The Great Eggcase Hunt


Do you know about the Shark Trust’s “Great Eggcase Hunt”? It aims to get as many people as possible hunting for eggcases that have either been washed ashore, or are found by divers and snorkelers underwater.

In recent decades, several species of shark, skate and ray around the British coast have dramatically declined in numbers. The empty eggcases (or mermaid’s purses) are an easily accessible source of information on the whereabouts of potential nursery grounds and can provide a better understanding of species abundance and distribution.

Here are 10 things you might not know about eggs in the sea - in numbers...

1 in 1000 - Typically the number of turtle eggs that survive through to maturity

15 years – how long egg wrack can live on our shores 

20 ft long - the length of the fried egg jellyfish’s tentacles

53 months – the total time a deep sea octopus has been observed brooding eggs 

70kg – the amount of sand and gravel black bream have been known to move to make their nests that protect their eggs. 

200 species of pipefish - the male pipefish has a specifically designed area in the tail or a pouch (depending on sub-species) to carry eggs.

220m – the deepest an egg case has been found from the ghost shark

1500 or more – the number of eggs a male seahorse carries in his pouch

£20,000 for 1kg of ‘Almas’, the most expensive caviar in the world, produced from the eggs of a rare albino sturgeon between 60-100 years old. 

Millions of eggs – released by corals in mass synchronised spawning events

For more information about the Shark Trust, visit

This article is part of our "Did You Know?" series.

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Suzannah Walmsley

Business Development

(Fisheries & Aquaculture)

+44 (0) 2380 711 858


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