Blue Marlin Management Updates

Annual meetings of the International Commission for the Conservation of Atlantic Tunas and the Western and Central Pacific Fisheries Commission concluded in late 2018. Both of these regional fisheries bodies are charged with the international management of highly migratory species in their respective bodies of water and last year, marlin stocks were the item of discussion for both commissions.

In the Pacific, the status of the western central North Pacific Ocean striped marlin stock was on the table at the 15th Regular Session of the WCPFC. According to the 2015 assessment, the WCNPO stock had experienced a long-term decline  in population biomass and the stock is currently overfished and is also experiencing overfishing. Spawning stock biomass is estimated at 1,094 metric tons, or just 39 percent of the biomass necessary to achieve maximum sustainable yield. Fishing mortality on the stock also has been very high and the stock has been experiencing overfishing since 1977, with the exception of two years. The WCPFC Scientific Committee noted that in order for the stock to rebuild, the catch needed to be reduced to less than 2,850 mt.

So, what happened at the meeting? Not a whole lot. The commission noted that it was unable to agree on the designation of North Pacific striped marlin as a northern stock. It also acknowledged that North Pacific striped marlin is experiencing overfishing and is overfished, stating that the work plan for 2018-19 includes completing a benchmark North Pacific striped marlin assessment, which will be presented at the next meeting of the scientific committee in August, 2019. The commission also accepted the recommendations of the scientific committee to develop a rebuilding plan as a matter of priority.

On the Atlantic side, the results of the 2018 blue marlin assessment put this stock on the negotiating table at the 21st special meeting of ICCAT. The 2018 assessment indicated blue marlin are experiencing overfishing and/or have been overfished since 1990. In 2012, the commission took steps aimed at rebuilding blue marlin through a measure that was subsequently carried forward in 2015. Most notably, these measures included implementing a 2,000 mt total allowable catch — establishing country-specific quotas that require member nations with non-industrial fisheries to provide information on their data-collection programs, in addition to reporting estimates of live and dead discards.

While these measures had the intention of rebuilding blue marlin, the ICCAT Standing Committee on Research and Statistics voiced concern that they might not be sufficient to end overfishing and rebuild the stock. This was demonstrated in the 2011 assessment indicating that a TAC of 2000 mt would only give the stock a 32 percent chance of ending overfishing and rebuilding by 2026. Annual landings since the measures went into effect typically exceeded the 2,000 mt TAC by as much as 800 mt, and the 2018 assessment indicated that current measures have not been sufficient to end overfishing and make appreciable strides in rebuilding the stock. In addition, the lack of data on live and dead discards as well as catch from artisanal fleets continues to be an issue.

If you were hoping for some good news from the meeting, I’m sad to disappoint.

Read More Conservation Here.

The United States put forth a proposal that included measures to increase blue marlin post-release survival and strengthen data collection by way of circle-hook use and electronic monitoring on pelagic longline vessels, coupled with a requirement to release live marlin in these fisheries. These measures — and others that benefit blue marlin — are already in effect in the United States, but did not gain broad international support. As a result, ICCAT punted yet again and extended the current blue marlin management measures for one year, which also coincides with the next completed white marlin assessment.