African waters are home to three of the four most productive marine ecosystems on Earth: Canary Current, Benguela Current, and Somali Coastal Current upwelling systems. This enormous marine resource attracts industrial fishing fleets from countries around the world – with more fleets arriving into these bountiful waters every year.

For Africa’s coastal communities, small-scale fisheries are crucial for sustaining and supporting both food and economic security. Now, the intense foreign fishing is a growing concern. More boats means more maritime safety issues (e.g., vessel collision) and more resource competition between the local small-scale fisheries and foreign industrial fleets.

The Third United Nations Conference on the Law of the Sea (1982) stipulated that a coastal State has jurisdiction over the exploration and exploitation of marine resources in its adjacent section of the continental shelf, a band extending 200 nautical miles from the shore. In Africa’s Exclusive Economic Zones (EEZs), over 6 million metric tons of fish and 15 billion U.S. dollars went towards the African gross domestic product in 2011.

With stark warning about the impact of climate change from the recent IPCC report, now more than ever there is a pressing need to sustainably manage Africa’s precious marine resources. Traditionally, fishing efforts are monitored using global fishing vessel registries and self-reported fishing data from the Food and Agriculture Organization of the United Nations (FOA). But the data quality of traditional methods is subject to each nation’s fisheries monitoring and surveillance system. Inadequate information and misreporting frequently occur in African nations. With so many fishing vessels off this continents vast coast, some wishing to stay unseen, we need to find new ways of monitoring maritime activites here and elsewhere on Earth. And we found the answer in space.

Automatic Identification System (AIS) satellite data is a new technology that can track the fishing footprint within African EEZs. Orginally developed for preventing vessel collision, AIS automatically tracks the geographic location of individual vessels at high spatial resolution in near real time. The system is now installed on most active fishing vessels larger than 24 meters and is widely adopted for many smaller vessels – a useful tool for keeping an eye on who goes where in the ocean.

But first, to be sure, we wanted to test it out. The location of industrial fishing activity detected by AIS aligns very well with fisheries catch data across African EEZs. The consistency between AIS-derived fishing effort and fisheries catch shows that AIS data can provide a complementary and reliable means for monitoring the location of major industrial fishing activities. This is very encouraging, especially as African fisheries are desperately in need of this information for better fisheries management. So, we took a deeper look at the data to see what it revealled.

Intense Industrialized Foreign Fishing

There has been controversy over foreign fishing in African waters, but there is yet to be a comprehensive assessment of how they act – where do they go, how often and how long for? Our research shows that foreign flagged vessels from all over the world fish off Africa’s dynamic and rich coast. Spain, Taiwan, Italy, Japan, China, and South Korea are the main fishers, making up half of the total fishing time that occurred in this part of the ocean. It just so happens that these foreign fishing states are also the main players in global industrial fishing efforts and high-seas fishing.

(Image credit: School of Marine Science and Policy, University of Delaware)

The most popular fishing grounds were located within the Canary Current and Benguela Current upwelling systems, likely due to the high productivity in these waters. But we also found something rather disturbing happening in these regions.

Also fishing here many fleets flagged to open registry states (aka. Flag of Convenience), such as Belize and St. Vincent & Grenadines. Open registry states allow a ship's owners to register a merchant ship to a country other than that of the ship's owners. Flag of Convenience ships have long been linked to illegal, unreported, and unregulated (IUU) fishing.

(Image credit: School of Marine Science and Policy, University of Delaware)

It’s concerning to find so many open registry fleets fishing in Canary Current and the Benguela Current since a prior study by Belhabib, Sumaila, & Le Billon (2019) showed that most fish stocks in these ecosystems are either fully or over-exploited, largely due to intensive legal and illegal industrial fishing.

What attracts foreign fleets?

While the high marine productivity is a big lure for foreign fishers, there are several other factors likely influencing where they fish within Africa’s EEZs.

Under the United Nations’ Convention on Law of the Sea, foreign countries require a fishing permit to access fisheries in the EEZ of other countries. African countries have a short-term economic incentive to grant foreign countries access to fish in their waters. Western African nations with abundant fishery resources often have agreements with foreign countries, allowing them to exploit marine resources in exchange for development aid and financial and infrastructure compensation. This explains why the waters of Western Sahara and Mauritania in West Africa were fished by the highest number (>30) of foreign countries.

We also found that some countries take advantage of geographic vicinity and predominantly fish in their neighboring African waters. For example, almost all Italian fishing efforts occurred in Tunisian waters, which means the Tunisian EEZ has a particularly high foreign fishing time. But its not always about the location.

Southwest Indian Ocean, which encompasses Madagascar, Réunion, Seychelle, and Mauritius, is an increasingly important fishing ground for tuna. Tuna is a highly valuable species among some Asian communities, like Japan, South Korea, and Taiwan. Our study identified the African waters within Southwest Indian Ocean are the hot fishing spots of these fishers. In other words, the resources of specific fish stocks (tuna, in this case) determine where those vessels fished.

Shining a Light on Dark Fishing Activity

African waters are among the most susceptible waters to IUU fishing in the world. We often rely on the reporting data from the vessels themselves to confirm what they are catching, thus making it difficult to take IUU into account. The AIS data can show where and how long the vessels were fishing and, by jointly assessing the AIS tracking data and the reported catch data, can provide new insight into potential IUU fishing activities.

We used Namibia, an African country in that region, as a case study.

Namibia has a relatively good surveillance system - they require every fleet who fishes in their waters to land in their domestic docks. This means there should be consistency between who reported fishing and catch there, and the fishing vessels detected by the AIS. However, even with Namibian’s strict regulations, we find that some fishing fleets did not follow the rules, which would result in under-estimation of catches.

Twenty fishing entities were identified fishing in Namibian waters from the AIS records, but not all of these detected flag states were recorded having catches in Namibian waters. Specifically, fleets of St. Vincent & the Grenadines, an open registry state, spent longest time among all foreign flag states in Namibian water, but their catch was not recorded in the database, neither was other open registry states like Comoros and Belize.

The discrepancy between detected fishing and reported catches points to IUU fishing in African waters. Namibia has one of the few relatively well-managed fisheries in the world. With this in mind, it is likely that similar unreported fishing occurs not only in many other African EEZs, but globally. At least now there is a tool which – used alongisde other methods – can help track industrial fishing activities for better fisheries management, and hunt for those who wish to remain hidden. Because, afterall, it’s not just the fish who’s life depends upon it.

This feature appeared in Environment, Coastal & Offshore (ECO) Magazine's 2021 Autumn edition, to read more access the magazine here.