Oyster Drill

Ocenebra erinacea


With a very jagged, snail-like shell, Oyster Drills are whelks, living below the low tide mark where they feed on oysters by boring through their shells with their sharp proboscis.

How to identify

Whelks are more pointed than periwinkles. The Oyster Drill is unmistakeable, being much rougher and more jagged in outline than any other whelks. It is often yellow or white in colour, with brown markings.

Where to find it

Found on rocky shores predominately in the west and south-west of the UK.


When to find it

  • January
  • February
  • March
  • April
  • May
  • June
  • July
  • August
  • September
  • October
  • November
  • December

How can people help

In the 1970s and 80s, whelks and other gastropod populations were seriously affected by the use of chemical anti-fouling paints on boat hulls containing tributyl-tin (TBTs). These paints caused females to become male, leading to a decline in reproduction. The use of TBTs is now controlled, but chemical pollution can still be an issue for our marine animals, particularly as it builds up through the food chain. The Wildlife Trusts are working with fishermen, researchers, politicians and local people towards a vision of 'Living Seas', where marine wildlife thrives. This work has recently had a massive boost with the passing of the Marine Bill, promising sustainable development of the UK's marine environment. Do your bit for our Living Seas by supporting your local Wildlife Trust.

Species information

Common name
Oyster Drill
Latin name
Ocenebra erinacea
Aquatic gastropods (e.g. sea snails)
Length: up to 10cm
Conservation status