Content area
Full text
Abstract - We are reporting on established populations and sightings of species in the genus Amynthas in Vermont, from Quechee (43°38'N) central-eastern Vermont to Alburgh (44°58'N) on the northwest border to Canada. To our knowledge, these are the first sightings of Amynthas spp. reported for Vermont. Invasive Asian earthworms of the genus Amynthas were found at three of twelve forested locations surveyed for invasive European earthworms. In addition, Amynthas was found in a number of horticultural settings. We evaluated soils and climate information for forested sites with Amynthas in Vermont and compared climate with the original range and more southern US sites. Our findings suggest that Amynthas may expand its range even further north than Vermont and that the freeze-free period required for maturation is approximately 90 days.
Introduction
Earthworms became extinct in northeastern North America during the last glaciation but were reintroduced by European settlers (Bohlen et al. 2004). Since then, the invasion of forests by European earthworms has played a significant role in the ecology of northeastern hardwood forests. Earthworm invasions transform and mix O and A horizons, destroying habitat for many indigenous plant species and thus reducing plant biodiversity (Hale et al. 2005, 2006). Now, a new group of earthworms of genus Amynthas, originating in east Asia, are colonizing forests in the northeastern USA (Burtelow et al. 1998) and other cold-climate environments in North America (Callaham et al. 2003, Snyder et al. 2010). These earthworms have the potential to severely impact forest ecosystems (Burtelow et al. 1998). Amynthas have been reported in North America since the 19th century (Gates 1958, Snyder et al. 2010). Their common names include Jersey Wigglers, Alabama or Georgia Jumpers, Snake Worm, and Crazy Worm which refer aptly to their snakelike, fast mode of movement and maybe also to the fracture and shedding of its tail when an Amynthas is caught. There is remarkably little known about their life-history traits. They are classed as epi-endogeic species because they live at the surface or within the top layer of the soils. A few recent studies discuss environmental tolerances (such as temperature, moisture, and acidity) on one species, A. agrestis Goto & Hatai 1899 (Bernard et al. 2009, Richardson et al. 2009, Snyder et al. 2010), but there remain...