How do we find dark vessels on the ocean?
International fishing involves some really big numbers. There are an estimated 4.6 million fishing vessels in the world. Most of these are small and local, but there are around 64,000 large vessels (24 m or longer) that operate in marine waters. Oceans cover 70% of the Earth and over 80% of the Southern Hemisphere. These are enormous areas to monitor. Seafood is a valued commodity, so how do we ensure that marine fishing is sustainable, responsible and regulated?
Starboard Maritime Intelligence
Dr Moritz Lehmann is Senior Scientist with Xerra Earth Observation Institute and Adjunct Senior Research Fellow at the University of Waikato. He explains how the Starboard software platform analyses information from satellites to monitor marine vessels and investigate their activities.
Jargon alert:
AIS: automatic identification systems (AIS) are used by ships to automatically provide their positions, identification and additional information to other ships and to coastal authorities.
Questions for discussion:
In what ways does Starboard® Maritime Intelligence help to monitor the activities of maritime vessels?
Why does Starboard choose to use multiple satellites to detect dark vessels?
What myth about satellites does Moritz bust?
Tracking vessels with automatic identification systems (AIS)
International waters are governed by the International Maritime Organization (IMO). The IMO requires all large ships to use an automatic identification system (AIS). AIS uses the vessel’s GPS or sensor built in to the AIS unit to transmit information including:
the vessel’s name, unique marine identity number and call sign
the type of vessel (fishing, cargo or passenger)
the vessel’s size
the vessel’s position on the sea
its course of travel and speed.
The AIS broadcasts the vessel’s position continuously – every 2–12 seconds – in order to avoid collisions at sea. Satellites pick up this information and relay it to ground stations, so even vessels in remote parts of the ocean are tracked.
AIS is also used by smaller craft. More than 400,000 AIS devices broadcast their vessels’ identities and locations annually.
Dark vessels
Vessels that do not want to be tracked switch off their AIS systems. They ‘go dark’ and are known as dark vessels. It is estimated that illegal and/or unregistered fishing vessels cost the global economy up to NZ$36 billion per year. Dark vessels are not limited to fishers. The ships may also be involved in transferring illegal goods or smuggling drugs or people.
Protecting our territorial waters and our fish species
Countries that border the sea have territorial waters. A very long time ago, this distance was 3 nautical miles (about 5.5 km) – the range of a cannon shot! In more modern times, the distance was 12 nautical miles (nmi) until 1982 when the United Nations established an international framework to create exclusive economic zones (EEZ) that stretch 200 nmi from the coastline.
Before the change to an EEZ, most of New Zealand’s commercial fishing was inshore within the 12 nmi range. The ocean beyond that was fished – uncontrolled – mostly by Japanese, Taiwanese, Korean and Soviet fishing vessels. Once the EEZ was established, New Zealand’s zone grew to more than 4 million km².
Exclusive economic zone
New Zealand’s exclusive economic zone extends 200 nautical miles (370 kilometres) beyond our offshore islands, giving the country a zone of 4 million square kilometres.
Key
NZ EEZ: NZ’s Exclusive Economic Zone
NZ OLECS: Outer Limits of the Extended Continental Shelf
The New Zealand Government introduced the Quota Management System in 1986 to protect and manage fishing areas and fish stocks. Commercial fishers are required to have a permit. They must also provide reports on lots of things including fish catch numbers, non-fish species or protected fish species, disposal, processing and landing and report on monthly harvest returns. Prior to this system, it was difficult for authorities to limit the number of commercial fish species that were caught.
The New Zealand Government has also signed international treaties and agreements to manage international fisheries and/or areas of the ocean.
New technology to help monitor the seas
The area within New Zealand’s EEZ is truly vast. In addition to managing fisheries, it’s also important to monitor marine protected areas and help with maritime emergencies. Satellite technologies have been a game changer in helping to monitor and manage the seas.
Xerra Earth Observation Institute has developed Starboard® Maritime Intelligence, a software platform that helps New Zealand and other countries monitor their national waters for activities like illegal fishing and dark vessels. Starboard combines data from AIS, satellites and computer models to analyse and investigate vessels and marine areas of interest. Starboard tracks where vessels have travelled, where they’ve docked and their movements near other ships.
