Some authors defend genetic uniformity of Great Atlantic scallop along the species distribution within British Isles, Ireland and France with the exception of a population in Mulroy Bay in Ireland (e.g. Beaumont et al., 1993; Wilding et al., 1997; Beaumont and Gjedrem, 2007) and the existence of two reproductively distinct populations in the Eastern (VIIe) and Western English Channel (VIId) (Pawson, 1995). Heipel et al. (1998) showed the existence of genetic heterogeneity in open-waters. Tully et al. (2006) studied larval dispersion and found some evidence of distinction populations in the Eastern Irish Sea and South Bristol Channel, but recommended further studies.
In 2013, the Scallop Assessment Working Group of ICES, “with a focus on defining a common approach to the assessment of stocks”, identified stock units (groups) of Great Atlantic scallop within each ICES area gathering the most recent data on population structure and other biological parameters from surveys, fishing effort and landings (ICES, 2013). The Marine Management Organization (MMO) also reports landings per ICES area, so here we complemented the information of both entities. These profiles may undergo restructuring in the future as new information comes to light.

ICES division VIIa: Northern Ireland, Isle of Man and Tuskar
ICES division VIIe,h: Cornwal
ICES division VIIf: Bristol Channel
ICES division VIIg: Celtic Sea