Wild Harris

Seasquirts: Rocky Seabed

If you have ever handled a rope on which sea squirts are growing you will know how they get their name. Out of water they look like boring lumps of slimy jelly, but there is a lot more to them rthan that. Each squirt has two pipes or syphons - one sucks water into the animal where it is strained to extract the food, and the other expels the strained water. 

Sea suirts have complex organs including a well developed digestive system, and most surprising of all they share 80% of our genes! Sea squirt larvae have a sort of backbone, which makes them close relatives of vertebrates. 

Most sea squirts grow as individual animals attached to a rock or other hard surface, but some grow in colonies, often forming sheets with flower-like patterns.

lightbulb.jpgLightbulb Seasquirt    (Photo: Paul Tyler)

The light bulb seasquirt occurs in small colonies. They also glow in the dark!

colonial 2.jpgColonial Seasquirts    (Photo: Sue Scott)

A close-up of 2 different kinds of colonial seasquirts. Each ‘petal’ in the flower-like pattern is in fact a single sea squirt. Colonies of these spread across flat surfaces on the seabed

pink seasquirt.jpgPink Seasquirts    (Photo: Paul Tyler)

Many sea squirts are solitary animals. You can clearly see the 2 syphons in this pink sea squirt - one to suck food-laden water in, the other to exhale it after straining out the food.

by Paul Tyler