Warning follows whale vomit find on Morecambe beach
The RNLI is warning treasure hunters to take care after a rare piece of whale vomit was found on Morecambe beach.
Ken Wilman found the ambergris while walking his dog on the beach.
The substance, which is found in the digestive system of sperm whales, is valuable and used in perfume.
Mike Guy, Morecambe's lifeboat operations manager, said: "The tide comes in so very quickly that it catches people unaware, even people that know it."
Ambergris is a natural excrement thought to be used by the whale as a digestion aid and is expelled from its abdomen often while hundreds of miles away from land.
Referring to conditions on Morecambe beach, Mr Guy said: "It can very quickly turn into soft sand and even quicksand and the tide will surround you.
"We're really worried about people just wandering off on the beach searching for ambergris.
"They're very, very unlikely to find any because it's very rare.
"We want people to be very aware of the tide and if they're in any sort of doubt about the conditions where they are walking, get in touch with the coastguard."
The hard beaks of giant squid, a main source of food for sperm whales, have often been found inside lumps of ambergris.
Initially, it is a soft, foul-smelling matter that floats on the ocean but through exposure to the sun and the salt water over years it turns into a smooth lump of compact rock which feels waxy and has a sweet smell.
It is still used in perfumes, although many perfume makers now use a synthetic version.