Atlantic herring in this region are treated as a stock complex with a number of somewhat discrete spawning subunits contained within it. Because these subunits mix at times other than spawning, and because the site fidelity of spawning cannot be determined conclusively, they are treated as an aggregated unit. Within this unit are 4 main sub-stocks/management units:

1. SW Nova Scotia / Bay of Fundy spawning component
2. Offshore Scotian Shelf banks spawning component
3. Coastal (South Shore, Eastern Shore, and Cape Breton) Nova Scotia spawning component
4. SW New Brunswick migrant juveniles

Of these components, only the SW Nova Scotia / Bay of Fundy spawning component is considered in this profile (referred to as stock 4VWX by management body DFO). It is important to note that the SW New Brunswick migrant juveniles are reported in the assessment document, although they are actually considered part of the US stock.