The Asian Shore Crab reaches the mainland UK

The Asian Shore Crab (Hemigrapsus sanguineus) reaches the mainland UK.

Two sightings of the non-native Asian shore crab (Hemigrapsus sanguineus) have been recorded in the mainland UK for the first time ever. The two records in the past month have come from completely different parts of the UK – one from Barry Island in Wales and the other from Kent. These records have raised concern from the Shore Thing team as this is a non-native species for the UK and may affect populations of our native species, common shore crab (Carcinus maenas) and edible crab (Cancer pagurus), through distribution overlap and competition.

Species change for the Shore Thing timed species search…

Due to the 2 recent Hemigrapsus sanguineus records in the UK, the Shore Thing project has decided to make a vital change in the timed species search. The Green Ormer (Haliotis tuberculata) has been removed as a species in the timed species search and replaced with the Asian shore crab (Hemigrapsus sanguineus). We believe this is an important change as records of the Green Ormer only come in from the Channel Islands, where it is a native species, and recording the Asian shore crab starting from this early stage will be incredibly significant when monitoring its spread through the UK. If you find any Hemigrapsus sanguineus during a timed species search then please take a photo and send it in so the Shore Thing team is able to verify and validate this record.

Here is an updated survey form for future use.

Asian shore crab (Hemigrapsus sanguineus) ID and background

Distribution and background: This crab is native to the Western Pacific Ocean in Russia, China, Korea, Hong Kong and the Japanese archipelago. This species has then spread to the US and Europe (brought in by ships), and has now in 2014 reached the UK mainland. Found in intertidal rocky shore, in rock pools and under rocks and boulders.
ID: Relatively small crab with adults carapace size ranging from 35mm to 42mm. Distinct square shaped carapace with 3 spines on each side of carapace. Colour ranges from orange-brown to green-purple and their legs are light and dark banded.
Link: A good link to more information on this species can be found here

Survey dates…

If any surveys have been completed recently, please upload your data here and then send back your recording forms to: The Shore Thing, MarLIN, The Laboratory, Citadel Hill, Plymouth. PL1 2PB so that verification can take place ready for upload to the NBN Gateway

If you require any further information contact Fiona at the Marine Biological Association

Other Non Native Species?

If you are interested in recording other Non Native Species or in finding out more information about them, then please visit the RISC project pages on the GB Non Native Species Information Portal