The New Zealand arrow squid fishery is based on two related species. Nototodarus gouldi is generally found around mainland New Zealand north of the Subtropical Convergence, whereas N. sloanii is found in and to the south of the convergence zone. The two species are both found off the northern part of the South Island west coast (Fisheries New Zealand (FNZ) 2023, and references cited therein). They are also known as arrow squid.

Except for the Sub-Antarctic islands fishery (SQU 6T), for which a separate TACC is set, the two species are managed as a single area (SQU 1) although, uniquely, there are separate TACCs set for catch from jigging (SQU 1J) and catch by any method (SQU 1T) (Fisheries New Zealand (FNZ) 2023). Due to both their short life span and fishery characteristics, there is no proper assessment of these management units.

This profile is for the SQU6T region, where the fishery is almost entirely a trawl fishery (Fisheries New Zealand (FNZ) 2023). 

Recent in-depth investigation of the spatial and temporal structure of the fisheries and survey data available including catch and effort, length, maturity, and copulation data allowed the formulation/confirmation of biological hypotheses (Mormedes and Dunn 2023). Five potential stocks / sub-stocks of arrow squid were delineated as follows:
• North of 36° S: mostly N. gouldi
• West coast 36° S to 45.5° S: mixture of both species
• East coast 36° S to 45.5° S: N. sloanii with different spawning time to south of 45.5° S
• South of 45.5° S: N. sloanii with different spawning times to the east coast
• South of 49.5° S: N. sloanii which might be linked south of 45.5° S but presents an additional main length cohort

However, the authors note that research identification of the two species could be uncertain as research staff may have been instructed to code as NOG in the north, NOS in the south, and SQU in between. Further understanding is required, which needs specialists to identify the two species