ECOSYSTEM SURVEY OF THE BARENTS SEA AUTUMN 2015

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1 9. MARINE MAMMALS AND SEABIRD MONITORING 9.1 Marine mammals Text by R. Klepikovskiy and N. Øien Figures by R. Klepikovskiy In total 2028 individuals of 11 identified species of marine mammals in August-October 2015 were observed (42 individuals in total was not identified). The results of observations are presented in Table and Fig As in previous years, the most often observed species was white-beaked dolphin (Lagenorhynchus albirostris) (some more than 60% of all registrations). This species has a wide distribution in research area. The most meetings of this dolphin closely capelin, herring, polar cod and other cod with different densities were recorded, and it was in western, central and eastern parts of the Barents Sea between 72º-78º N. The largest groups of these animals (25-35 individuals) in the western regions, and the New Land (Novaya Zemlya) Archipelago were recorded. Numbers of white-beaked dolphin meetings in comparison with was increased. Table Number of marine mammals individuals observed from the R/V Johan Hjort, Helmer Hansen, G.O. Sars, Vilnyus during the ecosystem survey in Order / suborder Cetacea/ Baleen whales Cetacea/ Toothed whales Pinnipedia Name of species Johan Helmer G.O.Sars Vilnyus Total % (english) Hjort Hansen Blue whale Fin whale Humpback whale Minke whale Sei whale Unidentified whale Sperm whale White-beaked dolphin Harbour porpoise Killer whale Unidentified dolphin Unidentified seal Bearded seal Walrus Total sum Besides white-beaked dolphin among toothed whales sperm whale (Physeter macrocephalus), harbour porpoise (Phocoena phocoena), and killer whale (Orcinus orca) were observed. Sperm whale met in the western part of research area at deep waters. For this species also far stopping at place as in previous years was recorded, animals far than 25º E was met. The harbor porpoise mainly in couples in the south-eastern regions to 73º30'N was observed. These animals on the herring, capelin and juvenile cod aggregations were recorded. Killer whale this year was met in the west part of research area is likely to herring and in the north-west of the Svalbard Archipelago and in the area of the Victoria Island - in the field of possible concentrations of pinnipeds.

2 Figure Distribution of toothed whales observed in August-October 2015 Figure Distribution of baleen whales observed in August-October 2015

3 Among baleen whales, the most observed were minke (Balaenoptera acutorostrata), humpback (Megaptera novaeangliae) and fin (Balaenoptera physalus) whales (with about 35% of all the animals). Minke whale in research area was widely distributed. The most dense concentrations of this species in area of the Hope Island and the Great Bank on capelin aggregations were recorded. In southern part of the Barents Sea minke whale on herring, juveniles capelin, cod, sand lance and other fish aggregations was met. Increasing numbers of humpback whale in comparison with was recorded this year. The most meetings of these animals in the area of the Hope Island, the Great Bank and the Franz Josef Land were recorded. Here, together with minke whale and fin whale as single individuals and groups are actively feeding on capelin humpback whales, numbering up to 110 individuals were recorded. Fin whale observations this survey was increased. The most observations this species closely the Svalbard Archipelago, the Bear Island, and the Great Bank were recorded. Here these animals with minke whale and humpback whale were fed. In areas northward of the Svalbard Archipelago blue whale traditionally was observed. The Norwegian observers recorded sei whale on the Great Bank who was not observed early. From pinnipeds during research period only walrus (Odobenus rosmarus) and bearded seal (Erignathus barbatus) were observed. This year the harp seal (Phoca groenlandica) summerautumn concentrations were not recorded. It was caused by this year poor ice condition in the Barents Sea. Ice edge far in the northern are was located. Walrus closely the West Spitsbergen Island, the White Island, and northward of the Svalbard Archipelago was recorded. Bearded seal northward of the Svalbard Archipelago was met. Also due to the remove of ice edge far to northern part of research area polar bears (Ursus maritimus) were not observed. 9.2 Seabird observations Text by P.Fauchald and R. Klepikovskiy Figures by P.Fauchald Seabird observations were carried out by standardized strip transect methodology. Birds were counted from the vessel s bridge while the ship was steaming at a constant speed of ca. 10 knots. All birds seen within an arc of 300 m from directly ahead to 90 to one side of the ship were counted. On the vessels Helmer Hansen, GO Sars and Johan Hjort, birds following the ship i.e. ship-followers, were counted as point observations within the sector every ten minutes. Shipfollowers included the most common gull species and Northern fulmar. The ship-followers are attracted to the ship from surrounding areas and individual birds are likely to be counted several times. The numbers of ship-followers are therefore probably grossly over-estimated. Total transect length covered by the Norwegian vessels (Helmer Hansen, GO Sars and Johan Hjort) was 5736 km. Total transect length covered by Vilnus was 5056 km. A total of birds belonging to 39 different species were counted (Table 9.2.1). The highest density of seabirds was found north of the polar front. These areas were dominated by Brünnich s guillemots (Uria lomvia), little auk (Alle alle), kittiwake (Rissa tridactyla) and Northern fulmar (Fulmarus glacialis) (Fig ). Broadly, the distribution of the different species was similar to the distribution in the 2014 survey (Fig ). Alcids were observed throughout the study area but the abundance and species distribution varied geographically. Little auks were found in the northern area, Brünnich s guillemots were found in the central and northern area, Atlantic puffins (Fratercula