Xerra uses satellites that have synthetic aperture radar (SAR) instruments on board. SAR emits radar waves that strike the steel surface of a vessel and then ping back to the satellite. SAR has real advantages over optical imagery (photos) – it isn’t blocked by clouds and it does not require someone to be able to see a vessel amongst the camouflaged background of the waves.
Dark vessels satellite mission
Some fishing vessels try to hide in the vast ocean by turning off their location-transmitting devices, fishing where they think no one can see them. They are known as ‘dark vessels’. Satellite and radar technology is being used to protect our oceans from this type of criminal behaviour.
This animated video is part of the Build a satellite interactive. To find out more about using satellites to track dark vessels fishing illegally, see the article How do we find dark fishing vessels on the ocean? then follow up with the activity Analysing satellite data for finding dark vessels.
Build a satellite to find dark vessels
Have a go at building a fit-for-purpose satellite to be able to catch these illegal fishing vessels! Choose the ‘Dark fishing vessels’ scenario. Once you’ve received the SAR data in ©Starboard, use this activity to analyse whether any dark vessels are operating in this part of the Tasman Sea.
Build a satellite
This interactive simulation is designed to develop students’ understanding of satellites and their usefulness with real-life research in Aotearoa New Zealand. The simulation requires users to build their knowledge and understanding about the requirements of each mission along with the satellite components needed to successfully launch a satellite that is fit for the mission’s purpose.
The simulation has three missions:
Find dark vessels fishing illegally
Track an albatross population
Monitor Earth movements
At each stage, there is access to a help button and links to additional resources that will support student learning in order to make accurate decisions throughout the satellite build and launch.
Simulation instructions
Click and drag components onto the satellite outline. Components can be added and removed. You will need to select all of the essential components as well as choose the correct payload component for your mission. Choosing the wrong payload means your satellite will not be able to collect data. Hover your mouse or finger over and select the three dots on each component to find out more information about its purpose.
Select a suitable orbit for your satellite’s mission. Choosing the wrong orbit means your satellite won’t be able to collect data.
For optimal viewing, use landscape orientation when using a tablet or iPad.
This is a simulation, so please note there may be small inaccuracies and satellite components and orbits are not to scale.
See the activity Build a satellite for a mission for a mission for additional support in using this interactive simulation.
Related content
These resources provide helpful background information.
Read more about building satellites.
Discover more about using satellites to track:
Activity ideas
Use the data the satellites collect during the simulation to analyse:
albatross nesting sites on a Chatham Islands sea stack
slow slip Earth movements near the East Coast’s Māhia Peninsula.
Consider doing the activity Interpreting observations from satellite images prior to these activities. It introduces strategies that are useful when interpreting satellite images.
Acknowledgement
This resource has been produced with funding from the Ministry of Business, Innovation and Employment and the support of the New Zealand Space Agency.
Rights: Crown copyright
Ministry of Business, Innovation and Employment and the New Zealand Space Agency
The New Zealand Space Agency, part of the Ministry of Business, Innovation and Employment, is the lead government agency for space policy, regulation and sector development.
Activity ideas
In the Fisheries role-play activity, students take on the role of a stakeholder in New Zealand fisheries. In their role, they decide whether they agree or disagree with the statement ‘there are plenty of fish in the sea’.
Useful links
The Office of the Prime Minister’s Chief Science Advisor reports on commercial fisheries in 2020.
Visit the Ministry for s website for maps of New Zealand fisheries and information about international fisheries management.
Read about the work of Xerra and Starboard Maritime Intelligence.
Watch Starboard Maritime Intelligence’s video Uncover hidden maritime activity with Starboard.
news article and video looking the success of Xerra, in detecting up to 100 dark vessels during a Pacific fishing surveillance operation.
Acknowledgement
This resource has been produced with funding from the Ministry of Business, n and Employment and the support of the New Zealand Space Agency.
Ministry of Business, Innovation and Employment and the New Zealand Space Agency
The New Zealand Space Agency, part of the Ministry of Business, Innovation and Employment, is the lead government agency for space policy, regulation and sector development.
