SPECIES SURVEYING AND MONITORING

Chapter 10 of this part gives an introduction to the theory and principles of population survey and monitoring and describes the general methods used to estimate population size. These methods will often need to be tailored to suit the requirements of the species being studied; this information is provided in the sections on species groups.

Chapters 11–26 contain details of the standard methods used to survey each group of species, from fungi to mammals. Attributes that provide an indication of the condition of species in each group are identified at the start of each chapter, and methodologies for monitoring these attributes are described; references for further information are listed at the end of the book. Specific recommendations and current survey and monitoring protocols for selected species that occur in the UK and appear on Annex II of the EU Habitats and Species Directive (apart from vagrant and introduced species) are described at the ends of these chapters.

Each section contains a table summarising the methods covered. A brief summary of the following points is given:

• the recommended groups for which the method is appropriate;

• the type of data that the method provides (i.e. presence/absence, population size, etc.);

• the efficiency of the method, i.e. the combined quantity and quality of data produced in relation to cost and effort;

• the precision obtainable;

• the likely nature of any inherent bias; and

• advantages and disadvantages.

Each method is then described in three sections: (1) principles; (2) field methods; and (3) data analysis and interpretation.