Record number of southern fulmars (Fulmarus glacialoides) off southern Australia

Southern fulmars (Fulmarus glacialoides) are Antarctic seabirds that travel and forage in large flocks, moving between areas with high concentrations of their preferred prey (krill and other plankton) at the ocean surface. These prey species are most abundant in cold water, so southern fulmars spend most of their time at high latitudes in the Southern Ocean. However, large numbers of individuals have recently been seen well north of this range, irrupting in Australian continental waters. On the 5th of June 2021, we observed 44 individual birds, off Eaglehawk Neck in Tasmania. This is the largest congregation of southern fulmars ever observed in Australia, well outstripping the ten birds that previously held the record (seen out of the same port). In the photograph, the individual in the foreground belonged to this congregation, and the rainbow in the background shows the front of the next low-pressure system on its way, possibly bringing more fulmars in its wake. Seabirds are well known to be highly mobile in response to inclement weather, so it seems to be no coincidence that this event occurred a week after two severe low-pressure systems moved across Tasmania from the Southern Ocean. The circumstances may be more complicated than this though, as there is no clear coupling between food availability, weather conditions, and seabird occurrence in an area. Could it be that strong winds blew these birds north, or were the birds following passive food sources being actively moved by the associated water currents? Perhaps the large numbers in the area are even unrelated to changing local conditions, and are instead normal for the time of year, only now being detected with increasing survey effort in recent years?