This project includes the first ever dedicated survey of southern right whales on their feeding grounds off South Georgia, and runs from May 2017 to April 2019. We want to find out how many are using these waters, where they are feeding, what they are feeding on, and how healthy they are and how they link back to winter breeding areas, given big recent mortalities of calves on their calving grounds in Argentina. It is a multi-disciplinary project led by Dr Jennifer Jackson at the British Antarctic Survey. We undertook a field season to South Georgia Jan/Feb 2018; you can read more about it at our project website.
The South Georgia marine ecosystem is globally recognised as a biodiversity hotspot, and its waters are one target of a growing krill fishery. This sub-Antarctic island was also once the epicentre of modern whaling in the Southern Hemisphere (1904-1965), with over 176,000 whales killed in its coastal waters. South Georgia’s remote beaches are still littered with whalebones and the remains of whaling paraphernalia, as you can see below.
Photo: E L Carroll
Whaling off South Georgia was very intense, primarily killing fin, blue and humpback whales. Not many right whales were caught during this period, because they had already been decimated as early as the 1850s by whaling along the coast of Brazil and Argentina, and offshore in the lower latitudes of the South Atlantic. Right whales swam slowly, floated when struck, liked calm nearshore waters for calving and yielded high-value oil, making them an early and convenient (‘right’) target for whalers for many centuries. In the Southern Hemisphere, southern right whales suffered >350 years of exploitation and are now slowly recovering. Today, southern right whales are the most commonly seen whale in South Georgia waters, an area which is thought to be one of their primary feeding grounds.
Right whales feeding in South Georgia waters in summer have been linked, through photo-identifications and satellite tagging, to their calving ground at Península Valdés in Argentina, showing a migratory connection between the two areas. However the Península Valdés calving ground has had notably high calf mortalities in the last decade. A growing body of evidence suggests that South Georgia environmental conditions directly influence the low latitude population dynamics of these whales, suggesting foraging success is a primary factor influencing reproductive rates.
- Satellite tracks, acoustic and oceanographic data will be integrated to identify key areas of whale habitat use and foraging patterns in the South Georgia marine ecosystem. A report summarising these findings will be presented to the Government of South Georgia, assessing how well MPA boundaries and fishery closure timings match the patterns of right whale feeding and habitat use in these locations.
- Whale prey and habitat use in relation to the krill fishery and in relation to key oceanographic features will be investigated. Results will be reported to the annual scientific meeting of the Convention for the Conservation of Antarctic Marine Living ResourcesScientific Committee in order that right whales can be considered in spatial krill fishery management plans and ecosystem model development.
- Migratory connections between South Georgia waters and calving grounds off Argentina and Brazil will be investigated using photographs, genetics and satellite tracking, linking individuals between regions to measure long-term sightings records and reproductive histories in Península Valdés.
- Collect biological data (skin samples, body images and whale blow samples) on health and body condition to infer habitat quality during the feeding season and improve understanding of the causes of calf mortality associated with this feeding ground.