Understanding how a marine species uses the features of its environment is important for conservation. The northern elephant seals are close cousins to their southern equivalents. A number of tracking data exists, enabling to study their behaviors in comparison with ocean eddies and other environment data from remote sensing.
The northern elephant seal (Mirounga angustirostris) is found in the East of the North Pacific Ocean. They eat small fish and squid which are not possible to monitor permanently. The species was nearly extinct around late 19th century/early 20th century, but has recovered thanks to protection. However, a better understanding of how they are using the features of their environment will help in continuing protecting them. Ocean mesoscale eddies, in particular, are nutrient-rich, and a number of predator behaviors could be related to those features.
Tracking of northern elephant seals and eddies
A record of tracking data by Argos, and continuous in situ temperature measurements with also dive records, from 221 adult female northern elephant seals collected between 2004 and 2019 was used. The tracked seals were instrumented mostly at Año Nuevo State Park, California, USA (37.11°N, −122.33°W, individuals) and for a few at Islas San Benito, Mexico (28.30°N, −115.37°W; 20 individuals).
Elephant seal tracks (lines) and locations of eddy encounters (blue circles and orange squares). (from [Keates et al., 2022]
Eddies are used, but may not be actively looked for by northern elephant seals
Except for one individual which spent 30% of its time within and around eddies, most of the tracked seals spent little time in the detected eddies (however, the encounters kept for the analysis were only the ones detected with a high degree of certitude, which may have underestimated the time spent). However, when the elephant seals encountered an eddy, they spent more time across the edge (for both cyclonic and anticyclonic) or within (only for anticyclonic eddies). They were detected more in relation with anticyclonic eddies than cyclonic ones. The variability of behaviors seemed large between individuals, too, which show that an even larger number of tracking should be used in such studies.
Theresa R. Keates, Elliott L. Hazen, Rachel R. Holser, Jerome Fiechter, Steven J. Bograd, Patrick W. Robinson, Juan Pablo Gallo-Reynoso, Daniel P. Costa, 2022: Foraging behavior of a mesopelagic predator, the northern elephant seal, in northeastern Pacific eddies, Deep Sea Research Part I: Oceanographic Research Papers, Volume 189, Nov. 2022, 103866, https://doi.org/10.1016/j.dsr.2022.103866.
Understanding how a marine species uses the features of its environment is important for conservation. The northern elephant seals are close cousins to their southern equivalents. A number of tracking data exists, enabling to study their behaviors in comparison with ocean eddies and other environment data from remote…
Last year we met with Charles Drieu La Rochelle, member of the user support team in France, to find out more about CLS Group’s excellent customer care. But, did you know that he’s part of a dynamic duo? We thought it was time to introduce the other…
02.01.2023 Animal tracking applications Selecting sites for Harpy Eagles’ releases
Harpy Eagles are threatened birds of prey of Central and South Americas. A study show why and how releases of rehabilitated or captive-born animals should consider home range characteristics and habitat preferences. The Harpy Eagle (Harpia harpyja), found in tropical lowland evergreen forest from south…
20.12.2022 Animal tracking applications Loggerhead turtles and Mediterranean Marine Protected Areas
Assessing whether an endangered species visits the protected areas – or not – is an important indicator of their relevance. Tracking of loggerhead turtles in the Mediterranean Sea show that modifying and adding protected area would be necessary for their conservation. Main photo: Nesting female tagged by night…
28.11.2022 Animal tracking applications Common Woodpigeons keep their breeding sites, change their wintering ones
Tracking animals help in understanding their behaviour, which can benefit to their protection, even for abundant species such as the common woodpigeons. Their behavioral plasticity, demonstrated by such study should help them in maintaining their population. The common woodpigeon (Columba palumbus) is a very abundant and…
Beluga whales are Arctic cetacean very sensitive to noises, including underwater ship noises. For a long time, scarcity of such ships in the region meant it wasn’t a concern. With ice-free routes opening for longer period with global climate change, the question now arises. As…
