Anglers should know that all of the earthworms they use for bait, including angle worms and nightcrawlers, are invasive to Minnesota and Wisconsin and can do damage to local ecosystems.

There have been no native earthworms in the Northland since the Ice Age.

State officials in Minnesota and Wisconsin in recent days reminded anglers to throw all leftover bait in the trash so as not to speed the spread of the invaders, although most areas of Minnesota and Wisconsin already have been colonized. Worms are causing damage in wooded areas because they eat the duff layer, leaves and other stuff right on top of the soil. Their damage reduces habitat, causes soil compaction and erosion and can even change what types of trees and plants will grow in an area.

'Jumping worm' invasive species arrives in Minnesota, Wisconsin

Now there’s another worm to be aware of, the agencies noted, often called the "jumping worm" because of its erratic movements. The News Tribune first reported on the new invader last October. There are several species, all in the amynthas family.

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Jumping worms are showing up in southern Minnesota and southern Wisconsin (so far), hitchhiking in bags of commercial mulch, compost, soils and potted plants shipped in from other states. Gardeners who have jumping worms may notice wilted plants. Upon closer inspection, the plants are no longer attached to the soil and the soil has been altered to look like coffee grounds. Most plants can't grow in this soil, so they die.

“Jumping worms are a relatively new invasive species in Minnesota and they are a threat to gardens and forests,” said Laura Van Riper, Minnesota Department of Natural Resources terrestrial invasive species coordinator. “They make rich soil more like coffee grounds. They eat plant roots, damaging garden plants and sod.”

Native to Asia, jumping worms have been confirmed in limited areas of Minnesota since 2006, mainly in the Twin Cities western suburbs and in Rochester. In southern Wisconsin, jumping worms were recently found by inspectors in the growing area of a Columbia County nursery near Madison.

The 1.5- to 8-inch-long worms can be identified by the smooth, whitish non-segmented band around the body. Other common worm species have a raised band. Anglers trying to use jumping worms as bait will quickly notice their movement and tendency to break into segments when handled.

“The good news is, jumping worms are not well-established in Minnesota and there are actions people can take to prevent their spread. We need gardeners and anglers to be vigilant and to contact the DNR when they think they’ve found jumping worms,” Van Riper said.

Other steps that help:

  • Don’t buy worms advertised as jumping worms, “snake worms,” “Alabama jumpers” or “crazy worms” for any purpose.

  • Anglers should dispose of any unwanted bait worms in the trash.

  • Gardeners should inspect incoming mulch or plants for jumping worms and if swapping plants with friends, wash off the soil and share the plants as bare-root plants.

  • Recreationists should brush the mud off their boots and equipment.

If you are sure you have jumping worms in Minnesota, call 888-646-6367 or email high-resolution photos to info.dnr@state.mn.us.