I'd be following those shells, looking for some food!
Sandy grooves in amongst a piece of intertidal rocky coastline?
What a grand excuse to go poke around by myself.
Packed lunch, hot drink, place to sit.
Then, I could replace the lunch with a small stove!
Everything on our coast has been poisoned for years by Paralytic Shellfish Poisoning.
I believe it affects the filter feeders and 1 oyster is enough to kill a person.