Cuvier’s Beaked Whale Mass Stranding Event Preliminary Report : simplebooklet.com

Cuvier’s Beaked Whale Mass Stranding Event - Preliminary Report 2 PRELIMINARY REPORT ON CUVIER’S BEAKED WHALE DEATHS IN CYPRUS On February 9-13, 2023, a total of 12 beaked whales were stranded, seven in southern and five in northern part of Cyprus. Most were dead when they were found, but some were alive, however, despite all efforts, none of the stranded whales survived. According to the preliminary results of the gross necropsy made on 5 whales on the north, it is assumed that they had died due to gas embolism caused by acoustic trauma. Beaked whales are known to be affected by sonars of naval exercises and seismic surveys all over the world. According to NAVTEX data, there were planned navy exercises with firing across large areas in the eastern, southern and western parts of the island on the days when whales stranded. All countries should cease their planned/unplanned naval exercises in the eastern Mediterranean, as there are concerns about the increase in stranding events.

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Cuvier’s Beaked Whale Mass Stranding Event - Preliminary Report 3 A total of 12 Cuvier’s beaked whales (Ziphius cavirostris) washed up on the west-northwest of Cyprus Island, one in Poli, one in Galia, three in Pomos, one in Pachyammos, one in Pirgos in the south and one in Gemikonağı, two in Gaziveren, one in Yeşilırmak and one in Erenköy in the north. Taşkent Nature Park (Cyprus Wildlife Research Institute – CWRI), the authorized institution for stranded whales in the north, intervened and carried out rescue efforts with the support of the Coast Guard, Lefke Municipality, Güzelyurt/Morphou Municipality, Security Forces Command, Police, fishermen in the region and volunteer citizens. Unfortunately, despite all efforts, stranded whales were either found dead or died shortly after stranding. Similar rescue efforts also failed in south, and all 7 whales stranded have also lost their lives.

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Cuvier’s Beaked Whale Mass Stranding Event - Preliminary Report 4 While 4 whales were transported to CWRI for necropsy studies, the necropsy of the whale in Erenköy was carried out on site. In addition to the CWRI, the necropsies were carried out together with representatives from the Veterinary Department, the Environmental Protection Department, the Animal Husbandry Department, and marine mammal experts from Turkish Marine Research Foundation (TUDAV).

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Cuvier’s Beaked Whale Mass Stranding Event - Preliminary Report 5 According to the preliminary results of the necropsy studies; Five young (2 female, 3 male) whales, ranging in length from 3.9 to 4.7 meters, were in good body condition except the one found in Erenköy. During the necropsy of all 5 animals, gas bubbles were clearly seen in the veins in various organs of all of them. Cestodes, nematodes and ascarid parasites were found in amounts that would not normally cause any ill effect from the gastrointestinal tract and all were collected for further investigations. In the individual in Erenköy, nematode infestation which covered the renal pelvis in the kidneys was observed intensely, which also spread to the ureter. All parasites were removed and stored appropriately for morphological and genetic studies.

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Cuvier’s Beaked Whale Mass Stranding Event - Preliminary Report 6 Especially in the liver, structural changes that may be related to gas embolism were observed and samples were taken for further analyses and the results of all examinations will be reported separately. According to the preliminary findings, a general hemorrhagic appearance was dominant in the organs, similarly in all five individuals. The gas bubbles in the veins, the changes in the organs and the pathologies indicated that gas embolism occurred due to the change in the normal diving behavior during the escape from the sound source, as in the decompression sickness. Bleeding around the head and ear canal are evidently implies that acoustic trauma is the reason for this. All of the 5 individuals were found to have full stomachs, which proves that deaths were caused by an acute event and not due to chronic effect or starvation.

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Cuvier’s Beaked Whale Mass Stranding Event - Preliminary Report 7 Apart from all these, a 20×16 cm plastic package was found in the stomach contents of an individual. Although it has been evaluated that this plastic package is not directly related to the death of the animal, it is an important example in terms of the damage that single-use plastic wastes can have on animals in our seas. Contrary to what was previously reported in the media, these cases are not related to the major earthquakes that recently took place in Türkiye. Although it is known that earthquakes have an acoustic effect, in this particular case a connection cannot be made as these earthquakes happened on land and the time between the earthquakes and strandings were 3.5 days apart. In addition to this, there is no proof of earthquakes causing death of whales anywhere in the World. Cuvier’s beaked whales are toothed whales and one of the 12 species of cetaceans found in Mediterranean, where they have a genetically separate population from the Atlantic ones. They usually feed on squids, are deep divers (usually 500-1500m), and prefer underwater canyons and complex seabed structures, however, they can also be found in abyssal plains. The Mediterranean population is estimated to be around 6000 individuals and is classified as Vulnerable (VU) on the International Union for Conservation of Nature (IUCN) Red List. Beaked whales are born around 3m and reach sexual maturity at the age of 7-11 years, at 5.5-6.0m in length. There is evidence from mass stranding events around the world in the past that beaked whales experience acoustic trauma caused by low and medium frequency sonars used in naval exercises and in seismic surveys for oil/natural gas exploration. Apart from this, illegal fishing with drift nets and ingestion of macroplastics are other threats for these animals in the Mediterranean. There have been about 20 known cases of mass stranding events in the Mediterranean since 1963, the most recent one on the Greek island of Corfu in February last year and associated with

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Cuvier’s Beaked Whale Mass Stranding Event - Preliminary Report 8 the seismic survey in the region. The Parties of the Agreement on the Conservation of Cetaceans of the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS) decided in 2013 that they must abstain from conducting naval exercises using sonar or underwater explosions around the "Areas of Special Concern for Beaked Whales" (Resolution 5.13). Also, it was learned that on Wednesday, February 15, 2023, a beaked whale, approximately 4 meters in length, washed ashore alive and was rescued back to the sea on the coast of Okurcular District of Antalya, Alanya, Turkey. According to the NAVTEX data obtained, it is known that the Russian Federation has planned navy exercises with firing in large areas in the eastern, southern and western regions of the island in February 2023. As a precautionary approach, and due to the fear of an increase in death toll, all countries should stop all planned/unplanned naval exercises in the eastern Mediterranean and especially in the Finike Seamounts (Anaximander) Special Environmental Protection Area, a unique marine ecosystem that supports fragile habitats and vulnerable fauna and flora species.

Cuvier’s Beaked Whale Mass Stranding Event Preliminary Report