The apparently obligate symbiosis between the diazotroph Candidatus Atelocyanobacterium thalassa (UCYN-A) and its haptophyte host, Braarudosphaera bigelowii , has recently been found to fix dinitrogen (N 2 ) in polar waters at rates (per cell) comparable to those observed in the tropical/subtropical oligotrophic ocean basins. This study presents the novel observation that this symbiosis increased in abundance during a wind-dri...

Light and iron availability are intertwined in controlling Southern Ocean primary production because several photosynthetic proteins require iron. Changes in light and iron availability can also affect phytoplankton species composition, which impacts nutrient cycling, carbon drawdown, and food web structure. To investigate the interactive effects of light and iron on phytoplankton growth, photosynthesis, photoacclimation strat...

In areas where commercial fishing is prohibited, demographic metrics obtained from recreational fisheries and fishery‐independent methods can be integral to population ecology and management. For Australian bass Percalates novemaculeata (Steindachner) and Murray cod Maccullochella peelii peelii (Mitchell), two key finfish species native to the recreational‐only fresh waters of New South Wales (NSW), Australia, recreational fis...

To understand the controls on distributions of ice algal communities in spring and the role of ice algae in under‐ice bloom development through possible seeding, we sampled the ice and water column in the Chukchi and Beaufort Seas over spring and summer. Field observations showed that high springtime concentrations of bottom ice algal communities were released from the ice into the water column by summer. Furthermore, during o...

During the 2010–2011 ‘Impacts of Climate Change on the EcoSystems and Chemistry of the Arctic Pacific Environment’ project, we measured photosynthetic parameters in natural Arctic phytoplankton assemblages from the Chukchi and Beaufort seas. Water‐column samples were taken from the near surface (3.1 ± 0.9 m) and subsurface (28 ± 10.3 m) at ∼ 85 stations each year representing a wide range of ecological conditions, including un...