Is there a useless techno solution, such as applying contact tracing for Covid and a commendable techno solution, for example, aimed at protecting vulnerable animals? In Greece, since 2019, researchers have launched the SAvEWhales project, aimed at saving whales from possible collisions with ships. This ambitious project with ethical tendencies takes root in Greece, and its plunge into the abyss is carried out more precisely at the level of the Hellenic Trench, a kind of underwater canyon 5 km deep, formed by the convergence of the Eurasian and African tectonic plates in the Eastern Mediterranean. . This area, stretching from the Ionian Sea south to Crete and on to the Rhodes Sea, is the most valuable regional habitat for the largest toothed whale: the sperm whale.
This marine animal has a peculiarity: during the hunt, it makes pulsating sounds, a kind of clicking or clucking. Thus, the researchers set up a network of three hydrophones suspended from surface buoys at a depth of about 100 m and at a distance of 1 to 2 km from each other, which pick up the sounds made by sperm whales. Once received, audio data from all buoys, along with other data, is combined to provide 3D detection and localization of vocalizing animals. The system is quite simple: a computer program is responsible for comparing the time it takes the sound to reach each hydrophone, which allows triangulation of the whale’s position. Even more impressive is that the system can detect whales at depths of up to 900m and less than 10km from buoys by calculating the time it takes for the “click” to bounce off the ocean surface.
“The development, deployment and operation of the SAvEWhales observatory over two three-month periods in the summer of 2020 and 2021 demonstrated the ability to monitor in real time vocalizing sperm whales while feeding.the researchers explain. This could be an important tool to mitigate the effects of ship collisions, which pose the greatest threat to sperm whales in the eastern Mediterranean, especially when the main shipping lanes cross the Greek Trench and cannot be separated from sperm whale habitats by simple movement.”.
Since the period between the last “click” during a foraging dive and the whale’s resurfacing is typically 6 to 11 minutes, real-time positioning – with an accuracy of 30 to 40 meters – leaves enough time for evasive maneuvers, experts say. . But the system is not perfect. For example, individual whales are difficult to distinguish from a group of moving whales, and equipment can be damaged by weather and salt. The researchers have so far only conducted a pilot test and have so far faced the silence of the authorities on the placement of such lighthouses off the coast of Crete. I must say that this is an area used for oil production.