Detecting Whales in Real Time To Reduce the Risk of Collisions
Where shipping routes cannot be moved, early detection becomes essential. SAvE Whales is being deployed as a permanent, real-time whale warning system for the Hellenic Trench, Greece. It is a complementary tool to existing protection measures such as re routing and speed reductions.
Sperm whales produce distinctive clicking sounds during every dive. SAvE Whales uses underwater hydrophones, moored on the seafloor, to detect these clicks and assess the animals’ position in real time. This passive acoustic monitoring is the only discreet and non-invasive method for detecting whales.
The acoustic recordings are preprocessed to detect and analyse the clicks before being transmitted to the analysis centre, where data from all deployed hydrophone stations are combined to confirm detections and determine the location of one or more whales.
The buoys are solar-powered and fully autonomous, communicating continuously with the analysis center via the mobile network. Crucially, access to the system is carefully controlled. Upon confirmed detection, ships will be notified to limit their speed to 10 knots, when transiting through the designated area of the Strait of Kythira. This will enable ships to adjust their speeds in a timely and safely manner and reduce the risk of collision with the endangered sperm whales.
Deployment in the Strait of Kythira
The initial deployment of SAvE Whales is planned for the Strait of Kythira, where shipping routes cannot be relocated. To cover the full high-risk area, two to three groups of acoustic stations will eventually be required. As a first step, two systems are currently deployed and tested to cover the western and eastern parts of the area enabling accurate acoustic detection in the starit of Kithyra.Upon detection ships will be warned in real time to reduce their speed to 10 knots. In March 2026, an addendum to the Memorandum of Understanding was signed to secure the participation of the Greek environmental fund Green Fund in the project’s implementation. The next steps include an international open tender for the SAvE Whales system to be launched by NECCA in 2026, followed by Site Acceptance Testing of the purchased equipment in 2027 and of the complete system in 2028, ahead of the full handover to the Greek Agency for Environment and Climate Change (NECCA).
SAvE Whales is designed as a blueprint: the technology can be adapted for other heavily trafficked sea areas where whale habitats and shipping routes overlap and routes cannot be moved.
