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Video is courtesy of Discovery Shark Week.

We are excited that the Argos satellite system is playing such an integral role in illegal fishing and catching those responsible. 

The diver in the middle of the image is carrying a RIFFE speargun and an Argos satellite tag attached to the end.

Image courtesy of Johnny Friday

Argos satellite tag locations when the shark breaches the water.

A lonely fish swims in the background while the team gets ready to tag a reef shark.

Image courtesy of Johnny Friday

Written by: Thomas Gray

CLS America, Inc.

Material and images courtesy of Patric Douglas, Discovery Shark Week, and all those involved in the project.

Collecte Localisation Satellites (CLS) is the only provider in the world for the Argos System. Argos is a satellite-based system which collects, processes and disseminates environmental data from fixed and mobile platforms worldwide.


The system was established in 1978 and since that time, it has provided data to environmental research and protection communities that, in many cases, was otherwise unobtainable. Many remote automatic weather stations report via Argos. Argos is a key component of many global research programs including: Tropical Ocean-Global Atmosphere program (TOGA), Tagging of Pacific Pelagics (TOPP), World Ocean Circulation Experiment (WOCE), Argo, and others.


It is the only system that is used to track shark migration! #SharkWeek


Each month, there are 22,000 active transmitters, 8,000 of which are used in animal tracking, and over 100 countries utilize the Argos system. Argos continues to serve as only tool for tracking long distance movements of both coastal and oceanic species.


Patric Douglas noted, “As the Executive Producer of Shark Week’s "Nuclear Sharks,” my team gamed out a number of scenarios for our shark [pop-up satellite] tags. Much to our surprise we lost 55% of the sample group to illegal fishing vessels. IUU (illegal, underreported and unregulated fisheries) is a trending and global problem; the Marshall Islands need additional support from the global community if they are to combat this ongoing problem within their massive sanctuary. The global conservation community should take note and take action to protect these huge investments in our oceans.”


Without the help from CLS and CLS America, Patric’s group could never have unearthed this knowledge.


An important thing to consider is that Argos transmitters are only used for environmental research; therefore, fisherman cannot attach these GPS-like devices to animals to then learn where they go in order to exploit a particular resource. However, what we have learned through use of the system is that fisherman are utilizing areas that have been designated as sanctuaries harvesting illegal catch! "The system is broken and illegal fisheries are laughing all the way to the bank," Patric Douglas, executive producer of "Nuclear Sharks, told Discovery News.


What makes the Marshall Islands challenging is its remoteness; the islands are three times the size of California but in the middle of the ocean. Their study species, reef sharks, are not pelagic (ie: they do not make long migrations); therefore, studying their movement becomes complicated and requires the appropriate technologies.


The satellite data from these tags showed that more than half of the sharks immediately moved west which is not normal behavior. Darcy Bradley, University of California Santa Barbara, reviewed the data. She reported, “The tags were certainly not on sharks: the traveling speed was far too fast and the tags were clearly at the surface. The speed and direction of movement also allowed me to rule out the possibility that tags were freely drifting.” She added, “It seemed that nine of the 15 tags were probably on boats, the sharks had likely been illegally fished, and a project with an ecological objective had suddenly become something entirely different.”


These tags, manufactured by California-based Desert Star Systems, continued to track the illegally fished sharks to ports in Guam and the Philippines. The group strongly suspects that these sharks were harvested and killed for their fins, which are utilized in the flavorless shark fin soup.


These fishing vessels are equipped with Automated Identification Systems which are meant to track and identify watercraft; however, prior research shows that it is not hard for a vessel to turn off this equipment in effect becoming a ghost ship. Douglas said that he has learned that these ghost ships will often work together, meet at various points in their routes, to offload cargo on other ships in attempts to mask their movement and patterns.


He expects that illegal fishing heightens in late October when the trade-winds strengthen allowing fisherman to save up to 30 percent on fuel costs.


Philippe Cousteau, who aided in the project, and colleagues reminded us, "As we saw in the Marshall Islands, even after man destroyed everything in its path with nuclear bombs, nature was able to bounce back. Nature is resilient and, if left alone, she will flourish. We, as humans, just have to ask ourselves if we will give her that chance."

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