WESTERN GRAY WHALE ADVISORY PANEL 18Th Meeting WGWAP-18
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WESTERN GRAY WHALE ADVISORY PANEL WGWAP-18/INF.8 18th meeting 15-17 November 2017 PUBLIC WESTERN GRAY WHALE ADVISORY PANEL WGWAP-18/INF.8 18th meeting 15-17 November 2017 PUBLIC Cetacean surveys in the coastal waters of the Russian Pacific in 2014-2016 Olga A. Filatova1, Ivan D. Fedutin1, Olga V. Titova2, Olga V. Shpak3, Alexandr M. Burdin2, Erich Hoyt3 1 Department of Vertebrate Zoology, Faculty of Biology, Moscow State University, Moscow, Russia 2 Kamchatka Branch of Pacific Institute of Geography FED RAS, Petropavlovsk-Kamchatsky, Russia 3 Severtsov Institute of Ecology and Evolution RAS, Moscow, Russia 4 Whale and Dolphin Conservation, UK Knowledge on the distribution of cetaceans is very important for their conservation in terms of growing industrial activity on the sea shelf. Cetacean distribution in the coastal waters of the Russian Far East is poorly studied, because wide-area cetacean surveys are mostly conducted outside the coastal 12-mile zone. The numbers of some large whale species (humpback whale Megaptera novaeangliae, fin whale Balaenoptera physalus) increased in the last ten years due to the recovery after the ban of commercial whaling. The increase in abundance leads to the changes in their distribution in the waters of Far Eastern seas. We conducted surveys to estimate cetacean distribution in the coastal waters of the eastern Kamchatka peninsula, Commander and Kuril Islands, western and northern Okhotsk Sea. We worked from different platforms (ranging from 7.5m inflatable catamaran to 30m cargo ship); observations along the route were continuous during the light hours, weather permitting. When we encountered cetaceans, we recorded the GPS point, species, number of animals, bearing and distance to the animals. In case if we encountered humpback whales and some small whale species, we stopped the survey and launched an inflatable motor boat to approach the animals for photoidentification and biopsy sampling. Fin whales (and in some cases also humpbacks) were photographed from the ship/yacht. We identified individual whales using their natural markings observed on photographs. In this report we include only the encounters of large whales (all baleen whales and sperm whale), because other species are not under the jurisdiction of the International Whaling Commission. Eastern Kamchatka We surveyed the waters of eastern Kamchatka in 2015 onboard of 30m cargo ship and 10m yacht. In 2016, a short survey was conducted in Kronotsky Gulf. Besides, regular small-boat surveys were performed in Avacha Gulf as a part of killer whale research project. We found several large feeding aggregations of humpback whales in Karaginsky Gulf, and some solitary whales and pairs occurred in Ozernoy, Kamchatsky and Avacha Gulfs (Fig. 1). Encounters with fin whales were regular in Karaginsky, Ozernoy and Kamchatsky Gulfs. The highest concentration of large cetaceans was found in Karaginsky Gulf in the northern and southern parts of Litke Strait. There we observed the feeding aggregations of humpback whales and several pairs of fin whales. Also, the high concentration of humpback whales and fin whales was observed near Kronotsky Cape, but this aggregation was limited to a specific region near the Cape and did not extend to the adjacent areas. In the waters of Karaginsky Gulf we photo-identified 56 humpback whales (see Filatova et al. 2017 and Titova et al. in rev. for more details). Eight of them were matched with the catalog of animals encountered in the waters of the Commander Islands. Two humpback whales were identified in Ozernoy WESTERN GRAY WHALE ADVISORY PANEL WGWAP-18/INF.8 18th meeting 15-17 November 2017 PUBLIC Gulf, and three humpbacks – in Kamchatsky Gulf. Four humpbacks were identified in Kronotsky Gulf near Kozlova Cape, one of them was previously identified off Bering Island in 2013. Fin whales were always encountered in groups of two animals. In total, we have identified 11 individual fin whales. One pair was encountered three times: twice in Ozernoy Gulf on the 19th and the 20th of August and once in the southern Kamchatsky Gulf on the 4th of September. Gray whales (Eschrichtius robustus) were observed in their traditional feeding area – Olga Bay in the northern Karaginsky Gulf, as well as in other regions of Kronotsky Gulf and near Kronotsky Cape. In Avacha Gulf, humpback whales were common but not frequent. They also occurred south of the Gulf near Piratkov Cape and north of the Gulf near Shipunsky Cape. In 2016, a single right whale Eubalaena japonica was observed in Avacha Gulf (for more information on right whale encounters in the western North Pacific, see Ovsyanikova et al. 2015). Figure 1. Encounters with cetaceans in the Russian Pacific. Top-left – the whole study area, top-right – eastern Kamchatka, Commander Islands and GIzhiginskaya