https://doi.org/10.82144/5d077d0d https://seamap.env.duke.edu/dataset/358 https://www.gbif.org/dataset/df2c00e9-93e3-4ffb-9a33-d1a8e692138c https://obis.org/dataset/78987543-213d-464c-9bb0-a1729a91a505 Ramunas Zydelis Duke University Primary contact zydelis@duke.edu OBIS-SEAMAP Marine Geospatial Ecology Lab, Duke University

A328 LSRC building Durham NC 27708 US

seamap-contact@duke.edu https://seamap.env.duke.edu OBIS-SEAMAP Marine Geospatial Ecology Lab, Duke University

A328 LSRC building Durham NC 27708 US

seamap-contact@duke.edu https://seamap.env.duke.edu distributor Ramunas Zydelis Duke University Primary contact zydelis@duke.edu owner 2025-07-31 eng Original provider: Institute of Ecology of Vilnius University Dataset credits: Gediminas Vaitkus, Institute of Ecology of Vilnius University Abstract: Seabirds transect surveys were conducted in Baltic Sea from 1992 to 1999. Standard seabird offshore sampling techniques assume that line transect of 300 m width is basically used for counting birds sitting on the water surface, whereas the 'snap-shot' method is used for the counting of flying birds at strongly fixed intervals of time.<br><br> Additional efforts were put into studies of the offshore seabird and waterfowl movements. We recorded flying birds along 1,000 m wide transect over the 'classic' 300 m transect used for calculations of seabird densities during 'snap-shots'. Occurrence GBIF Dataset Type Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_type.xml Observation GBIF Dataset Subtype Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_subtype.xml Marine Biology Visual sighting Vessels Sightings Seabirds transect surveys density distribution N/A This work is licensed under a Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0 License. https://seamap.env.duke.edu/dataset/358 Oceans,Baltic Sea 17.68533 24.36367 58.88333 54.83183 1992-10-18 1999-03-08 Scientific names are based on the Integrated Taxonomic Information System (ITIS). species Alauda arvensis Eurasian skylark species Alca torda Razorbill species Alle alle Dovekie genus Anas Dabbling ducks species Anas crecca Eurasian teal species Anas platyrhynchos Mallard genus Anser Bean geese species Apus apus Common swift species Ardea cinerea Gray heron species Aythya marila Greater scaup species Bucephala clangula Common goldeneye species Carduelis spinus Eurasian siskin species Cepphus grylle Black guillemot species Chlidonias niger Black tern species Chroicocephalus ridibundus Common black-headed gull species Circus aeruginosus Western marsh harrier species Clangula hyemalis Long-tailed duck species Coloeus monedula Western jackdaw species Columba palumbus Common wood pigeon species Corvus corone Carrion crow species Corvus frugilegus Rook genus Cygnus Swans species Cygnus columbianus Tundra swan species Cygnus cygnus Whooper swan species Cygnus olor Mute swan species Erithacus rubecula European robin species Fringilla coelebs Common chaffinch genus Gavia Loons species Gavia arctica Arctic loon species Gavia immer Common loon species Gavia stellata Red-throated loon species Grus grus Common crane species Hirundo rustica Barn swallow species Hydrocoloeus minutus Little gull genus Larus Gulls species Larus argentatus Herring gull species Larus canus Mew gull species Larus fuscus Lesser black-backed gull species Larus hyperboreus Glaucous gull species Larus marinus Great black-backed gull species Melanitta fusca Velvet scoter species Melanitta nigra Black scoter species Mergellus albellus Smew species Mergus merganser Common merganser species Mergus serrator Red-breasted merganser species Motacilla alba White wagtail species Parus major Great tit family Passeridae species Phalacrocorax carbo Great cormorant genus Phylloscopus Willow Warblers species Podiceps auritus Horned grebe species Podiceps cristatus Great crested grebe species Prunella modularis Dunnock species Regulus regulus Goldcrest species Rissa tridactyla Black-legged kittiwake species Somateria mollissima Common eider genus Stercorarius Jaegers species Stercorarius parasiticus Parasitic jaeger species Stercorarius pomarinus Pomarine jaeger species Sterna hirundo Common tern species Sterna paradisaea Arctic tern species Sternula albifrons Little tern species Sturnus vulgaris Common starling genus Tringa Redshanks species Troglodytes troglodytes Winter wren species Turdus merula Common blackbird species Uria aalge Common murre species Vanellus vanellus Northern lapwing The main purpose of our work was to investigate spatial structure and dynamics of the offshore seabird populations and to assess their status in specific conditions of the Baltic Sea marine ecosystem. The main tasks of our work were the following:<br> -Study species composition, abundance and spatial distribution of seabird populations in different seasons of the year, distinguish dominating species and the most important seabird concentration areas in the eastern Baltic; <br> -Study community structure of inter-specific assemblages and ecological adaptations of wintering seabird populations; <br> -Study the processes of spatial dynamics and trends of spatial structure in regional seabird populations within the gradient of winter climatic conditions; and <br> -Study offshore migratory routes and temporary concentration areas of seabirds in the Baltic Proper. notPlanned Ramunas Zydelis Duke University Primary contact zydelis@duke.edu NA NA NA Ramunas Zydelis owner NA zd_358 2025-07-31T14:13:53-04:00 dataset Zydelis, R. 2020. Baltic Seabirds Transect Surveys. Version 1.5.0. Dataset published in OBIS-SEAMAP. https://doi.org/10.82144/5d077d0d. OBIS-SEAMAP Dataset Page UTF-8 Interactive map https://seamap.env.duke.edu/dataset/358 FGDC Metadata UTF-8 XML https://seamap.env.duke.edu/dataset/358/fgdc EML Metadata UTF-8 XML https://seamap.env.duke.edu/dataset/358/eml OBIS-SEAMAP zd_358 zd_358 Vaitkus, G. 2001. Spatial dynamics of regional wintering populations of seabirds in the gradient of wintering climatic conditions. Acta Zoologica Lituanica: 11 (3): 273-279.