Wildlife

New Whale Stranding Is Painful Evidence for Naval Sonar Risks

On April 1, while the U.S. and other navies played war games somewhere offshore, Cuvier's beaked whales began stranding along the southern coast of Crete. Those on the scene knew right away what they were dealing with, for the strandings were only the most recent in a line of similar calamities in the region, going back two decades. And in this case, as in the previous ones, all signs pointed to the U.S. Navy and its allies.

Cuvier's beaked whales are a remarkable species. They have the deepest recorded dives of all marine mammals, some descending an astonishing 9,500 feet (3,000 meters) below the water's surface before coming up for air. Favoring deep water, they don't strand nearly as often as coastal species, and they don't strand in large numbers, and they don't strand New Whale Stranding Is Painful Evidence for Naval Sonar Risksalive.

Yet, that is exactly what happened on April 1. Beginning around noon, three Cuvier's beaked whales came ashore in one spot along the Cretan coast, two others beached some 10.5 miles (17 kilometers) further west, and two more turned up another mile or two from there. All were alive when they stranded; rescuers managed to return most to the water, but, based on past experience, biologists in the region fear that they stranded again or perished at sea.

For the last week, the U.S., Greek and Israeli navies have been running a joint military exercise off Crete known as Operation Noble Dina. The exercise includes anti-submarine warfare training, which requires the use of high-powered military sonar.

Each of these events is tragic in its way, but this one feels particularly cruel. Just last year, the Scientific Committee of the Agreement for the Conservation of Cetaceans in the Black and Mediterranean Seas (ACCOBAMS), drew a map where sonar training should be avoided. One area on the map is off southeastern Crete — exactly where the new mass stranding occurred — around a highly sensitive marine area known as the Hellenic trench. But Greece fought the recommendation, and it wasn't adopted.

Now experts are despairing that, with stranding after stranding, the region's beaked whale populations are being decimated.

Beaked whales that have died from sonar exposure — at least the ones recovered in time for investigation — have suffered from a suite of severe, telltale pathologies, similar to those seen in decompression sickness, or the bends. Sonar is believed to kill them by disrupting their dive patterns. The ones that reach shore are considered the tip of an iceberg.