Weimerskirch, H., Collet, J., Corbeau, A., Pajot, A., Hoarau, F., Marteau, C., … & Patrick, S. C. (2020). Ocean sentinel albatrosses locate illegal vessels and provide the first estimate of the extent of nondeclared fishing. Proceedings of the National Academy of Sciences, 117(6), 3006-3014.
lllegal, Unreported, and Unregulated Fishing
Scientists are constantly working to discover ways to innovate and improve measures for protecting biodiversity. One of the biggest threats to biodiversity in our oceans is the occurrence of illegal, unreported, and unregulated fishing that typically happens in international waters – ocean water that is further than 200 miles off the shore or outside of exclusive economic zones (EEZ). Illegal fishing leads to major consequences such as over-fished stocks and accidental catch of threatened or endangered species.
Currently, two types of technologies are being utilized to track fishing vessels both in EEZs and in international waters. Vessel monitoring systems are primarily used within EEZs and are regulated by nations, while Automatic Identification Systems (AIS) are required by international law on vessels of a certain size and type. AIS was designed as a tool to prevent vessels from colliding with one another, but it can be turned off by the operator of the vessel. This ability is ripe for misuse by illegal fishers, which are thought to use this feature often. Although there are many organizations working to track fishing efforts in international waters using AIS data, having consistent and real-time data is limited.
The Ocean Sentinel
Tracking marine animals has been a useful way to collect data, especially when determining which areas are being used for habitat or reproduction. In recent years, animals such as sea turtles, sea birds, and marine mammals have been fitted with bio-loggers to collect this data and transmit data instantly to researchers using satellites. A new logger has been developed that can detect radar emissions from boats and shows the interaction between fishing vessels and sea birds. Building off of this tool, researchers H. Weimerskirch et. al. created a conservation concept that uses the logger information to improve surveillance and enforcement of illegal fishing vessels by using albatrosses.
Albatrosses are seabirds which have a wide habitat range and as ocean-patrollers, are naturally drawn to fishing vessels, detecting them from up to 30 km away. Equipped with loggers, albatrosses can provide information on the distribution of fisheries across EEZ and international waters, as well as instantaneously providing this data to researchers and relevant authorities regarding the location of fishing vessels.
Wandering albatross (Diomedea exulans). Photo by Bernard Spragg
Studying Ocean Sentinels
The researchers designed a study to evaluate the potential for Ocean Sentinels (OS) as an operational conservation tool. They aimed to compare the OS concept to the other existing surveillance systems, such as VMS and AIS. Further, they planned to estimate the proportion of vessels illegally deactivating their AIS by comparing the data from AIS to the data from the bio-loggers.
Albatrosses were fitted with loggers that recorded the location of the bird and scanned for radar emissions for 1.5 minutes every 15 minutes. Every hour, a summary of this data was provided to the researchers. AIS data was also collected on a daily basis, and the two datasets (bird and AIS) were merged to associate bird location to an AIS location within 5 km.
Albatrosses are naturally drawn to fishing vessels.
Photo by Ed Dunens.
Between December 1, 2018 and June 1, 2019, there were a total of 632,333 GPS locations of albatrosses, together with 5,108 radar detections in the southern Indian Ocean. The 5,108 radar detections represented interactions with 353 different boats. Among the 353 detections of vessels, over 25% had no AIS signal within 30 km. In international waters, this percentage increased to over 35%, indicating that more vessels were not using AIS in international waters than within EEZs.
The Big Picture
The first results of the OS concept study clearly show that it is possible to use animals to improve surveillance in isolated areas of the ocean. They also allowed the researchers to estimate the proportion of boats operating without AIS in both the EEZ and in international waters, which would otherwise be undetected. The larger implications of this study show that the OS concept has the potential to protect biodiversity in the long term.