Summary
The sub-Antarctic region between 45-60°S is primarily ocean. However, there are a few small isolated islands, most of which are currently facing the combined pressures of climate change and introduced species. Many meteorological observations indicate increasing wind speed and temperature since the mid 20th century, however the extent is not uniform across the region and a lack of data mean regional generalisations are difficult to establish. When the islands were discovered by humans in the 1800s, many were initially exploited for their natural wildlife resources, animals were introduced as additional food sources/for farming purposes and many plant species were inadvertently or deliberately introduced. This has led to dramatic ecosystem changes. Nevertheless many of the islands are now recognised for their intrinsic values, having been formally recognised as World Heritage Areas. Extensive efforts have or are being made to remove their feral animals, but a lack of baseline data on natural climate and ecosystem variability means it is not possible to place observed climate changes into context and it is difficult to identify realistic baselines as a means for assessing ecosystem recovery. Using a multiproxy approach combining palaeoclimate and palaeoecological records from multiple sub-Antarctic islands (i.e. Campbell, Macquarie and Marion Islands), this project aims to develop a regional understanding of past climate and ecosystem variability. In particular, this project aims to: determine changes in the westerly winds during the Holocene and how this influences precipitation and temperature regimes over time; determine whether the timing and extent of changes varies spatially in the region; assess how changes in climate influence sub-Antarctic freshwater ecosystems; and determine whether changes in the 20th century were of similar rate and magnitude to other periods in the last 10000 years. Preliminary results from Macquarie and Campbell Islands will be presented.