colonial hydroid


The high seas of Storm Brian have brought some unusual visitors to Penparcau and Aberystwyth in West Wales.  The first to arrive was the jellyfish-like colonial hydroid Portuguese man o’ war.  This animal is more at home in the warmer waters of the Atlantic and Indian oceans, but was pushed off course by the extreme weather event.  Their venomous tentacles can be up to 30m long, and even those washed up dead on our coast can have a very painful sting, possibly fatal to children or animals. 

Having these exotic animals arrive on our local beach was an amazing thrill and caused huge debate and interest locally.  Our first sighting was on the 6th October 2017, and they were still present by the 30th of that month.  The Marine Conservation Society appealed for records and we were pleased to add ours to the attempt to track the progress of these creatures around our shores.

The second exciting visitor is actually a resident of Cardigan Bay waters, but rarely seen on land, the Curled Octopus.  Again, in response to the stormy sea conditions, they have been seen on Aberystwyth and Penparcau beaches.  The above animal was luckily found alive by a local man, and safely returned to the sea.  We were approached by the Beach Stuff website, who spotted our octopus records on Facebook, and asked to use them in an Interactive Map of stranded Octopus around the UK that they then shared with the Marine Conservation Society.  Social media has been a very useful tool for tracking these animals in almost real time as they move around our coast.


Noble ‘Coral’ (Stylaster nobilis

…a species of colonial Stylasterid hydroid which is endemic to the South African coast from the Atlantic Coast of the Cape Peninsula to Port Elizabeth. Like the unrelated hard corals, noble corals colonies are predatory ans will feed on a variety of plankton which are dispatched by stinging nematocytes.


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Image(s): Peter Southwood 

“Minature aeolis” (Tenellia adspersa)

Also sometimes known as the “lagoon sea slug”, the miniature aeolis is a small species of Tergipedid nudibranch, which is distrusted from the Northeastern Atlantic to the Mediterranean Sea, and Caspian Sea. Miniature aeolis are known to inhabit coastal intertidal and sublittoral zones, and feed mainly on hydroid colonies. 


Animalia-Mollusca-Gastropoda-Heterobranchia-Euthyneura-Nudipleura-Nudipleura-Nudibranchia-Dexiarchia-Cladobranchia-Aeolidida-Fionoidea-Tergipedidae-Tenellia-T. adspersa

Image: USGS

Snowdrop Hydroid (Gattya humilis)

…a delicate species of colonial Halopterdid hydroid which is endemic to an area off the south African coast, ranging from Northern Namibia to KwaZulu-Natal. Snowdrop hydroids typically occur from the littoral zone to ~70 m (230 ft) under water, where they are usually found growing on coralline algae or weed. 


Animalia-Cnidaria-Hydrozoa-Hydroidolina-Leptothecata-Plumularoioidea-Halopterididae-Gattya-G. humilis

Image: Seascapeza