20.10.2022 Animal tracking applications Do Juvenile Smooth Hammerhead sharks have a nursery in the Azores?
Smooth hammerhead sharks are a threatened species of shark – as most shark species. Locating their essential habitats, like the nurseries could make a difference in their protection. Argos can help by tracking juveniles. Sharks are among the most threatened marine species, as they are…
28.09.2022 Animal tracking applications A new tag to record diving behavior of large whales
A new tag dedicated to large whale has been developped and tested. It enables to record dive behaviors, using a software detection event to better summarize and compress the data to be used during long-range travels over several months. As we saw in a previous…
26.09.2022 Animal tracking applications Lost shark tag found thanks to the Animal Telemetry Network and the Argos goniometer
Marcus Drymon, Assistant Extension Professor at Mississippi State University Marine Fisheries Specialist and Dr. Greg Skomal, an accomplished marine biologist who we interviewed for Shark Week, were recently able to recover a lost shark tag thanks to NOAA’s Animal Telemetry Network (ATN) and an Argos goniometer loaned…
23.09.2022 Animal tracking applications Breaking news: Engineers and scientists collaborate to develop the first open-source Argos ear tag
For over a decade, researchers have been working on improving radio telemetry devices for polar bears. In 2018, the U.S. Fish and Wildlife Service, the World Wildlife Fund, IDEO, and MistyWest teamed up to develop a new Argos-based polar bear ear tag. After two years of…
21.09.2022 Argos news & events Argos metamorphosis update: not one but two Argos-4 instruments to be launched in the coming weeks!
We are just few weeks away from the planned launches of two Argos-4 payloads, an advanced satellite instrument that will track the movement of wildlife, as well as critical environmental data around the world. Argos-4 will ensure the continuity of the Argos-2 & Argos-3 missions while…
12.09.2022 Animal tracking applications Hudsonian godwits cross the windy ocean
The Hudsonian godwit is a migratory bird travelling a marathon, transoceanic flight from South America to Arctic or sub-Arctic North America. Their flight paths tracked using Argos, in relation with variable winds, can help understand how they travel such long distances. Photo: a Hudsonian godwit equipped with an…
01.09.2022 Argos news & events Dog recovers lost Argos tag from a Leafscale Gulper Shark
At the end of March 2022, Cristina Rodríguez-Cabello researcher of the Spanish Institute of Oceanography (IEO) in Santander (Spain), was working at her Centre when she received an unexpected yet exciting call from France. One of the archival tags she had attached to a deep-water shark…
31.08.2022 Animal tracking applications Lake charr ecotypes’ habitats differ
Lake charrs are freshwater fish found in the Laurentian Great Lakes (North America), among others. They nearly disappeared, but restoration was successful at least in Lake Superior. Understanding the different habitats of the lake charr ecotypes can help in restoring them in all of the Great Lakes. Photo:…
17.08.2022 Birds tracking Philippine eagles forage in human fragmented forests
Protecting critically endangered species aims to better assess where and when the main threats to these species occurs. Using satellite telemetry technology, Philippine eagles were tracked to define their home range and habitat use across their tropical forest breeding grounds and within human-occupied areas. Main Photo: A Philippine…
01.08.2022 Birds tracking Identifying reddish egrets stopover sites to protect their migrations
Migratory birds, especially those which depend on coastal wetland habitats, are among the threatened animals. Identifying the key sites in their life cycle, including the stopovers used during migration, is important for conservation efforts. Argos satellite telemetry can help by providing locations along the migrations and measuring residency…
26.07.2022 Argos news & events Shark week: Dr. Gregory Skomal talks tagging and what the future constellation will bring
“I think anyone who’s used Argos will have to admit that they’ve learned something revelatory. The more we use Argos to track animal movements, the more we see that their movements are far more complex and of greater scale than we ever imagined.” Featured photo credit:…
Loggerhead turtles can forage either on continental shelf or in the open ocean. The North Pacific population, nesting whole in Japan show both behaviours. Their foraging areas are pinpointing using isotopic analysis and Argos tracking, to better define conservation measures. Photo: a loggerhead turtle with an Argos PTT…
