Thank you for the question.
There are two main factors, which stem mainly from policies implemented by the Department of Fisheries and Oceans. The first is the rationalization plans, most of which were implemented between the late 1990s and the 2010s in various fisheries. This rationalization essentially consisted of buying back existing licences in order to eliminate them. In some cases, this increased the quotas associated with each licence and improved the profitability of fishing enterprises. However, it has also had the undesirable effect of concentrating ownership of fishing licences.
The other factor is the shift in many fisheries from competitive fishing to individual transferable quotas. With those, fishing licences are attached to a set quantity of the resource to be harvested. This has increased the value of licences and led to a buy-back of licences among fishers, contributing to the concentration of licence ownership we see today.
I would like to point out that the rationalization plans and the move to individual transferable quotas are not necessarily inadequate, but they've had undesirable consequences on the concentration of ownership of licences, which in turn leads to problems with wealth redistribution and succession planning.