in the most important wetlands of Bulgaria - the Bourgas Lakes. Such a monitoring is carried out for the first time in the country. The book is divided in two parts. The first part consists of a comprehensive review of the literature data, the status, the numbers, the breeding and the seasonal dynamics of 149 waterbird species, which are recorded in the Bourgas Lakes during the monitoring. The information for each species is presented in text tables, graphs and maps. In the second part, a thorough look at the four Bourgas Lakes with their specific characteristics is made. The top ten most abundant species for each lake are presented. The changes in species composition and numbers are traced for different months, seasons, years and last century as a whole. The book is written by the members of the Bourgas Wetland Project, implemented for the period 1996-2004 as a part of Bulgarian-Swiss Biodiversity Conservation Programme. It will be especially useful for anyone interested in ornithology, birdwatching, nature conservation, wetland management and monitoring.