Abstract
Abstract
The rise of mercury since the Industrial Revolution is regarded as a global signature of industrialisation. We use lake sediment records from sub-Antarctic Macquarie and Campbell Islands spanning the period before and after 1850 Common Era (CE) to investigate how local colonial disturbance influences mercury sources and cycling. Although mercury accumulation increased 1.1- to 74-fold across all lakes following European arrival (1810 CE), isotope responses were lake specific. Our findings identify colonisation as an unrecognised driver of mercury cycling that can override the global industrialisation signature in the Southern Hemisphere. Colonisation-driven ecological changes, including the introduction of invasive rabbits altered mercury cycling through two connected processes. Firstly, vegetation disturbance and erosion increased catchment-derived mercury. Secondly, marine biological mercury cycling shifted to terrestrial biological cycling through food web reorganisation. These responses reveal that colonisation, primarily through the introduction of invasive species, was a significant driver of Anthropocene mercury cycling, alongside industrialisation.