Finding washed up eggcases on the beach joys folks of every age. You also call them mermaid’s purses. They are egg capsules of cartilage fishes, which include sharks, skates, rays and chimaeras.
These capsules commonly wash up to many coasts around the world, after they are empty. Usually you find black or brown item, that feels leathery or rough. Some shark eggcases even wash up with a living embryo inside.
How to Find and Identify Mermaid’s Purses
When the embryo uses all the yolk, it comes out from the capsule with full body form.
Identify them can be hard. But looking at the size, form and various features help to know which species laid it. For instance, size and form of the purse separate each species.
Except the eggs of bullhead sharks, they usually have rectangular form. At each corner commonly are projections, called horns. Capsules without outer layer can be smooth and bright, rough or striated.
Shark eggs have curlier tendrils, while skates and rays have horns at each end. Occasionally cat shark capsules wash up with their curly tendrils all tangled together. The dogfish produce the smallest eggcases, that folks most commonly find.
If you find dried and empty capsule, you place it in bowl with seawater or fresh water. Rehydrating them makes identification easier. Home you can simply do some science to prepare them.
For help to identify, it is essential to use a local identification guide. Are good resources for marine enthusiasts and citizen scientists. Folks use an Eggcase ID Guide or an Eggcase ID Key to narrow down choices step by step.
An app for iPhone and Android also exist with step-by-step ID key for identify easily on the beach. A Shark Egg Identification Chart helps find of features, size and form. Taking part in the Great Eggcase Hunt of the Shark Trust is another way help to preserve sharks and rays by means of find and record capsules on the coast.