Drake Passage
24th March, the Drake Passage.
Weather-worn, exhausted and happy, we braced ourselves (and our stomachs) for our first day back in the Drake Passage. It’s safe to say we were all sad to leave one of the most beautiful and exhilarating locations we’d ever experienced, but that didn’t mean we weren’t going to soak up every last minute we had left on the water. We kicked it off with a breath taking sunrise, spouting fin whales, and soaring albatrosses, all while trying to balance through four-meter rollers.
Those who were not on deck scouring for marine life amongst the whitecaps and swell could be found enjoying lectures from the expedition team throughout the day. Our guide, Ali, told the story of the many women who left their mark in polar history, including Kathleen Scott and Emily Shackleton, illustrating the challenges they endured as well as the influence they exerted during the time of polar exploration both past and present. Our very own Sonja discussed Southern Ocean ecology and management, highlighting whaling and sealing history, krill fisheries, and damage caused by long line fisheries, such as seabird bycatch. This was further discussed later by our guide Christian in a lecture on seabird conservation. He focused on the vulnerability of albatross to long line fishing specifically, as they are long-lived, mate for life, and only produce a single chick every two years. He explained that the chick requires bi-parental care, so if one parent were to drown in a long line, for example, the chick would also die and the surviving parent would no longer breed after losing its mate. We all felt very fortunate to be able to see multiple species of these amazing birds on a daily basis during our trip! Lars gave a presentation on the use of elephant seals as oceanographers. He explained how SMRU tags could be attached to seals, who then go about their seal business, all the while collecting data on temperature, salinity, and depth, in environments that are otherwise inaccessible to us. He confirmed that the female elephant seal we saw hauled out the day before at Whaler’s Bay had a flipper tag attached, and was one of his study animals from 2008! Pretty cool! The excitement over scientist seals was briefly interrupted by a group of hourglass dolphins that passed right next to the boat, as all the guests flocked to the windows to catch a glimpse…. sorry Lars!
Later in the evening some of us students gave a presentation during our daily recap. We shared with guests the total numbers of seabirds and marine mammals sighted, where the animals were sighted along our ship’s track, and photos of the numerous species we identified. We discussed our survey protocols and also explained the information we gained about the environment from the use of our secchi disc, which describes the depth of the photic level, giving an indication of suspended material or primary productivity in the water. Additionally, we talked about our CTD, which gives conductivity (salinity) and temperature at different depths. The students then explained that the data we collected could be compared between multiple years, and we hope to examine any changes or patterns in the abundance and distribution of animals observed, potentially relative to a changing environment. Lainie highlighted the importance of tourist vessels as platforms of opportunity, which help scientists get to remote (and usually costly) locations.
As we wrapped up our talks and meetings for the day, we started to feel the increasing swell of the ever unpredictable Drake Passage. All we could hope for was to outrun the approaching storm as we continued our way north towards Ushuaia!
Caroline