The barnacle is one of many things I was encountering in abundance on rocky shores and knew almost nothing about. As my rockpool-hopping adventures continued, I was inspired to find out as much as I could about the varied inhabitants of the Cornish coastline, especially life as easily overlooked as barnacles. Here are a few fun barnacle-facts:
- A barnacle is an arthropod, an invertebrate with an external skeleton (exoskeleton), and is closely related to crabs and lobsters.
- Once attached to a suitable location, the barnacle is in place for life. Completely immobile, it is only going to move if predated or perhaps shoved out of the way by an inconsiderate limpet.
- We will mostly encounter barnacles closed up and preserving moisture in intertidal zones and rockpools. However, when feeding, their legs appear, wafting in the surrounding water to catch micro-organisms or detritus.
- While on the subject of feeding… one species, the goose barnacle, is also something of a delicacy in Portugal and Spain.
- The majority of barnacles are hermaphrodites, having both male and female reproductive organs. Self-fertilisation is possible, but rare. Instead, barnacles will most often reach out to neighbours to reproduce.
And the final factoid:
- They can also make rather splendid hats, as this shore crab kindly demonstrates: