invasive inverts

MAISRC focuses its research efforts on species that have been prioritized based on their proximity to Minnesota, pathway of spread, and impact. This list of high risk/high priority species is updated annually with the help of a 9-member inter-organizational Technical Committee (MTC) and with input from the Center’s Advisory Board and the Center’s faculty members.

Active research is underway at MAISRC on many of these species. We will expand our research to additional priority species as funding and partnership opportunities become available.


MAISRC high-priority species:


Species established in Minnesota with known high risk of spread and high impact:

  • Spiny waterflea (Bythotrephes longimanus)
  • Zebra mussel (Dreissena polymorpha)
  • Quagga mussel (Dreissena rostriformis)
  • Faucet snail (Bithynia tentaculata)

Species established in Minnesota but with uncertain likelihood of spread and/or level of impact:

  • Rusty crayfish (Orconectes rusticus)
  • New Zealand mudsnail (Potamopyrgus antipodarum)
  • Red Swamp crayfish (Procambarus clarkii)

Species not known to be present in Minnesota, pathway risk is unknown, but high-impact elsewhere: 

  • Ponto-Caspian amphipod (Echinogammarus ischnus)
  • Killer shrimp (Dikerogammarus villosus)
  • Caspian mud shrimp (Chelicorophium curvispinum)

Species currently being researched at MAISRC:

Zebra mussels

Zebra mussels (Dreissena polymorpha) are one of the most widespread invasive freshwater animals in the world. Their huge populations attach to hard surfaces, clog intake pipes for water treatment and power generating plants, encrust boat motors and hulls, and their sharp shells cut swimmer’s feet. They can smother and cause extinctions of native bivalve mollusks. Learn more.

zebra mussel

Spiny waterflea

Spiny waterflea (Bythotrephes longimanus) are a microscopic freshwater zooplankton that invade lakes and can take over the bottom of the food chain, disturbing the ecology of the lake and presenting a serious potential threat to Minnesota lakes. They can decimate populations of Daphnia and other native zooplankton resulting in a decreased food source for native fish and an increase in algal blooms. They can also clog the eyelets of fishing rods, causing problems for recreationalists. Learn more.

spiny waterflea