Published article on deglaciation and peat formation on sub‐Antarctic Marion Island
Twenty‐thousand‐year gap between deglaciation and peat formation on sub‐Antarctic Marion Island attributed to climate and sea level change
Article published by Werner Nel, Dominic Hodgson, David Hedding, Alex Whittle and Elizabeth Rudolph
Radiocarbon dating of basal peats has been a key factor in determining minimum ages for deglaciation on sub‐Antarctic islands. On Marion Island, peat bogs dominate the landscape below 300m a.s.l., and palynological assessments of peat cores have been used to assess the vegetation history and succession rates as well as the sensitivity of the indigenous flora to climatic change. Initiation of peat on the sub‐Antarctic islands signifies a major landscape change which has previously been linked to the retreat of glaciers. Here we test this hypothesis by comparing previously published and new basal peat ages from Marion Island with cosmogenic isotope dates for deglaciation, and local and regional palaeo‐environmental changes. Results show that, in common with other sub‐Antarctic islands, peat initiation occurred after the Antarctic Cold Reversal (15–13 ka) and through the early Holocene climate optimum. This substantially postdates cosmogenic isotope evidence for deglaciation from the basalts which shows that the areas where the peatlands dominate were ice‐free from the start of Marine Isotope Stage (MIS) 2 (~31 ka). This suggests that environmental conditions controlled peat initiation rather than deglaciation. Regional climatic proxies show that during and after MIS 2, extremely low temperatures, extensive sea ice conditions and depressed sea surface temperatures together with lower sea levels at an island scale could have maintained conditions unfavourable for peat initiation at their current locations. On Marion Island, the significant gap of ~20 000 years between the timing of deglaciation and peat formation indicates that the use of peat basal ages as a proxy for the minimum age of deglaciation in the sub‐Antarctic should be used with extreme caution.
Left( Werner Nel, David Hedding and Elizabeth Rudolph)
© 2024 The Author(s). Journal of Quaternary Science Published by John Wiley & Sons Ltd.
The Agreement on the Conservation of Albatrosses and Petrels (ACAP) has announced that “Marine Protected Areas – Safeguarding our Oceans” is to be its theme for this year’s 
Marion Island and Prince Edward Island, collectively known as the Prince Edward Islands, are tiny specks of land in the Southern Ocean, the huge body of water that encircles the Antarctic Continent. Marion Island is the larger of the two islands, with an area of just under 300 square kilometres, whereas Prince Edward Island is considerably smaller – a mere 45 square kilometres. With a summit of 1 230 metres Marion Island is also much higher than the 672-metre high Prince Edward Island. The two islands are close neighbours, with only 19 kilometres of relatively shallow water separating them.
The Prince Edward Islands, together with the other islands within the Southern Ocean, form part of a complex and productive ecosystem that has far-reaching influences. In turn the ocean dominates many aspects of the islands, from the way the vegetation grows to climate and geomorphology. The islands rose above the surface of the ocean after a prolonged period of underwater volcanic activity and the rocks and many of the landscapes reflect these tumultuous beginnings. From the jagged, almost surreal expanse of the black lava fields, to the many red scoria cones that dot the landscape, these volcanic origins are responsible for some of the most striking natural features of the islands. Despite the fact that today, researchers and managers visit them every year the islands still remain one of the wildest places on earth.
Text from: Publication Marion and the Prince Edward. 
ABOVE: Michelle Jones (M80), Vanessa Steven (M81), Prof Susie Cunningham (UCT FitzPatrick PI), Rhiannon Gill (M81), Prof Peter Ryan (UCT FitzPatrick), Chris Jones (M80)
Above: Chris and Michelle Jones working with the Wandering Albatross during overwinter period
(left) Michelle Jones with Grey-headed Albatross and (right) Chris Jones with Common Diving Petrel
(Above: Azorella selago – left: intact, right: eaten by mice)
(Above: Elmar van Rooyen and Rabia Mathakutha. Left: before departure. Right: On board S.A.Agulhas II with Marion Island in the back)
Allow me to introduce myself briefly. I am a 29-year-old conservation ecologist with a profound passion for nature and exploration. I hold an M.Sc. degree in Conservation Ecology & Entomology and possess a diverse skill set that includes expertise in ecology, restoration ecology, horticulture, botany, entomology, education, and management. Throughout my career, my focus has predominantly been on Southern Afrotemperate forests, and I have accumulated significant experience in South African forest ecology. I am drawn to this expedition for several reasons. Foremost, the opportunity to explore the unique environment of Marion Island presents a once-in-a-lifetime chance for me to expand my knowledge and understanding of sub-Antarctic ecosystems. While I may not have prior experience with the island, I firmly believe that firsthand experience is the most effective way to comprehend its ecology and wildlife. Moreover, I am deeply committed to the conservation of natural habitats, and Marion Island’s status as a biodiversity hotspot underscores the urgency of our research efforts. The presence of invasive house mice poses a significant threat to the island’s flora and fauna, necessitating thorough investigation and potential eradication strategies. Additionally, I am eager to contribute to studies on the impact of alien plant species and assist in devising methods for their control. I have always had a profound appreciation for fieldwork, and I relish the opportunity to immerse myself in hands-on research once again. Marion Island’s rugged terrain and unique challenges excite me, and I am prepared to tackle them head-on in the pursuit of conservation objectives.
Rabia is excited to participate in the 2024 Marion Island Relief Expedition. Rabia is an ecologist by training and will be working as part of the University of Pretoria research team towards a comprehensive understanding of impacts of the invasive house mouse on the terrestrial biodiversity of Marion Island. Rabia first visited the island as part of her Masters research project during the 2015 and 2016 relief expeditions. Rabia’s MSc in Plant Science was focused on understanding plant invasion potential and environmental change responses in the sub-Antarctic region, using Marion Island as a case study. This is when her passion for understanding and participating in the conservation of South Africa’s polar environment was ignited. In her current capacity, Rabia is a research coordinator for the Data, Products and Society (DPS) Integrated Facility of the South African Polar Research Infrastructure (SAPRI). She continues to support the polar research environment by ensuring coordinated access to research infrastructure and societal benefits through science engagement and science communication. Rabia views this chance to revisit the island as a once-in-a-lifetime opportunity, one that will not only build upon previous efforts in understanding plant dynamics but also advance our understanding of ecological processes in response to a threatening invader. There’s no better place to study this than Marion Island, our own natural laboratory, and where it’s most urgently needed. As part of the larger Mouse-Free Marion project, Rabia considers this as a significant contribution to global conservation efforts, and in her words, “saving the world!”.
From the Editor: “We would like to dedicate the third and final issue of M80’s cohort of the Wanderer to M81. Marion is anything you want it to be, so make it special. It goes quick.” = Zafier Maurier (right)