Gulf, bottom – Kuril Islands. Commander Islands In the Commander Islands, we worked from a land-based field camp using small boats that allowed us to survey the area about 115 km in length along the southwestern shore of Bering Island. Additionally, we performed opportunistic survey around the Islands onboard of 30m ship. The area is reach in cetaceans; the most common species of large whales is the humpback whale. Over the years, we have identified 1375 individuals in this area (see Filatova et al. 2017 and Titova et al. in rev. for more details). Minke whale (Balaenoptera acutorostrata) and sperm whale (Physeter macrocephalus) are less numerous but common. Fin whales, although common off Kamchatka coast, were not observed near the Commander Islands. WESTERN GRAY WHALE ADVISORY PANEL WGWAP-18/INF.8 18th meeting 15-17 November 2017 PUBLIC Kuril Islands The Kuril Islands is a 1000 m long island chain that border Kamchatka peninsula in the north and Japan in the south. In August 2014, we surveyed the northern Kuril Islands and southwestern Kamchatka on board of 10m yacht. In August 2016, we conducted a survey along the whole Kuril Island chain on board of the same yacht. Sperm whales occurred along all the chain of Kuril Islands, but were more frequent in the areas with steep underwater slopes. Besides sperm whales, we registered a small feeding aggregation of humpback whales off northern Kuril Islands and encountered two humpback whales off southern Kuril Islands. Only one fin wale was observed during this survey off Urup Island (southern Kuril Islands). In 2014, we observed two right whales in the northern Kuril Islands. Minke whales were common in the northern Kuril Islands but rare in other regions of the chain. Western Okhotsk Sea In the western Okhotsk Sea, we conducted a survey along the western coast of Sakhalinsky Bay, around the Shantar Islands and in adjacent mainland bays in 2015 using 7m catamaran. Besides minke whales, we encountered several bowhead whales both in the waters of the Shantar Islands and near the mainland coast. Minke whales were mostly encountered in open waters of the Shantar archipelago, and two whales were observed in the bays. Several bowhead whales (Balaena mysticetus) were encountered near the shoreline in Lindholm strait. Northern Okhotsk Sea We performed surveys using 15m boats in two areas of the northern Okhotsk Sea in 2016: in Gizhiginskaya and Tauiskaya Gulfs. The most common species of large whales was the minke whale. In Tayiskaya Gulf, it was the only large whale species observed. In Gizhiginskaya Gulf, we encountered two single juvenile bowhead whales and a gray whale female with a calf off the mouth of Gizhiga river. A pair of gray whales was encountered in the period close to the time of calf separation (usually in August) (Jones, Swartz 2002), and therefore this encounter away from the well-known summer feeding grounds is especially interesting. Comparison with the photo-catalog of gray whales summering near Piltun Lagoon on the east coast of Sakhalin Island revealed that this individual has not been observed there (O. Sychenko, pers. comm.). Genetic analysis revealed that the female had a rare haplotype of mitochondrial DNA that is found only in 6.8% of whales from the eastern population and have not been observed in whales from Sakhalin Island (d-loop – D, cytochrome b – 07). Given the numerous reports of gray whale sightings off the coast of Magadan region (Grachev A.I., unpubl., interviews with local residents) it is possible that there is a separate small feeding aggregation of gray whales in Gizhiginskaya Gulf. This work was supported by Pew Charitable Trusts and Russian Geographical Society. References Filatova O.A., Titova O.V., Fedutin I.D., Ovsyanikova E.N., Okabe H., Kobayashi N., Acebes J.M., Burdin A.M., Hoyt E. 2017. Photo-identification of humpback whales (Megaptera novaeangliae) in the Russian Pacific. Report to the Scientific Committee of the International Whaling Commission SC/A17/NP/02. WESTERN GRAY WHALE ADVISORY PANEL WGWAP-18/INF.8 18th meeting 15-17 November 2017 PUBLIC Jones M.L. and Swartz S.L. 2002. Gray Whale. In: Encyclopedia of marine mammals. Eds: W.F. Perrin, B. Wursig, J.G.M. Thewissen. Academic Press. Pp. 524-536 Ovsyanikova E.N., Fedutin I., Belonovich O.A., Burdin A.M., Burkanov V., Dolgova E., Filatova O., Fomin S.V., Hoyt E., Mamaev E., Richard G., Savenko O., Sekiguchi K., Shpak O., Sidorenko M., Titova O.V. 2015. Opportunistic sightings of the endangered North Pacific right whales (Eubalaena japonica) in Russian waters in 2003–2014. Marine Mammal Science. 31(4): 1559–1567. Titova O.V., Filatova O.A., Fedutin I.D., Ovsyanikova E.N., Okabe H., Kobayashi N., Acebes J. M., Burdin A.M., Hoyt E. (in rev.) Photo-identification matches of humpback whales (Megaptera novaeangliae) from feeding areas in Russian Far East Seas and breeding grounds in the North Pacific. Marine Mammal Science. .