4 arctica) were found in the western part and common guillemots (Uria aalge) were found in the south. Among the ship-followers, black-backed gulls (Larus marinus) and herring gull (Larus argentatus) were found in the south, close to the coast. Glaucous gull (Larus hyperboreus) was found in small numbers in the south-eastern area, kittiwakes were found in high density in the central and northern area, while Northern fulmars were encountered in highest numbers in the west and south. Figure Seabird observations in 2014 (top) and 2015 (bottom). Left panel; positions of transects, middle panel; distribution of auks, right panel; distribution of ship-followers (gulls and fulmar).

5 Table List of species encountered during the survey in Note that ship-followers were counted differently on the Norwegian and Russian vessels. English name Scientific name Norwegian vessels Russian vessel Razorbill Alca torda 4 0 Little Auk Alle alle Pink-footed goose Anser brachyrhynchus Meadow pipit Anthus pratensis 1 0 Ruddy turnstone Arenaria interpres 1 0 Purple sandpiper Calidris maritima 0 31 Black guillemot Cephus grylle 36 0 Puffin Fratercula arctica *Northern fulmar Fulmarus glacialis Yellow-billed loon Gavia adamsii 0 1 Black-throated loon Gavia arctica 0 6 Great northern loon Gavia immer 2 0 Red-throated loon Gavia stellata 2 0 *Herring gull Larus argentatus *Mew gull Larus canus 4 0 *Lesser black-backed gull Larus fuscus 8 0 *Heuglin's gull Larus heuglini 0 49 *Glaucous gull Larus hyperboreus *Great black-backed gull Larus marinus Sabine's gull Larus sabini 1 0 Northern gannet Morus bassanus 17 7 Northern wheatear Oenanthe oenanthe 1 0 Ivory gull Pagophila eburnea 21 0 Unident. Sparrow Passeridae spp. 1 0 European shag Phalacrocorax aristotelis 3 0 Great cormorant Phalacrocorax carbo 5 0 Snow bunting Plectrophenax nivalis 3 7 European goldenplover Pluvialis apricaria 5 0 Sooty shearwater Puffinus griseus 13 2 Goldcrest Regulus regulus 1 0 *Kittiwake Rissa tridactyla Common eider Somateria mollissima 4 0 King eider Somateria spectabilis 0 70 Long-tailed skua Stercorarius longicaudus 13 0 Arctic skua Stercorarius parasiticus Pomarine skua Stercorarius pomarinus Great skua Stercorarius skua 14 0 Unident. Skua Stercorarius spp Arctic tern Sterna paradisaea 39 2 Common guillemot Uria aalge Brünnich's guillemot Uria lomvia Unspec. guillemot Uria spp Total *Ship-followers