In 1939 J.E Hamilton published his second report on Falklands’ southern sea lions. His reports are part of the Discovery Reports – the culmination of seminal multi-disciplinary research that involved a series of Antarctic cruises and land-based surveys between 1925 - 1951. Hamilton’s report contained a short note on the winter migration of southern sea lions. The note was based on his observations of the Cape Dolphin colony between 1935 – 1937. In summary, Hamilton suggested part of the Falkland Islands population may migrate away from the Islands during winter. His idea stuck. A quick internet search on southern sea lions reveals statements such as ‘the Falkland Islands are largely abandoned during the winter’, undoubtedly in reference to Hamilton’s salient work. However, while some females move to different haul out sites with their pups over winter and males disperse from breeding beaches, do sea lions really leave the Falklands entirely? A glance at Sealing on the Falkland Islands by local author J.R. Allen suggests that at least some sub-adult and adult males actually remain at the Falklands year round. A fact that I am sure many local land owners would also attest to.

The rain, sleet and snow held off just long enough for us to deploy satellite tags on four young males (60 - 120 kg) and two young females (60 kg). This is the first time juveniles have been tracked at the Falklands, so we follow their movements over winter with much anticipation! Maps of foraging routes to follow shortly.

Adult female southern sea lion equipped with a satellite tag in the Falkland Islands (Andrew Stanworth)

 - Males can be up to 3 times larger than females, making the Southern sea lion the most sexually dimorphic of all sea lion species (Steller, New Zealand, Australian, Californian and Galapagos sea lion)

- Adult males weigh 350 kg, while females 80 - 170kg and reach over 2 meters in length.

Southern sea lions are top predators in our marine environment. That means that just like seabirds, sea lions play an important role in maintaining the health of our seas. It may come as a surprise, but southern sea lions are one of the least studied pinniped (seals, sea lions, walruses) despite their wide distribution (Chile, Falkland Islands, Peru, Uruguay, Argentina). Information gathered on this enigmatic and iconic animal is therefore important locally and globally.

The slideshow consists of 34 images - a total of 5 Mb of stunning sea lion pictures...

If a picture is worth a thousand words - this is our largest sea lion article yet!