Corella eumyota was originally described from Valparaiso in Chile and is native to the southern hemisphere, where it has a circumpolar distribution within the temperate and sub-polar regions - Chile, Antarctic Peninsula, South Africa, Australia, New Zealand.
Extreme clumping behaviour can make Corella eumyota a nuisance. © JDD Bishop
Its first report in the northern hemisphere was in 2002, on pontoons in two marinas in Brittany, France. It was subsequently reported during a trawl survey in Ría de Vigo, north-west Spain, in 2003.
The first records in the British Isles were from rapid assessment surveys of marinas along the south coast of England in 2004 and in Ireland in 2005 and 2006.
Recent rapid assessment surveys revealed its widespread occurrence along the Atlantic seaboard of the Iberian Peninsula.