Mass stranding of at least four Cuvier’s beaked whales (Ziphius cavirostris) was recorded in southeastern Crete. The four cetaceans stranded almost simultaneously on neighboring shores. Another whale was found stranded alive, and was guided back into the sea–its fate still remains unknown.
It is, however, highly likely that more beaked whales have died in the area, which may either never strand on the coast or never be detected. This is due to the prevailing northern and northwestern winds, which can carry the carcasses either further out to sea or onto more inaccessible parts of Crete’s coastline.
The simultaneous stranding of these rare cetaceans indicates anthropogenic causes. International experience has shown that various beaked whale species are particularly sensitive to specific frequencies of intense underwater noise pollution, which force them into an abrupt ascent from the deep waters where they feed. Such sudden ascent leads to embolism, which is usually fatal.
Since yesterday, the Archipelagos Institute of Marine Conservation, in collaboration with international environmental organizations, has launched a detailed investigation of the electronic tracks of vessels that traversed the waters south of Crete in recent days. Underwater noise of such intensity can be caused either by the use of antisubmarine sonars on naval ships or by seismic surveys. The evidence so far points to naval sonars as the most probable cause. Notably, naval vessels of various nationalities operate in this region, and although in peacetime their tracks should be visible, in most cases they are not.
Yesterday’s setback to the population of beaked whales in the Hellenic Trench is likely irreversible, as these whales are among the very few cetacean species that do not migrate but instead remain in the same marine area throughout their lives—typically in regions with deep oceanic trenches. This makes population recovery extremely difficult.
As in similar cases, the contributions of local veterinarians and community members, who volunteered their time and efforts during these tragic events, were especially vital and greatly appreciated. However, without specialized equipment on constant standby, the necessary expertise, and trained support teams, invoking any national stranding response network—capable of providing treatment or conducting proper necropsies—rings hollow in the face of such a grave and tragic incident.
Unfortunately, under the existing conditions, it was most likely not possible during the necropsies to collect the samples that could confirm whether the deaths were caused by embolism, since this requires full necropsies with emphasis on the detailed examination of the auditory system and the brains of all the dead beaked whales. We plan to return to this important issue in greater depth very soon.
For a country, a Mediterranean region, and Europe that proudly proclaims–through lavish conferences–their supposed commitment to protect the seas, it is unthinkable that we remain spectators to the decimation of the last remaining of this rare species still surviving in our waters. Nowhere in the Greek seas does there exist a truly efficient stranding response network for marine mammals.
