Sponges

Several different species of sponges live around Lundy

Sponges are very simple colonial animals with a spongy appearance and there are numerous different growth forms. Some are encrusting (like the breadcrumb sponge), others are branching. Sponges use tiny openings to draw water inside themselves and filter out suspended food, such as plankton. The water is pumped through their structure and exits through large openings in their surface called oscula. Sponges are very slow-growing and fragile and they are easily damaged or destroyed by objects hitting them; such as lobster pots, divers' fins and fishing line.

Breadcrumb Sponge –Halichondria panicea

© Keith Hiscock

This common seashore species is highly variable in its encrusting forms however easily recognised by its striking green or yellow colour, and irregular surface structure pitted with oscula (holes) which take in and pass out water. This sponge is highly sensitive to desiccation, favouring sheltered shady crevices and it can take some exploring to find as it is often covered by the fronds of wracks where it remains moist while the tide goes out.


Elephants Ear Sponge

© Keith Hiscock

This animal lives in and around the kelp forests and down to a depth of about 20 m. It grows on the hard seabed and boulders in a wave-like encrusting form. The colour of this sponge is always grey or off-white and very often looks like an elephant’s ear or hide.


Yellow Boring Sponge

This sponge is the largest sponge in the Atlantic area and is highly visible as it forms large fleshy yellow masses often isolated on poorly inhabited rocks. It may reach 60 cm across, with clear pores visible over the structure of the sponge. The pores or oscules are at the end of small outgrowths mainly on the upper part of the animal. Deep living, it is found from the surface to 200 metres deep.

Lundy is owned by the National Trust and managed by the Landmark Trust.