Throughout its distribution, Nephrops is limited to muddy habitat and requires sediment with a silt & clay content of between 10–100% to excavate its burrows, and this means that the distribution of suitable sediment defines the species distribution. Adult Nephrops only undertake very small-scale movements (a few 100 m) but larval transfer may occur between separate mud patches in some areas. In the Farn Deeps area, the Nephrops stock inhabits a large continuous area of muddy sediment extending North from 54°45’–54°35’N and 0°40’–1°30’N with smaller patches to the east and west. The extent of the mud covers the following statistical rectangles: 38–40 E8–E9; 37E9 Division 27.4.b (Central North Sea), off the northeast coast of England. The assessed ground is defined by a polygon that encompasses suitable sediment and known fishing tracks (from VMS) (ICES 2019).  The UK fleet has accounted for virtually all landings (≥ 98%) from the Farn Deeps. The Farn Deeps fishery is essentially a winter fishery commencing in September and running through to March (ICES 2022).

Differences in N. norvegicus population demographic structure among geographical sectors, as well as in total mortality, appear to be highly related to different exploitation levels (Abelló et al. 2002).

Low levels of differentiation were found between Norway lobster populations and there were no signs of an Atlantic–Mediterranean divide or of an isolation-by-distance scheme of differentiation (Stamatis et al. 2004).

Stocks are assessed at a Functional Unit (FU) level. Each FU corresponds to a specific habitat area. However, the units are managed at ICES Division level. Thus, Nephrops management areas fall within the TAC regime of the European CFP, although allocated TACs do not coincide totally with the Functional Units (ICES 2023).