The Pacific ocean covers approximately one-third of the Earth's surface. You could fit all the land in the world into the space it occupies – with room left over for an extra Canada. Put another way, it’s bigger than the surface of Mars.

Paul Hilton / GREENPEACE

Within it, there are vast tuna fishing areas, which shift as tuna migrate with the time of the year and changes in water temperature. 

On this trip we’ve been in the area managed by the Western and Central Pacific Fisheries Commission (WCPFC). This agreement, between 33 countries, covers almost 20% of the world’s surface - an area larger than the planet Mercury or roughly three times the size of Africa (take your pick).

Pacific island island nations have relatively small land area compared to their exclusive economic zones (EEZ), because an EEZ extends 200 nautical miles from the coast of a country (in theory, the reality can be complicated and politically controversial).  An extreme example is Kiribati with 810 square kilometers of land, and 3,550,000 square kilometers of water in its exclusive economic zone.  That’s a country with a land area smaller than Germany’s capital city, Berlin, but an EEZ larger than India’s. And one patrol boat to police it.


Finding things

It goes without saying that to find something the size of a fishing boat in the vastness of the Pacific is no easy task, even with modern technology. Countries and companies are also secretive about what fish is caught where, partly because this would give competitors information. 

Even fisheries scientists working on Pacific tuna fisheries have a hard time getting the full information they need (known as “operational level data”) from all the countries fishing in the region. Some hold back details or limit scientists’ access to information even though they are obliged to provide it.

All of this leads to a lot of mystery and confusion, especially about the situation on the high seas. A big part of what we’re doing is investigating and exposing what’s really happening out here. 

Here are some of the tools and tactics we’re using: 

Past experience and industry research – We’ve been doing this kind of work for over 10 years, and in that time built up a wealth of knowledge and personal contacts. Some of our team have worked in the tuna industry themselves, so have a useful perspective on finding fish and finding fishing fleets. 

Land based research team – Looking at everything from satellite photos  to marine registries to vessel tracking websites. Their importance can’t be underestimated.

Radar – Works well for spotting ships at up to about 40 km (25 miles). The Rainbow Warrior’s 55-meter tall masts (with the radar on top) help extend our range. But rain interferes with it, reducing the effective range. (Fortunately, it’s mostly clear skies in this part of the world.) 

Radio – Li Ang, one of our Chinese speaking crew members is often called to the radio to interpret conversations being broadcast in Mandarin or Taiwanese. It’s mostly tuna ship captains chit chatting – swapping recipes, comparing how many cigarettes they smoke, arguing when they get in each other’s way – but occasionally he picks up clues.

Lookout – We’re scanning the ocean with binoculars for things too small to pick up on radar like fish aggregating devices (FADS), fishing buoys, etc. And have spotted ships in the night by the reflection of their lights on low clouds over the horizon. 

Helicopter – The helicopter can cover much more ocean than our ship. It gives us two things: height (able to see farther the higher up) and range (it can cover a much bigger search area than the much slower Rainbow Warrior). It’s also good for going over to ships for a closer look.

Automatic Identification System (AIS) – Not all fishing vessels are required to have satellite tracking, but some do. AIS sends a signal with a unique identification number for each ship, plus location information. We can pick these signals up on the Rainbow Warrior, and our land team can search publicly available websites for ship tracking information. But sometimes fishing vessels don’t have them or turn theirs off, especially if they’re up to something dodgy.  

Fishing vessels in this region are also required to have a Vessel Monitoring System (VMS), but this data is only available to governments.

Guesswork and luck – Inevitably plays a role. Most of the fishing boats are faster than the Rainbow Warrior. To get a close look we have to either come across them when they’re fishing, or arrange to be in the right place at the right time (so they come to us). 

Paul Hilton / GREENPEACE

Still searching

One thing we’re finding is that there are clumps of long-line fishing vessels, of one nationality per group. (Purse seiners, which fish with nets, tend to work more independently.) What’s probably happening is a combination of fisheries prospecting (one ship finds a good spot and shares with its friends) and macro-politics (relationships between countries influencing where different ships want, or are permitted, to fish). This means fishing areas shift from year to year and month to month.

We’re in almost daily contact with stakeholders, regulators and allies to share this information. And it’s going to be incredibly valuable when Greenpeace fisheries experts attend upcoming Fisheries Commission meetings. To achieve a fair fisheries, we need to change the rules around fishing to give island states a bigger say in what’s happening to fish stocks in their part of the world.

We also need to transform the tuna industry into one that prioritizes long-term sustainability and fairness. And that’s where you come in.  Check out the tuna shopping guide for your country, share it with friends and family, talk about it online and with your local store manager. When tuna companies know their customers care, they make demands of their suppliers in response. This is already happening in some markets. So you can have a real impact, just by how you shop and by spreading the word.