22 January, 2020
BAS biologist Dr Jennifer Jackson shares updates from the South Georgia southern right whale expedition currently in progress in the sub-Antarctic.
During January 2020, the British Antarctic Survey’s wild water whales team have been conducting surveys for southern right whales all around the sub-Antarctic island of South Georgia. The expedition is composed of ten international experts from five countries (the UK, USA, Canada, Brazil and New Zealand) and includes marine mammal observers, photo-ID specialists, geneticists, acousticians, a drone pilot and an expert in satellite tagging. The wild water whales expedition is running for 33 days on New Zealand research vessel the R/V Braveheart.
Since arriving in South Georgia on the 10th January 2020, the whale team have surveyed all around the island, between the coastal waters and the 500m shelf break far out to sea, using acoustics to listen for whales as well as an observer team to look for them.
The BAS wild water whales team have now been at sea for just over two weeks. They have sailed right around the island of South Georgia, seen countless humpback whales and regularly sighted Antarctic blue whales. Since they sighted their first southern right whale last week, they have seen right whales on four occasions, each time solo whales.
Why are there so few south right whales at South Georgia this season? We think it may be because they have decided to feed elsewhere this summer. Colleagues at the #trackingwhales research project in Argentina tagged 23 whales during the austral winter (in September 2019) in order to see where they went. Of those 23 whales, none have travelled to South Georgia this season, and as of the 20th January most are still on the Patagonian Shelf, presumably they are finding abundant food and so are delaying their migration south.
The wild water whales team have collected photo-ID from the right and blue whales they have encountered, and have also obtained small skin samples where possible, using a biopsy dart. These samples will be used by project Co-Investigator Dr Emma Carroll at the University of Auckland to identify and sex each whale via its unique genetic fingerprint. BAS collaborator Dr Gabi Stowasser will measure the skin chemistry of each sample and comparing this with the chemical profiles of zooplankton collected from the region, to identify what each whale is feeding on.
Excitingly, the team were also able to collect the first whale blow samples from a right whale over the weekend, as well as from a blue whale. These samples will be used by the expedition collaborators at Woods Hole to investigate the health condition of the whales by looking at their microbiome. To collect these samples, the team mounted a petrie dish on a drone and flew it over the whale. They also tried using a petrie dish on the end of a long pole when the whale was particularly close to the vessel.
The team have also used active acoustics (an echosounder) to map the prey field around the right whales on two occasions, to find out what kind of prey swarms they are feeding on. Southern right whales are thought to feed on Antarctic krill in South Georgia waters, but these waters also contain other types of zooplankton including copepods, which could be another important food source for right whales. Understanding what the whales feed on will help us better understand how they use South Georgia waters and where the most important feeding areas are for right whales.
Despite the scarcity of right whales this season, the team are in good spirits and have managed to do a very comprehensive sighting survey of the shelf waters of South Georgia, which will be useful for estimating the densities of different whale species using this region. As well as humpbacks, blue whales and right whales, they have also seen killer whales and fin whales on their surveys.
Led by British Antarctic Survey, the team includes scientists from the University of Washington, Oregon State University, NOAA, the University of Rio Grande do Norte, the University of Cambridge, and the Scottish Association of Marine Sciences. Other collaborators involved in the project include the University of Auckland (conducting the genetic work), Instituto Aqualie (collaborating on whale tracking), Woods Hole Oceanographic Institute (studying whale health), the Sea Mammal Research Unit (acoustic analysis and health), the University of Barcelona (analysing the historical catch record) and Happywhale, a citizen science based initiative who publish and share photo-identifications of whales online.
This voyage has been funded by the DARWIN PLUS initiative with the objective to estimate the population recovery of southern right whales at South Georgia, following 350 years of exploitation in the Southwest Atlantic. We are also very grateful for funding support from the South Georgia Heritage Trust and Friends of South Georgia island, and from EU BEST, as well as logistical support from the Government of South Georgia and the South Sandwich Islands.
We are dedicating this multi-disciplinary voyage to the memory of our colleague Dr Peter Best, a Cape Town based marine biologist who was one of the world’s foremost authorities on whales and dolphins of the Southern African region. The South Georgia project focuses on collaborative research to understand right whale recovery and foraging ecology, areas that Peter contributed enormously to during his career. Peter established the South African right whale monitoring project, now in its fourth decade, a legacy that allows us to start understanding whale recovery in relation to climate change. Peter recognised the importance of collaborative research and brought together southern right whale researchers from across the South Atlantic to investigate large scale movement patterns using photo-ID as well as initiating the first satellite telemetry work on the species. Peter also recognised the role that southern right whale biology could play in better understanding right whales in the Northern Hemisphere. He worked with, and hosted US scientists to undertake a bi-hemispheric health comparison between the thriving southern and the endangered North Atlantic, right whale species.
The recovery of southern right whales in the South Atlantic and their habitat use at South Georgia, a former epicentre of industrial whaling, are topics Peter certainly had a great interest in, and we hope to do this topic justice in his name.
Project updates can be found on our project Facebook page.