Dr Leena Riekkola, the University of Auckland, has been awarded a Rutherford Foundation Postdoctoral Fellowship for research titled: Tohorā – southern right whales as a sentinel for ocean change: the past, the present and the future
The Southern Ocean (SO) is changing rapidly due to a variety of human impacts, including climate change and ocean pollution. These changes carry unknown current and future consequences for the ecosystems that support taonga species and fisheries in and around Aotearoa. Much of the SO near Aotearoa such as the subtropical convergence zone (STCZ), remain poorly studied, therefore assessing and mitigating impacts on the ecosystem is challenging.
Recent technological advancements, including satellite tracking, now allow researchers to use marine predators as marine sentinels or protectors by remotely following them and assessing their habitat use in relation to current and future environmental variables. In this Rutherford Foundation Postdoctoral Fellowship, Dr Riekkola proposes to use the southern right whale tohorā, a large migratory whale, to study oceanic changes across a large spatial and temporal range, with a focus on the STCZ. This will be done using a unique, international dataset of satellite tracks for the species, deployed on three wintering grounds between 2001- 2023.
Dr Riekkola will first create movement and habitat models for tohorā to investigate their habitat use and foraging ecology on a SO scale. She will then compare the modern tohorā distribution and foraging habitat with those inferred from historical whaling data to document changes in key STCZ habitats over two centuries. Furthermore, by using the habitat models to make future predictions of tohorā habitat use, Dr Riekkola will investigate how their distribution might further change in the future, both across the SO and within Aotearoa waters.
As indicator species, what we learn about tohorā will have implications for other species that use the sub-Antarctic islands of Aotearoa and their surrounding waters. By studying tohorā across an unprecedented time period, combining historical and modern data and future predictions, the mahi of Dr Riekkola showcases them as a compelling model animal to investigate the impacts of climate change.