While eels are known to be sensitive to electromagnetic fields [17, 18, 19], our results provide the first evidence that they derive positional information from the Earth’s magnetic field. We show that juvenile European eels possess a magnetic map that allows them to modify their orientation to take advantage of consistent ocean circulation features along their marine migration route.

The otolith (ear stone or ear bone) is the most commonly used structure for determining the age of fish. Otoliths are calcium carbonate structures found inside the heads of bony fish; sharks and rays lack otoliths. Each fish has three pairs of otoliths, which vary in shape and size. Otoliths are part of the fish's inner ear, allowing fish to hear and sense vibrations in the water and providing a sense of balance so they may better navigate their surroundings.

Otoliths grow throughout a fish's life by accumulating material on the outer surface around a core.

This installation focuses on 'akikodiwan' (aka Chaudiere Falls) and the plight of the freshwater eels, whose population has declined by estimates of 98% worldwide due to human encroachment and other environmental distresses such as hydro-electric dams.
In an effort to collaborate with the eels who have inhabited kitche zibi (aka the Ottawa river) since time immemorial, I worked with an interspecies communicator to solicit the willingness of the eels to express how they would like to be depicted and what they wanted humans to remember about how their livelihood is directly in relation to our wellbeing. - Cheryl L'Hirondelle, 2022

This captivating ability is exceedingly rare in nature. Birds and fish can move collectively, while some bacteria can coordinate the waving of whiplike appendages (SN: 7/31/14; SN: 5/28/19; SN: 7/13/15). Vinegar eels, however, are capable of more. “This is a combination of two different kinds of synchronization,” says Anton Peshkov, a physicist at the University of Rochester in New York. “Motion and oscillation.”

The electric eel generates large electric currents by way of a highly specialized nervous system that has the capacity to synchronize the activity of disc-shaped, electricity-producing cells packed into a specialized electric organ. The nervous system does this through a command nucleus that decides when the electric organ will fire. When the command is given, a complex array of nerves makes sure that the thousands of cells activate at once, no matter how far they are from the command nucleus.

Telemetry is a well-established technique to study the migration routes and behavioural ecology of animals in the wild. Over the past two decades, telemetry and tagging technology have benefitted substantially from miniaturization and software development6,7. Acoustic, radio and passive-integrated-transponder (PIT) telemetry depend on detection stations and are used to track eels in freshwater systems8,9,10,11. However, because radio and PIT signals are attenuated in saline waters, acoustic telemetry arrays are preferentially used in estuarine and marine environments12,13,14,15.