A tag followed the eel to his long-invisible appointment

For a long time, the tiny larvae were a major clue to locate the reproduction of the European eel in the Sargasso Sea. There was still a huge difficulty: following adults to this region of the Atlantic. In 2022, a study reported the results of beacons placed on twenty-six eels from rivers in the Azores.

These devices had to detach and transmit their information after being reassembled. Several final locations were in the Sargasso Sea; one reached the presumed breeding area. The data thus linked migrating eels to a region that larval observations had designated for about a century.

The mystery does not entirely disappear. The researchers did not film the spawning, and the departure to the Azores does not document the entire route from the continental European coasts. This distinction makes the discovery more precise: an essential stage of the journey became observable, while the rendezvous itself retained a part of its secret.