Borth-y-Gest is a small Welsh Harbour village on the south side of the Llyn Peninsula, close to Porthmadog, overlooking the Glaslyn Estuary. It is a delightful place with its own special microclimate and a friendly atmosphere. Just along the coastal walk are a series of small bays and sandy beaches going round to White Rock Sands and eventually to Black Rock Sands. Washed up on the beaches near to the village were masses of jellyfish. I cannot remember seeing so many stranded jellyfish in one place before.
This Barrel jellyfish was one of many larger jellyfish scattered across the beaches, It is a common resident in UK waters and the food of choice of large marine turtles.
Another common species is this distinctive Compass jellyfish. The radiating lines on the dome make this an easy jellyfish to identify.
The Moon jellyfish was probably seen in the largest numbers. Some are clear, but mature specimens show the four loops of the gonads, a purple colour in this one. The colour of these structures ranges from blue to brick red.
A small number of Moon jellyfish had been stranded in rock pools. These animals will most likely survive when the tide comes in, carrying them back to sea.
This specimen of Catastylus sp. is a significantly large jellyfish at about 70 cm across the dome. This was the largest jellyfish on the beach. There were also a few smaller species that I could not identify.
When the tide is right and the jellyfish numbers are high, these wash up events are inevitable on such beaches. In biological terms they are not significant as there are very large numbers of jellyfish in the seas around the UK. However, it is still a sad event to see so many stranded and dead marine creatures on a beach.
PS. 20 July - a survey has identified that there is an abundance of jellyfish throughout the Irish Sea this year. The barrel jellyfish is in exceptionally high abundance. It appears that these conditions occur regularly every few years.