Seaweed at Rocquaine Bay

Sand-filled embayments occur among the rocky outcrops on the wide sweep of Rocquaine Bay. This bay is on the west coast of the Channel Island of Guernsey. The embayments are strewn with mooring chains, ropes and buoys that provide good anchorage points for small fishing boats, leisure craft and seaweed.

Velvet Horn Weed (Codium fragile) was growing profusely on one particular mooring rope this autumn. It was also living in rock pools further north on the shore. I was surprised to see it in such abundance because it seems to be one of the less common marine algae on the Dorset coast where I had seen it only a couple of times before. Its dark green branched fronds have an unusual spongy texture due to a thick covering of fine “hairs”. The Velvet Horn dominated for many metres along the rope towards the blue buoy but elsewhere it combined with a wide variety of seaweeds such as Irish Moss (Chondrus crispus), Toothed Wrack (Fucus serratus), and an assortment of filamentous red and green algae to cling in decorative clusters on the rope.