Join the Great Eggcase Hunt

If you’re hitting the beach, make sure you keep your eyes peeled for evidence of sharks in British waters. You may not see the classic image of a dorsal fin moving through the water, but you could find a Mermaid’s Purse mixed in amongst the seaweed in the strandline. So what does a mermaid keep in her purse? Well it’s a baby shark, skate or ray!

There are over 30 species of shark and over 20 skate and ray living in British waters (http://www.sharktrust.org/en/british_sharks), and some of them reproduce by laying these tough leathery eggcases, or Mermaid’s Purses. The eggcase acts as a life support machine and provides everything needed for the young to grow. Depending on the species, it can take between 5-9 months for the young to develop all of its features and then it will be ready to leave the safety of the eggcase. The young will force its way out through an opening between the horns (or tendrils) and emerge as a fully formed miniature version of the adult, completely independent and requiring no parental care.

The empty eggcases are much lighter and when dislodged from their resting places are often brought ashore by the tide. If you find one, use the Shark Trust’s Great Eggcase Hunt identification guide (www.sharktrust.org/en/GEH_resources) to figure out what species your eggcase belongs to, and then submit your record to the project using the online recording form or the smartphone app! Over 120,000 records have been submitted so far, giving us a good idea of where different species occur. The southwest coastline offers fantastic diversity and in Devon or Cornwall you may find as many as nine species (if you’re really lucky!). Further along the coast in West Sussex, you could find hundreds of eggcases but it will likely be from just one or two species. Head up to the northeast coast of England and very few eggcases seem to be recorded at all! Even further north to Orkney and around to the west coast of Scotland and you’ll find the last stronghold for the Critically Endangered species, the Flapper Skate, the eggcases of which you will rarely find anywhere else.

So get involved and help the Shark Trust out! You don’t have to be a scientist to be a citizen scientist.
www.eggcase.org

 

The Shark Trust is the leading shark conservation organisation committed to safeguarding the future of global shark populations through positive change.