Several species of jumping worms (Amynthas spp.) have been found in North America. Jumping worms have earned this common name because they will thrash around like angry snakes when moved. This is unlike our naturalized European earthworms (Lumbricus spp.) which will just curl up when disturbed. Distinguishing traits between the invasive jumping worms and naturalized European earthworms is vital to stopping the spread of jumping worms. Both worms have a collar-like structure called a clitellum which is present near their head, but invasive Amynthas spp. have a white clitellum that fully encircles the worm and is flush with the worm body. For Lumbricus spp. the clitellum is pink, only partially covers the worm and is raised like a saddle. Invasive jumping worms are also dry and smooth and not slimy and floppy like European earthworms.
Larval Amynthas spp. will not have the clitellum present, so identification relies on the texture of the worm and its characteristic movements. Development from hatchling to adult is estimated to be a minimum of 90 days, based on frost-free periods of invaded locations.
Ecological Threat: Unlike our European naturalized earthworms (Lumbricus spp.) that mill through the dirt and excrete nutrients back into the soil after digestion; these invasive jumping worms consume all organic matter and leave no nutrients for the plants. Furthermore, this causes severe degradation of the topsoil which also leads to plants being uprooted. They have been documented to cause significant damage to forested areas including the complete loss of topsoil needed by native wildlife and plants to thrive. Because of their ability to completely change the soil composition, another distinguishing trait that would confirm their presence is soil looking like coffee grounds.
Biology: Amynthas jumping worms inhabit the soil surface directly below the leaf litter layer, rather than dwelling in deeper soil layers like European earthworms. They are self-fertilizing (parthenogenic) and have an annual life cycle that causes them to mature at the same time near the end of summer. Overall juvenile worms can be found April-June and adults are found June-December. Each new generation begins with the production of hardened egg capsules, known as cocoons. Cocoons will overwinter in the soil which has led to their success in northern states, and they are also drought resistant. Thankfully, cocoons will not survive the temperatures used in treatment commercial composting.
History: Like many soil-dwelling organisms Amynthas jumping worms hitchhiked to the United States in potted plants. They were first documented in the Northeastern United States in the 1910s. Reports from New York in the 1940s recorded them in horticultural areas and zoos. They have been able to spread throughout the United States through potted plants and as fishing bait. Studies have shown that Amynthas diffringens was reported from Nacogdoches County, TX as early as 2004.
U.S. Habitat: Like other earthworms Amynthas jumping worms are soil-dwelling creatures and have shown adaptability for hard winters and drought periods. They will be found in the topsoil layers where leaf litter is present, unlike European earthworms which inhabit deeper layers of soil.
Native Origin: North-central Asia
U.S. Present: Confirmed reports from: CT, DE, GA, IN, KY, MA, MD, ME, MN, NC, NH, NY, OH, OK, PA, SC, TN, TX, VA, VT, WI and WV. Suspected to be present in more states.
Distribution in Texas: These worms are expanding into Texas, and we need help from citizens to report distributional information. Citizens have helped report this worm from central, north and east Texas. It is highly likely the worm is spread throughout the state.
If you suspect a jumping worm, REPORT this species here.
It can be confused with European earthworms (Lumbricus spp.). The differences are in their movement, color and appearance of the clitellum and the presence of soil that looks like coffee grounds
It is very important to note that while European earthworms are naturalized and readily used in garden and agricultural settings, they will also cause harm to our forested areas. If you are using European earthworms, please keep them focused in your area and never release them into wooded areas or aquatic habitats. Unfortunately, there are no recommended control measures for jumping worms beyond hand removal and disposal in the trash. Chemical treatments that would kill jumping worms would also kill earthworms and other beneficial soil organisms.
Preventative: Check the mulch, potting soil, compost, and any potted plants you bring home for worms. If you identify jumping worms, immediately bag up the material and dispose of it. You do not want to put any of it in your garden! Remove soil from all plants before transporting them or potting into sterile potting soil. This helps to remove jumping worm cocoons (egg cases). PLAY, CLEAN, GO: Leave no trace and clean equipment (gardening, hiking, etc.) before going to another location.
Cultural: If you use any type of worm for fishing it is also important to never dump your unwanted bait into the water or on the shores of where you are fishing. Please dispose of them properly by placing them in a sealed bag and then within the trash. DO NOT BUY worms advertised as jumping worms, snake worms, or Alabama jumpers for any purpose. If you are a composter, it is vitally important that you are aware of what species of earthworms you are bringing back to your composting areas. Use a compost or mulch supplier that follows the process for further reducing pathogens method. This ensures that compost reaches 131 degrees or above and involves turning compost piles on a schedule. If the facility is following that process, it likely kills jumping worms and their eggs. It is also recommended you freeze your vermicompost for one week before spreading it in your yard. This will kill any jumping worms or eggs hidden within the compost.
Chang, C.H., Johnston, M.R., Gorres, J.H., Davalos, A., McHugh, D. and Szlavecz, K., 2018. Co-invasion of three Asian earthworms, Metaphire hilgendorfi, Amynthas agrestis and Amynthas tokioensis in the USA. Biological invasions, 20(4), pp.843-848.
Damoff, G.A. and Farrish, K.W., 2005, November. Are east Texas bottomland forest soils being re-engineered by the exotic invasive earthworm Amynthas diffringens (Baird, 1869). In American Society of Agronomy International Annual Meetings (pp. 192-9).
Laushman, K.M., S.C. Hotchkiss, and B.M. Herrick. 2018. Tracking an invasion: community changes in hardwood forests following the arrival of Amynthas agrestis and Amynthas tokioensis in Wisconsin Biological Invasions 20(1671-1685).
Schult, N., K. Pittenger, S. Davalos, and D. McHugh. 2016. Phylogeographic analysis of invasive Asian earthworms (Amynthas) in the northeast United States. Invertebrate Biology 135(4):314-327.
Snyder, B.A., M.A. Callaham Jr., and P.F. Hendrix. 2011. Spatial variability of an invasive earthworm (Amynthas agrestis) population and potential impacts on soil characteristics and millipedes in the Great Smoky Mountains National Park, USA. Biological Invasions 13(349-358).