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SIGHTINGS AND ACOUSTIC RECORDS OF RIGHT WHALES COLLECTED IN SOUTH GEORGIA (ISLAS GEORGIAS DEL SUR) WATERS JANUARY-FEBRUARY 2018

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... The 2018 survey used visual and acoustic survey techniques to locate southern right whales. Poor weather conditions limited survey effort, but southern right whales were regularly sighted in the predominantly coastal survey area to the north of the island (Jackson et al., 2018). In 2019, BAS took part in a CCAMLR synoptic krill survey of the Scotia Arc and Antarctic Peninsula region. ...
... On previous expeditions to SG, southern right whales were observed frequently performing long dives (>10mins), perhaps associated with foraging (Jackson et al., 2018). Therefore, as part of the 2020 expedition, a pole-mounted 200kHZ EK80 echosounder was deployed in the vicinity of southern right whales performing long dives to characterise the local prey field. ...
... Signals were then digitized using a Fireface UFX sound board (RME Inc.) with digital gain control set to 20 dB which equated to a maximum input level of 8.4 V peak-peak. Digitized signals were recorded and processed using PAMGuard (Gillespie et al., 2008), and the DIFAR bearings to calls resolved as described by Miller et al., (2015;, and following the same methodology as Jackson et al., (2018). Calibrated received level measurements of calls were obtained in PAMGuard by following the calibration methods described by Rankin et al., (2019). ...
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Over 170,000 whales were killed in the sub-Antarctic waters of South Georgia (Islas Georgias del Sur, SG, South Atlantic) from 1904 to 1965. In recent decades, whales are regular summer visitors, with the southern right whale (Eubalaena australis) and humpback whale (Megaptera novaeangliea) most commonly reported. A 23-day cetacean survey was conducted in SG waters during January/February 2020, using directional acoustics and visual surveys to localise whales, and collecting skin biopsies, faecal samples, photo-identifications, and blow samples for microbiome analysis. The survey focussed on southern right whales (SRW) and also collected sightings, photo-identifications and skin biopsies from other species. A total of 1,147 nautical miles of visual survey effort was conducted, and 4 prey-field surveys (totalling 34 nm) 2 using active acoustics. In total, cetaceans were encountered 540 times (521 encounters in SG waters), including southern right whales (SRW, 10 encounters of 11 individuals), humpback whales (409 encounters, ~790 individuals) and blue whales (Balaenoptera musculus, 38 encounters, ~58 individuals). Two SRW were satellite tagged and their movements subsequently tracked. Photo-identifications and biopsies were collected from southern right (11 and 7 respectively), humpback (48 and 17 respectively) and blue whales (25 and 9 respectively). Aerial imagery was collected via Unmanned Aerial Vehicles (UAVs) during four SRW, with three blow samples also collected. Additionally, one faecal sample was collected from one SRW. Overall, this expedition yielded an unprecedented number of sightings of both blue and humpback whales, suggesting that the waters of SG are once again becoming an important summer feeding ground for both species.
... The Workshop further discussed that while some telemetry studies with an excellent scientific basis can be successful and provide valuable information, the work is often not feasible to carry out due to logistical or geographical constraints. Recent work in South Georgia (Islas Georgias del Sur) provides an example of the difficulties due to the logistical, operational and environmental complexity of the prevailing field area (Jackson et al. 2018). ...
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Report of the Workshop. Please use the following citation: Carroll EL, Charlton C, Vermeulen E, Clarke P and J. A. Jackson (Eds). 2020. Roadmap to success for the International Whaling Commission - Southern Ocean Research Partnership (IWC-SORP) Theme 6 - the Right Sentinel for Climate Change: linking southern right whale foraging ecology to demographics, health and climate: Report of the Workshop. Report SC68B/SH/07 presented to the Scientific Committee of the International Whaling Commission, Cambridge, UK
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As species recover from exploitation, continued assessments of connectivity and population structure are warranted to provide information for conservation and management. This is particularly true in species with high dispersal capacity, such as migratory whales, where patterns of connectivity could change rapidly. Here we build on a previous long-term, large-scale collaboration on southern right whales (Eubalaena australis) to combine new (nnew) and published (npub) mitochondrial (mtDNA) and microsatellite genetic data from all major wintering grounds and, uniquely, the South Georgia (Islas Georgias del Sur: SG) feeding grounds. Specifically, we include data from Argentina (npub mtDNA/microsatellite=208/46), Brazil (nnew mtDNA/microsatellite=50/50), South Africa (nnew mtDNA/microsatellite=66/77, npub mtDNA/microsatellite=350/47), Chile-Peru (nnew mtDNA/microsatellite=1/1), the Indo-Pacific (npub mtDNA/microsatellite=769/126), and SG (npub mtDNA/microsatellite=8/0, nnew mtDNA/microsatellite=3/11) to investigate the position of previously unstudied habitats in the migratory network: Brazil, SG and Chile-Peru. These new genetic data show connectivity between Brazil and Argentina, exemplified by weak genetic differentiation and the movement of one genetically identified individual between the South American grounds. The single sample from Chile-Peru had a mtDNA haplotype previously only observed in the Indo-Pacific and had a nuclear genotype that appeared admixed between the Indo-Pacific and South Atlantic, based on genetic clustering and assignment algorithms. The SG samples were clearly South Atlantic, and were more similar to the South American than the South African wintering grounds. This study highlights how international collaborations are critical to provide context for emerging or recovering regions, like the SG feeding ground, as well as those that remain critically endangered, such as Chile-Peru.
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