Compiled seabird densities and distance to fronts in the Southern Ocean

We conducted a Southern Ocean seabird data synthesis using previously collected Antarctic-wide cruise data to determine seabird species assemblages and quantitative relationships to fronts as a way to provide context to the long-term Palmer Long Term Ecological Research (LTER) program and the winter Southern Ocean Global Oceans Ecosystems Dynamics (GLOBEC) studies in the eastern Bellingshausen Sea. We combined 9 cruises conducted in areas around the Antarctic continent during the summer (October-March) for an Antarctic-wide summer data set with 2348 transects and 63 species seen at least once. We combined seven cruises conducted in areas around the Antarctic continent during the winter (April-September) for an Antarctic-wide winter data set with 1591 transects and 56 species seen at least once. We used 6 Palmer LTER cruises which, combined, had 1446 transects and 29 species seen at least once. The 4 winter Southern Ocean GLOBEC cruises combined had 652 transects and 16 species seen at l..., The Southern Ocean GLOBEC cruises will be referred to as the Bellingshausen winter cruises and the Palmer LTER cruises as the Bellingshausen summer cruises.
Field and Analysis Methods
All cruises used strip transects to collect data on species occurring along the cruise track. In general, two observers carried out surveys from one side of the ship, usually from the flying bridge. Strip width was 300 m wide. On all cruises, observers noted time of sighting, species identity, whether the bird was stationary (e.g., standing on ice, sitting on water) or flying, and, if flying, direction of the flying bird in relation to the ship. Species sightings were made continuously on all but 3 cruises (winter Aurora Australis cruises) where 10-minute intervals were used. Survey effort was partitioned into 30-minute bins, sequentially, for surveys with continuous counts. All counts were adjusted for bird flux (movement of birds relative to that of the ship) using ship speed, wind speed and direction, a..., , # Compiled seabird densities and distance to fronts in the Southern Ocean

Cruise Data
We combined 9 cruises conducted in areas around the Antarctic continent during the summer (October-March) for an Antarctic-wide summer data set. The cruises were:
Northwind 1976 (Ross Sea)
Burton Island 1977 (Pacific sector of the Southern Ocean)
Northwind 1979 (Ross Sea)
Melville and Westwind 1983 (Weddell-Scotia Confluence)
Glacier 1979 (Ross Sea)
Polar Star 1987 (Bellingshausen Sea)
Polar Duke 1988 (Bellingshausen Sea)
N. B. Palmer 1994 (Amundsen and Bellingshausen Seas)
Aurora Australis 2000 (East Antarctica)

We combined seven cruises conducted in areas around the Antarctic continent during the winter (April-September) for an Antarctic-wide winter data set. These cruises were:
Polar Duke 1985 (Bellingshausen Sea)
Melville and Glacier 1986 (Weddell-Scotia Confluence)
Polar Duke 1987 (Bellingshausen Sea)
Polar Duke 1988 (Bellingshausen Sea)
Aurora Australis 1998 01 (East Antarctica)
Aurora Australi...,