| Reference no. | Harms, J., 1993 |
| Ecosystem | North Sea |
| Status | native |
| Abundance | |
| Lifestage | adults |
| Regional database | |
| Remarks | Declining populations around Heligoland from 1984-2002 may be due to continued TBT (a liquid biocide in anti-fouling paint) pollution from ships. Also, population threats related to oil spills such as exposure to heavy metals and dispersants used in clean-ups; and shell collection for the tourist trade (Ref. 88171). |