Monsters of the (not very) deep

02 February 2010

The moon has been huge for the last few days. In fact, sometimes it seemed to cast more light than the sun itself managed. And with the full moon come the spring tides: for a few days more water comes in, and more goes out, than normal. Areas of seabed that are usually safely covered up are exposed, giving us the chance to have a look at the bottom of the sea without going to the trouble getting in it.

At the bottom of Fuchsia’s beach is a particularly good spot on a very low tide: a land bridge forms between Tanera and one of the small islets in the bay (the imaginatively named ‘Eileen Mòr’ - Big Island), and this afternoon Rich and I went to have a look.

How extraordinary. In amongst the usual brown sandy mud and brown seaweed - sugar kelp and toothed wrack – lives a collection truly strange orange creatures. On top of rocks, colonies of petite pastel-orange volcanoes turretting. On the side of rocks, thick plastic-like orange glooping under its own weight, its rough surface studded with craters. In muddy puddles, gelatinous orange discs, themselves seemingly home to even stranger beasts. And all over the sandy mud bottom, little green 'daisy anemones' tuck themselves away. As with much of the natural world, particularly the under-water realm: everything so wonderfully odd you just couldn’t make it up.

We’ve worked out that the plastic-y mass is probably a ‘sea orange’; a type of ‘sponge’. Sponges are almost the simplest creatures in the animal kingdom: they simply draw in water through pores on their surface, collect anything food-like, and squirt it out again through the large vent on the surface. The other orange organisms might also be sponges, or perhaps sea squirts, which seem similar to sponges in that they take in water and squirt it out again but are, apparently, much more sophisticated. 

In a few hours they were safely enveloped by nutritious chilly water. Just a few of the brilliant beasts out there at the end of our garden. As the waters get warmer later in the year, the water's inhabitants will get even more amazingly strange...