Positive feedback between invasive species in a sub-Antarctic ecosystem: a case of invasional meltdown?

This repository contains the data used in the manuscript “Positive feedback between invasive species in a sub-Antarctic ecosystem: a case of invasional meltdown?”.The dataset is organised into two sheets:Metadata — provides variable names, definitions, and units.Data — contains the field and laboratory measurements used for all analyses reported in the manuscript.Study contextThe study was conducted on South Georgia (54°26’S, 36°33’W) to evaluate the direct and indirect effects of the invasive grass Poa annua on the invasive predatory beetle Trechisibus antarcticus. We measured beetle abundance, morphology, physiological stress responses, and microhabitat thermal buffering across three microsite types (P. annua turfs, Poa flabellata tussocks, and bare soil).MethodologyField sampling followed a standardised protocol in which beetle abundance was quantified through repeated visual censuses (seven 10-minute periods per sampling point), and at least three T. antarcticus individuals were collected per sampling point for morphological and physiological measurements. Body mass and body length were measured in the field, substrate temperature and thermal decoupling were also recorded in situ using digital thermometry paired with adjacent sandy controls. Hsp70 concentrations were quantified using an ELISA protocol applied to pooled beetle samples from each microsite. Full methodological details for all procedures, including statistical analyses, are provided in the Methods section of the main manuscript. The complete ELISA workflow and laboratory procedures for Hsp70 determination are provided in the Supplementary Material.