Mackerel, Management, and Uncertainty

by NewsBot on November 25, 2016 - 8:15pm

Globally, fisheries have been experiencing crises as a result of an increase in the number of boats actively exploiting fish stocks, and a resultant decrease in the size of fish populations. An article that I read recently touches on this subject and specifically addresses the state of Atlantic Canada’s mackerel fishery. The article, titled “mackerel fishery closed unexpectedly, leaving some fishermen short bait: P.E.I. Fishermen's Association wants better way to track actual catch numbers” by Laura Chapin was published on in 2016 and describes the effects of the early closure of Atlantic Canada’s inshore commercial mackerel fishery in Prince Edward Island (P.E.I).

The fishery’s closure occurred on October 14th,2016 and marks the first early closure in the fishery’s history, occurring a full two-and-a-half months earlier than normal. Chapin reached out to Chuck White, a member of the P.E.I Fishermen’s Association who holds the chair responsible for the mackerel fishery. White says that the effect of this early closure is that many P.E.I fishermen will likely be obliged to purchase bait for lobster fishing come spring, a costlier alternative to relying on mackerel that they would typically catch and then freeze prior to the start of winter. Eastern Canada’s 2015 mackerel quota of 8,000 tonnes, which was not reached that year, remained the same for 2016, instilling in White a hope that the mackerel population is recovering from decline. The decision to close the fishery was made by Canada’s Department of Fisheries and Oceans (DFO), and was based on mackerel catch data collected from other areas of Atlantic Canada and Quebec that indicated depleted stocks.

Uncertainty is a common theme in all resource management scenarios. Lacking accurate data, resource managers are regularly forced to make management decisions in the face of uncertainty and I think that the DFO’s decision to close the mackerel fishery early is a good example of such a decision. They explained in an email to the CBC that accurate catch numbers are difficult to obtain since some fishermen, those in P.E.I being no exception, are negligent in reporting accurate catch numbers. While the DFO has stated that there is a chance, albeit small, of the inshore mackerel fishery reopening if catch numbers achieved by its offshore counterpart fall below the allowable catch, many P.E.I fishermen have already removed their boats from the water for the season.

Natural resources can be divided into two categories: stock resources, whose supply can be depleted permanently, and flow resources, whose supply can be replaced. Mackerel, along with most fish, exist as renewable flow resources, and as such, have the potential to be sustainably harvested. In order to prevent mackerel from becoming a stock resource, which can occur for any renewable flow resource if harvesting rates exceed regeneration rates, the DFO lowered mackerel catch quotas a number of years ago.  They claim that closing the mackerel fishery early this year will allow them to ensure that the mackerel populations are rebuilding, and that whether or not their populations are rebuilding will be determined by conducting a stock assessment this coming winter.

To me, the conservative decision made by the DFO to close the mackerel fishery early makes sense when you consider that it is more difficult to calculate the resource base, defined as the total quantity of a substance or property within the geosystem, for a stock than a flow resource. This is because the availability of a stock resource is static whereas that of a flow resource is dynamic, meaning that there is greater uncertainty associated with estimates of a flow resource’s base. Essentially, populations are in constant flux, so the DFO would rather err on the side of caution in this case, rather than risking a population collapse.

White stresses that he’d like to see cooperation between the DFO and P.E.I fishermen this winter in order to develop a method for improving the accuracy of catch information, thereby reducing uncertainty in the future. This would be a form of co-management, where both government and resource users participate in the decision making process regarding how a resource should be managed, and can help to alleviate conflicts that might normally arise between fishermen and the DFO. Such a method will take time to develop, as each group has different ideas of how data should be logged. This past year, the submission of self-reported logs, either weekly or daily, was suggested by P.E.I fishermen, whereas the DFO would like to see catches being reported daily by dockside monitors, the latter being a strategy that White says would be challenging due to the disproportionate ratio of fishing boats to dockside monitors. While upwards of 1,200 boats make up the mackerel fishery, it is uncommon to have more than one dockside monitor, and the fact that these boats tend to dock simultaneously makes monitoring catches accurately that much more difficult. Hopefully P.E.I fishermen and the DFO can reach an agreement, but only time will tell.

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