• crabs
  • crabs
  • crabs


FSC Crabs AIDGAP covers all of the crabs of British coastal waters.

The guide will enable anybody to identify all the ‘crabs’ of British sea shores. The key is designed to be used with living crabs in the field. Most identification characters are visible to the naked eye, although a x10 hand lens is useful with very small specimens.

No special specimen preparation is needed. And there is no need to kill the animal, nor extract it from its shell. The authors have tried to use non-technical language throughout. But where technical terms are unavoidable, explanatory figures and a glossary are given.

Crabs are crustaceans. They are common animals on the seashore, and are sometimes abundant. Most crabs are carnivores (especially of molluscs) and scavengers. Since they can run and swim, they are very mobile. At low tide they often shelter under large algae and stones.

This crabs guide is part of the FSC’s AIDGAP series (Aids to Identification in Difficult Groups of Animals and Plants). The aim of AIDGAP series is to produce accessible keys suitable for non-specialists from age 16+. Although written by specialists, all AIDGAP guides go through field tests in draft form. As with all guides in the series, the Crabs AIDGAP underwent extensive testing before publication, by beginners and specialists alike. The authors have revised the key in the light of the testers’ experience.

Accurate identification of specimens is an important part of biological fieldwork. Aside from popular groups, like wild flowers and butterflies, many other groups are neglected. Since 1976, the AIDGAP project has published over 40 straightforward identification keys to many different groups of plants, animals and other taxa. In many cases a new AIDGAP guide has led to an immediate upsurge in the number and spread of biological records.