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Top predators play a key role in maintaining the health of open ocean ecosystems. Understanding how they relate to their environment is fundamental in order to monitor their populations and the state of the marine environment. White sharks, among others, have been tracked using Argos satellite telemetry, and their path compared with ocean eddies and meanders to study where they can feed in not-so-rich areas of the ocean.

How white sharks navigate with respect to ocean features

White sharks (Carcharodon carcharias) are among the top predators of the ocean (“Jaws”, in the movie, is supposed to be a white shark – albeit a gigantic one). Such a predator is often detected in the open ocean. There, phytoplankton, considered as the base of the food chain, is rather scarce, and mostly concentrated in eddies or meanders. These structures, about 50 to 200 km wide, are also known as “mesoscale” features to physical oceanographers.

Diving patterns

Two white sharks were fitted with surface Argos position tags, so as to have precise locations that made it possible to co-locate them with mesoscale features with sufficient accuracy. One of them also had a pop-up archival tag recording diving behavior allowing to link different diving patterns to different locations. Both sharks were located preferentially within eddies and meanders. In particular, they spent more time in the core of “anticyclonic” eddies (warmer than the surrounding ocean) than in their reverse version (colder). The double-tagged shark also showed a different diving behavior in the two kind of eddies, diving at 1000 m- 200 m (known as the “mesopelagic” or “twilight zone”) around the time of sunrise and sunset in the anticyclonic eddies more often. These patterns could be linked with the higher energetical need energy to regulate body temperature in a colder surrounding.

Protective measures

This type of knowledge can be used to better understand the behavior of animals, prioritize regions of the ocean that are particularly important for their foraging behavior, inform models and policies to design sustainable fishery policies and effective marine protected areas.

One of the sharks’ track overlaid on sea surface height anomalies from altimetry satellites (Credits Applied Physics Laboratory, University of Washington) (note that such maps can now be plotted for the last year using the “Met-Ocean” feature on Argos web)
One of the sharks’ track overlaid on sea surface height anomalies from altimetry satellites (Credits Applied Physics Laboratory, University of Washington) (note that such maps can now be plotted for the last year using the “Met-Ocean” feature on Argos web).


Photo: One of the tagged white shark (Credits OCEARCH)


  • Peter Gaube, Camrin D. Braun, Gareth L. Lawson, Dennis J. McGillicuddy Jr, Alice Della Penna, Gregory B. Skomal, Chris Fischer & Simon R. Thorrold, 2018: Mesoscale eddies influence the movements of mature female white sharks in the Gulf Stream and Sargasso Sea, https://doi.org/10.1038/s41598-018-25565-8


female Asian Houbara

23.10.2018 Birds tracking Satellite-tracking to create the demographic evidence-base for the sustainable management of hunted Asian Houbara

As Robert J. Burnside of the University of East Anglia explains in his presentation at the European User Conference on Argos Wildlife, the migratory Asian Houbara …

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A snowy owl (

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Tracking turtle brendan godley

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Photo showing animal with attached Argos transmitter on 9 February 2018 (Krista Hupman, NIWA)

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Sunfish tagged with an X-Tag at Eastern Taiwan. Credits Tuna and Billfish Tagging Project in Taiwan

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Allan Mee, of the Golden Eagle Trust, Norwegian Institute for Nature Research, presents his work reintroducing white-tailed sea eagles, at the European User Conference for Argos Wildlife (EUCAW). As he explains, white-tailed Sea Eagle (WTSE) Haliaeetus albicilla became extinct in Ireland in…
Tropical tuna tagging Uruguay-P.Miller-2017

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Loggerhead turtle equipped with a satellite tag. Source: Miquel Gomila/SOCIB

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Sunfish tagged with an X-Tag at Eastern Taiwan. Credits Tuna and Billfish Tagging Project in Taiwan

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11.09.2018 Animal tracking applications Unlocking the mysteries of the Arctic fox

The Argos satellite telemetry system made it possible for a team of researchers led by Dominique Berteaux from the University of Québec in Rimouski to better understand the behavior of the mysterious Arctic fox in Canada’s Nunavut region, as revealed in a recent article in Le Monde.

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21.08.2018 Birds tracking Lesser Kestrels back in Bulgaria

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An Argos-tagged juvenile whale shark swims through the waters of Panaon Island, Southern Leyte (Credits LAMAVE).

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Whale sharks are about the opposite of your archetypal shark. These gentle giants, the biggest fish in Earth’s oceans, are living on a steady diet of plankton (with the addition of small crustacean, fish and squids). There’s still a lot we don’t know about this wildlife marine species, though. Understanding…