As a seafood lover and a conscientious consumer, I try to know where my tuna comes from. I want to know that the fish I buy is not only good for me but also being caught in a way that keeps the ocean healthy, too. When fishing vessels use a registration number to identify themselves, seafood processors and distributers can take note of exactly who caught the fish, as well as where and how they caught it. They can pass that information on to retailers and consumers like us. It’s a simple enough concept that increases retailer and consumer confidence in what we are buying. That’s the kind of traceability we all want, and it starts with the vessels on the water. If transparency methods like ‘can codes,’ which would allow a consumer to trace the tuna in the can back to the vessel that caught it, are ever going to live up to their full potential, it is essential that all large-scale vessels are outfitted with unique and permanent numbers first.

Why is this important? Because illegally caught fish is making it’s way onto our shelves. How much exactly is hard to say but even a small percentage is too much. Illegal fishing contributes to overfishing, often harms the environment and many times means stealing fish from poor coastal countries in Africa or small Island nations in the Pacific.

Thousands of vessels fish for tuna all around the globe. With so many boats on the water moving in and out of a variety of global ports, it is critical that every vessel have a unique and permanent number to distinguish it from all others even if it changes owners or country registry. Outfitting all boats with unique vessel identification number (UVI) such as those issued by the International Maritime Organization (IMO) allows for the unprecedented ability to track vessel behavior, good or bad, so that buyers know which boats to buy from, and so that enforcement bodies can do their job more effectively. Of the four main inter-governmental bodies that oversee tropical tuna fishing, three adopted measures last year that require vessels operating in their waters to obtain an IMO number. The fourth one, the Inter-American Tropical Tuna Commission (IATTC), which manages the Eastern Pacific, just recently followed suit at their annual meeting in Peru.

This progress is due in part to the efforts of the International Seafood Sustainability Foundation (ISSF). Companies that participate in ISSF comprise close to 75 percent of the global tuna purchasing power, and they have pledged to buy only from vessels with IMO numbers and to not buy from vessels identified by regional management bodies (RFMOs) as having previously engaged in illegal fishing.

That has sent a powerful message – vessels can either adapt by coming online or they can lose out on a lot of prospective buyers. Since 2011, we’ve witnessed a 76 percent spike in the number of tuna fishing vessels that have publically available, registered IMO numbers.

ISSF has taken this to the next level. Through its ProActive Vessel Register (PVR) – an audited database of tuna vessels available to the public – boat owners can prove their legality as well as other steps they are taking above and beyond legal requirements to openly demonstrate their level of commitment to sustainable practices.

In recent years, vessel owners have voluntarily added data on their boats to the PVR and this has helped the rule-makers in the RFMOs add regulatory pressure on those that have not by requiring the use of IMO numbers for vessels that fish or do business within their jurisdiction.

Just like a car’s VIN number or license plate can help police track the activity of vehicles on the road, IMO numbers help RFMOs and national governments track and enforce against vessels fishing illegally, or failing to meet certain regional standards for sustainability. Efforts from ISSF, their peer organizations and RFMOs to make the supply chain more transparent and to dissuade bad behavior are progressing well. Today, significantly more vessels are registered IMO numbers than a few short years ago, but IUU fishing remains a serious problem for the industry and for the millions of people who rely on tuna for jobs, and food, and it will remain so until we can transparently trace catches from the sandwich all the way back to the boat.

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