Robert Thompson / Dog whelk (Nucella lapillus) and Common barnacle (Semibalanus balanoides) on rock. Mill Quarter Bay, Killard Point National Nature Reserve, Strangford, County Down, Northern Ireland. February.

SCOTLAND: The Big Picture / Common whelk (Buccinum undatum) on maerl (Corallinales) bed, a priority marine feature. Within a Marine Protected Area, Shetland, Scotland, UK, September.

SCOTLAND: The Big Picture / Common whelk (Buccinum undatum) laying eggs, Loch Creran, Argyll and Bute, Scotland, UK, November. Small repro only.

Alex Hyde / Eggs of Common whelk (Buccinum undatum) on beach. Anglesey, Wales, UK. December.

Ann & Steve Toon / Hermit crab (Pagurus bernhardus) emering from whelk, Boulmer, Northumberland, UK, April

Sue Daly / Eggs of Common whelk (Buccinum undatum) on beach, Sark, British Channel Islands.

Sue Daly / Eggs of Common whelk (Buccinum undatum) on seaweed washed up on beach, Sark, British Channel Islands.

Sue Daly / Common whelk (Buccinum undatum) Bouley Bay, Jersey, British Channel Islands.

Nick Upton / Egg masses of Common whelk (Buccinum undatum) washed up on high water mark alongside dried out Bladder wrack fronds (Fucus vesiculosus), Rhossili, The Gower peninsula, Wales, UK, June.

Nick Upton / Dog whelk (Nucella lapillus), a predator of barnacles, on rocks encrusted with Common barnacles / Northern rock barnacles (Semibalanus balanoides) exposed at low tide, with seaweed, a rock pool and th...

Nick Upton / Head on view of Common Hermit crab (Pagurus bernhardus) in a Dog whelk shell crawling over floor of a rockpool. Rhossili, The Gower Peninsula, UK, July.

Nick Upton / Common brittle star (Ophiothrix fragilis) moving over floor of rockpool encrusted with red algae past Flat / Purple Top shell (Gibbula umbilicalis), Rough periwinkle (Littorina saxatilis) and Thick-li...