Although this may look like an old-fashioned shirt collar made out of sand, it is actually an egg case of the Moon Snail and contains around 300,000 eggs. From April to September, when the female Moon Snail is ready to lay her eggs, she buries herself in the sand. Gathering the sand close to her shell, she exudes a gelatinous mixture embedded with her eggs, hardening the sand into a rubber-like collar. Wen the collar is finished, she pushes it upward and it appears like magic on the surface of the ocean floor. The whole process takes about 20 – 40 minutes. The embedded eggs soon hatch into larvae as the collar degenerates. The larvae join other floating zooplankton until they are ready to settle down and grow into Moon Snails.
This Moon Snail Collar can be found in the Tidal Treasures display at the Natural History Centre.
Photo by Barb Biagi.