The introductions of predatory carabid beetles such as Trechisibus antarcticus to South Georgia may provide an illustration of the potentially rapid ecosystem changes caused by the introduction of foreign species. They also provide a form of natural experiment testing ecological theories about the consequences of introducing new trophic levels into natural ecosystems which would otherwise be impossible (Convey et al. 2006a).
In South Georgia, sub-Antarctica, Trechisibus antarcticus is invading the coastal lowland areas and building up local high densities in the dominant tussock-forming grass Parodiochloa flabellata (Ernsting et al. 1999). Together with an ample food supply in the form of small arthropods and beetle larvae and a vacant niche for arthropod predators, the benign microclimate of the tussock vegetation may explain the success of this and similar predator beetle introductions in South Georgia (Brandjes Block & Ernsting 1999). Compared with other habitats, tussock provides a buffered and stable thermal regime that will facilitate the spread of T. antarcticus throughout the lowland areas (Brandjes Block & Ernsting 1999).
Laboratory experiments have shown that the carnivorous Trechisibus antarcticus is a voracious predator, feeding on beetle larvae and other soil arthropods (Ernsting et al. 1999). T. antarcticus feeds on various mites and springtails the larvae of the herbivorous beetle Hydromedion sparsutum on South Georgia (Todd 1997).
Compiler: IUCN SSC Invasive Species Specialist Group (ISSG) with support from the EU-funded South Atlantic Invasive Species project, coordinated by the Royal Society for the Protection of Birds (RSPB)
Publication date: 2009-04-27
Recommended citation: Global Invasive Species Database (2021) Species profile: Trechisibus antarcticus. Downloaded from http://www.iucngisd.org/gisd/species.php?sc=1454 on 28-09-2021.