Ideally, in any kind of fishery, when you assess or manage a fish stock, it is important to measure the mortality caused by fishing, to know precisely how much has been caught.
In the case of mackerel, there are several uncertainties that prevent us from having an accurate estimate: the bait fishery, the recreational fishery that occurs throughout Atlantic Canada, and the winter fishery in the United States, which catches some of the fish that spawn in the Gulf of St. Lawrence and are part of our stock.