Internal and external tagging methods are used for a mark-recapture study on lobsters at Helgoland (German Bight, North Sea). The visible implant fluorescent elastomer tag (VIE) is a colour tag and suitable for marking small (>3cm in total length) and adult lobsters. Colour tagged lobsters can be individually identified even more than five years later.
External numbered tags (T-bar anchors, polyethylene streamers) and internal transponder chips are applied for larger and adult lobsters. There is some risk of tag shedding related to moulting. Therefore, external tags can be used only for a short-term study. Additional marking by V-notches or holes in the tail fan can help to identify the animal
