Peacock’s tail seaweed, Padina pavonica
Peacock’s tail seaweed is a brown alga that grows on selected rocky shores along the south coast of England. It has fan shaped fronds with a feather like appearance which can be light brown to lime green in colour.
Padina pavonica is a warmer water species which is why its distribution is limited to southern England. It does especially well in the rockpools of Kimmeridge Bay as the water here is shallow and therefore warms up quickly; also there are fewer large seaweeds, such as kelp, that would shade out the more delicate peacock’s tail seaweed. However with climate change it is likely that we may see this species extending its range northwards as sea temperatures rise due to climate change.
Peacock’s tail seaweed is nationally scarce which is why it’s a Biodiversity Action Plan Species. We need people to report sightings of this distinctive seaweed so that we can map its distribution and protect it to ensure it doesn’t disappear from the U.K. This annually growing seaweed dies back every autumn and reappears the following spring, so now is the perfect time to look out for it on the seashore.
Sea hares, Aplysia punctata
Aplysia punctata is a type of sea slug found throughout British Seas. Sea hares may look more like slugs than snails at first glance but they actually have a reduced shell hidden inside their fleshy body as it is related to other species of sea snails called Gastropods. They can grow up to 20cm long and are found mainly in shallow waters.
Their colour can vary between green, brown, red or even purple. It is thought that their colour depends on what kind of seaweed they graze on. Young sea hares tend to feed on red seaweeds that are found in slightly deeper waters, whereas the adults move into shallower water at this time of year to breed and eat more of the brown and green seaweeds found there, giving them a different colouration. Their eggs can be found in tangled threads wrapped around seaweeds and are sometimes seen in the intertidal zone.
Common prawns, Palaemon serratus
Common prawns, as the name suggests, are fairly common around the whole of the U.K. and beyond. They are found in many different habitats including rockpools, amongst seagrass, in estuaries and in water up to 40m deep. Their bodies are translucent with darker red/brown banding and their legs have brown and yellow stripes.
Common prawns breed between November and June and the female then carries up to 4000 eggs with her for 4 months until they hatch. At this time of year the rockpools are filled with tiny juvenile prawns. This species are scavengers, feeding on any remains of dead or decaying animals they can find, as well as small planktonic animals. The occurrence of these young prawns is timed to coincide with an annual boom in the amount of food available for them. This helps to achieve the highest possible survival rates. Common prawns are not threatened, however they face high natural predation as they are food for a huge range of other species and form an important part of the food chain in intertidal areas.
Peacock tail seaweed © Carole Elliott
Sea Hare © Julie Hatcher
Common prawns © Julie Hatcher