05.07.2022 Animal tracking applications A nursery for juvenile reef manta rays
Reef manta rays are a vulnerable species. They grow up in protected shallow areas such as lagoons. Tracking them with Argos can help to confirm that a given lagoon is a nursery for this species Photo: a female juvenile reef manta ray sized 220 cm (wingspan; they…
20.06.2022 Animal tracking applications Juvenile grey-headed albatrosses learn to decode their environment
Uncovering how young animals learn to move efficiently and find food, is one of the many possible uses of satellite telemetry. Here, researchers from British Antarctic Survey satellite-tracked juvenile grey-headed albatrosses to understand the effect of environmental conditions during this critical early stage of development. Photo: a…
13.06.2022 Marine animals tracking Harp seal juveniles learn on their own
Harp seal juveniles leave their native ice pack to forage and migrate on their own. Tracking them and recording their dive can help understand how they manage their first year. Ultimately, the question is their plasticity with respect to environmental changes. Photo: a juvenile harp seal with…
09.06.2022 Argos news & events How can CLS support your daily operations with Argos?
This month we’ve decided to take you back stage to meet Charles Drieu La Rochelle, member of the user support team in France, to find out more about CLS Group’s excellent customer care. What are the most frequently asked questions? When is the team available? Charles tells us…
31.05.2022 Argos news & events Argos metamorphosis update: Full-scale testing of Kinéis’ 25 nanosats has begun!
Ever wondered how small tags like the one on this cuckoo can communicate with satellites that are up to 650 km away? It all comes down to the highly sensitive receivers that make the Argos system so unique. The slightest radiofrequency interference between the different instruments…
25.05.2022 Birds tracking How do Egyptian geese find their way?
One of the mysteries of migrant animals is their ability to find their way back and forth during their long-range travels. Several hypothesis were tested on Egyptian geese to try to understand their navigation capacity. It seems they learn their way around. Photo: an Egyptian goose with…
10.05.2022 Marine animals tracking How many Mediterranean migrating eels are eaten on their way to the Atlantic?
Analysis of migrating eels’ tracks can provide with estimate of the rate of predation on them. It seems that half of the migrating silver eels released on the French Mediterranean coast can be consumed by marine mammals before reaching the Gibraltar Straight. Assessing such natural threats to an…
20.04.2022 Terrestrial mammals tracking Are the Arctic hares migrating?
A number of animals are migratory. The hares do not leap to mind when listing migrating animals. However, satellite telemetry confirms arctic hares very probably migrate in Northern Canadian Arctic. A lot of questions have still to be answered on these potential migrations. Photo: An arctic…
14.04.2022 Marine animals tracking Turtles in the Bay of Biscay
Juvenile sea turtles are cared and rehabilitated at Aquarium La Rochelle, in France. Since 2008, a few of them were equipped with Argos PTTs before being released. Analysis of their tracks could help understand if they were trapped in a nutrient-rich but cold in winter Bay of Biscay,…
31.03.2022 Birds tracking Red Kites wintering in Spain
Red kites are medium-sized partially migratory raptor. They often winter in Spain, but their behaviour there and during those non-breeding periods have not been extensively studied using satellite telemetry. A team used PTTs to understand better this season for those raptors, and consider what will become of them…
14.03.2022 Birds tracking A new king penguin colony in Magellan Strait?
King penguins are living around Antarctica, breeding on some of the sub-Antarctic islands. A new colony seems to have been established in Magellan strait, showing the high plasticity of the species. Argos enables to better understand the new colony behaviour. Photo: four study king penguins in different positions…
02.03.2022 Marine animals tracking Identifying whale migration routes in the global oceans
WWF has just published a report using 30 years of tracking for a meta-analysis of whale migration routes over all the oceans. This map of “migration highways” should help in protecting whales in general, but also the whole oceanic ecosystem, since they are a key species in its…