Turtles, seals, sharks, whales and penguins swim in puzzling circles, which may indicate a connection to the earth’s geomagnetic field.
Tomoko Narazaki of the Institute of Oceanography at the University of Tokyo is studying how green sea turtles move and found something incredible: They often swim in circles for no reason, as if they were mechanical movements.
Narazaki and his colleagues found the same behavior in animals such as sharks, seals, penguins, whales, and of course turtles. They all made unexpected circles at some point during their displacement.
From there, they decided to use sophisticated tracking technology to observe the animal’s movement, which allows the animal to be positioned in the three dimensions of its movement, taking into account all external factors throughout the journey and the force of the geomagnetic field. Earth.They published their findings in science.
Collecting high-resolution information about the movements of 3D marine animals allows them to observe their movements in a circle and discover different reasons behind strange movements.
Once, they observed a male tiger shark hovering, leaving a deep impression on the female. On another occasion, they recorded a relaxing spiral dive of a resting walrus, described in the studio as “falling like a fallen leaf.”
Some circling movements are related to foraging activities because they occur in known foraging areas.
Scientists have previously documented many marine hunting strategies involving circle swimming, such as the “bubble net” method used by humpback whales.
But they have observed many animals circling outside the foraging grounds or circling during the day or night without knowing that certain species are actively hunting.
Swim in a circle like a submarine
Although some of these observations remain a mystery, Narazaki and his colleagues suggested that many animals can swim in circles to collect navigational information.
The research team speculates that these motion patterns may even represent an intuitive connection with the earth’s geomagnetic field.
“Animals can walk around in circles to obtain direction/position signals from the geomagnetic field, especially when it poses a challenge to navigation”
The researchers pointed out in the study: “Interestingly, when conducting geomagnetic observations, the submarine will also move around in circles, because the omni-directional measured value can be used to offset noise such as the magnetization of the hull, so as to achieve accurate measurement. ”
They added: “Animals can move around in circles to obtain direction/position signals from the geomagnetic field, especially when it poses a challenge to navigation.”
Of course, the research team can also make these animals hover for a variety of known and unknown reasons at the same time. This may be a foraging strategy, and at the same time, they will collect geomagnetic information from the earth’s magnetic field.
To better understand hovering behavior—perhaps discovering new aspects of marine animal habits—Narazaki and his colleagues hope to combine some short-term data collected by the brand with long-term satellite tracking. The investigation continues. We will continue to inform.