Last “Atypical” beaked whales mass stranding in the Canary Islands (July, 2004)

Abstract

In July 2004, four Ziphius cavirostris stranded in the Canary Islands several days after an international naval exercises were conducted north of the Canary Islands. During the maneuvers high intensity mid-frequency sonar was used. Three of the animals were fully necropsied. Abundant fresh non-digestive aliment was found in all stomachs. Hemorrhages were a constant finding in several organs. Although “in vivo” gas embolism could not be established due to decomposition, systemic fat embolism was diagnosed in all three beaked whales. Epidemiological and pathological findings were highly consistent with an “atypical” beaked whale mass stranding that was temporally and spatially associated with sonar. This was the last atypical mass stranding in the Canary Islands once an antisonar moratorium was established around the islands, following the EU parliament recommendation and Spanish government resolution in 2004.