Beltrami Aquatic Invasive Species Task Force                    
Relative Risk Assessment Matrix (Preliminary Draft)    
  Damage potential Difficulty of       Sum Risk Rank    
Hyperlinked version available on-line at WaterBlog: beltramiswcd.blogspot.com See also www.seagrant.umn.edu/ais/ Fisheries Water Quality Economic Ecological Detection Prevention Containment Eradication Pervasiveness Rate of Spread Proximity Factor   First noted Notes
Animals                      
Bighead/Silver carp 4 4 3 4 3 4 5 6 2 3 3 41 21 ~1970  
Chinese mystery snail 2 2 4 3 2 6 6 8 8 6 10 57 15 1931 PRESENT Widespread
Common carp 5 7 6 7 3 4 6 8 7 5 7 65 8 1879  
Grass carp 4 6 4 7 2 6 5 6 2 3 3 48 17 ~1960  
New Zealand mud snail 5 5 5 5 6 6 7 8 3 5 5 60 13 1991 Asexual, very high density
Round goby 7 5 5 7 5 4 7 8 3 3 4 58 14 1990  
Ruffe 7 5 5 5 7 6 8 8 6 5 4 66 7 1986  
Rusty crayfish 7 5 8 8 4 5 6 8 6 6 10 73 2 -- PRESENT eat fish eggs, destroy vegetation
Sea lamprey 6 2 6 5 3 3 3 5 4 3 4 44 19 --  
Spiny waterflea 7 4 8 9 7 7 9 9 6 8 6 80 1 1982 Cook, St. Louis, Lake of the Woods
White perch 5 3 4 4 4 4 5 8 3 3 3 46 18 1950  
Zebra mussel 5 4 6 8 6 6 7 8 6 5 6 67 6 1988 Crow Wing, Mille Lacs
Plants                              
Curly-leaf pondweed 3 8 7 6 4 4 7 8 4 5 9 65 8 1879 Present? Hubbard (early growth, mats, & senesence)
Eurasian milfoil 3 5 8 6 4 5 8 8 8 6 8 69 4 1952 Cass, Itasca
Flowering rush 3 3 4 5 4 3 4 5 3 7 8 49 16 1905 Itasca County
Purple loosestrife 4 5 5 6 3 5 6 7 8 6 10 65 8 1869 PRESENT: Wetland competitor
Reed canary grass 2 3 3 6 2 4 5 6 5 6 2 44 19 ~1850  
Yellow iris 2 3 3 4 2 3 4 4 3 4 2 34 22 1886  
Other                              
Bacterial kidney disease 6 4 6 6 7 5 7 7 6 6 4 64 11 1975 Devastating for trout and other salmonids (cisco?)
Heterosporis 7 5 6 5 5 5 7 7 6 8 10 71 3 2002 PRESENT In Lake Bemidji (Cloutman), Cass Chain
VHS Novirhabdovirus 8 4 7 6 8 7 8 9 3 6 2 68 5 2005 Low probability but high impact (20-80% mortality)
Ranavirus (LM Bass) 6 4 4 5 7 7 8 9 5 5 2 62 12 2002  
Each species ranked for each item on a 1-10 scale with 1 being minimal risk and 10 being extreme risk      
Note numerous algae and microinvertebrates not listed    
Proximity factors add 10 for already present, 8 for adjacent county, 6 for inland Minnesota, 4 for Lake Superior, 2 for Great Lakes