The 2020 tohorā – southern right whale
In August 2020, researchers from the University of Auckland and Cawthron Institute, in collaboration with the Australian Antarctic Division and the US National Atmospheric and Oceanographic Administration (NOAA), put satellite trackers on six tohorā – southern right whales. Below you can meet the whales and see their tracks. All images collected under Department of Conservation permit.
Tahi the tohorā was tagged on 4 August 2020 and was an early migrator, heading southwest from the Auckland Islands Maungahuka on 7 August. Tahi passed close by Macquarie Island, reaching 58°S before heading north. The sinuous tracks southwest of Australia suggest Tahi spent about 40 days feeding before continuing west. Tahi went about half way to South Africa, before heading back west, completing a giant donut in the ocean south of Australia. Tahi’s last transmission was 30 March 2021, for a total of 237 days of tracks.
Rua the tohorā was tagged on 5 August 2020 and stayed around the Auckland Islands Maungahuka for almost the full 40 days its tag was transmitted. Rua made a brief , 100 km excursion offshore in early August, and the tag stopped transmitting on 13 September 2020.
Toru the tohorā was tagged on August 5 and hung around Port Ross for about 50 days. At the end of September, Toru migrated in southwest to as far as 53°S, at which point it turned northwest, ending up ~1,000km south of Australia. Toru spent 86 days in an area ~600km across in E-W direction where its tracks were highly sinuous, indicative of feeding behaviour. While still in this area, Toru’s tag stopped transmitting on 22 January 2021, 169 days after deployment.
Whā the tohorā was tagged on 7 August 2020, circumnavigated the Auckland Island Maungahuka and visited Campbell Island Motu Ihupuku before migrating south. Whā continued moving southwest and west around latitude 60°S, after which it stated making its way in a more northwesterly direction. Whā’s tag stopped transmitting on the 5th of October 2020 (60 days since deployment) at which point Whā was ~1,700km south of Australia.
Rima the tohorā was tagged on 7 August 2020, and like Toru and Rima, took a short journey offshore from the Auckland Island Maungahuka. Rima began migrating southwest on 16 August 2020, and reached latitude 58°S, at which point it started migrating in a more north-westerly direction towards Australia. Rima’s tag stopped transmitting on 21 October 2020 (76 days after deployment), at which point Rima was ~1,050km south of the south-west tip of Australia.
Bill or Wiremu the tohorā is a friendly whale that hung around the yacht Evohe, often resting its head on the seafloor. Genetic analysis of a small skin biopsy sample taken from Bill shows the he is a male, and had been in the Auckland Islands Maungahuka for at least two weeks before he was tagged on 17 August 2020. Bill’s southward migration began on 22 August 2020, and he reached latitude 56°S at which point he began to travel northwest. Bill ended up ~570km south from the southwest tip of Australia where its track became highly sinuous between 1 and 28 October 2020, indicative of foraging behaviour. Bill then continued moving west and later southwest, occasionally having highly sinuous tracks. around longitude 80°E Bill began travelling almost directly south, passing ~610km east of the Kerguelen Islands. Bill then headed south and has been tracking 200-300 km north of the Antarctic continent in a westward direction. As of 6 April 2021, Bill’s tag had been transmitting for 232 days and we are hopeful we continues to come home to the Auckland Islands Maungahuka.