Criteria for calculating the coldwater IBI.

                                                                                         Criteria for Assigning Scores

Metric                                                                       20 (Good)           10 (Fair)             0(Poor)


1.    Number of Intolerant Species                             >  2                      1                           0

2.    Percent of All Individuals that are Tolerant             0-5                     6-22              23-100  Species

3.    Percent of All Individuals that are Top                 46-100                15-45                   0-14
       Carnivore Species

4.    Percent of All Individuals that are                        86-100                 43-85                  0-42
       Stenothermal Coolwater and Coldwater
       Species (Native & Exotic)

5.    Percent of Salmonid Individuals that are              96-100                  5-95                     0-4
       Brook Trout


Notes:
A.    Stocked trout should not be included in any of the metric calculations.
B.    For metric 5, if no salmonids are captured, then the score is zero.

 
 
Classification Species
Intolerant Chestnut Lamprey (ammocoete only), Northern Brook Lamprey, Southern Brook Lamprey, Silver Lamprey (ammocoete only), Brook Trout, Muskellunge, Redside Dace, Mississippi Silvery Minnow, Speckled Chub, Gravel Chub, Pallid Shiner, Blacknose Shiner, Spottail Shiner, Rosyface Shiner, Weed Shiner, Ozark Minnow, Highfin Carpsucker, Blue Sucker, Northern Hog Sucker, Black Buffalo, Spotted Sucker, Greater Redhorse, Slender Madtom, Rock Bass, Longear Sunfish, Smallmouth Bass, Crystal Darter, Rainbow Darter, Iowa Darter, Least Darter, Gilt Darter, Slenderhead Darter, Mottled Sculpin, Slimy Sculpin, Spoonhead Sculpin, Deepwater Sculpin.
Tolerant Central Mudminnow, Goldfish, Common Carp, Golden Shiner, Red Shiner, Bluntnose Minnow, Fathead Minnow, Blacknose Dace, Rudd, Creek Chub, White Sucker, Yelllow Bullhead, Green Sunfish.
Top Carnivore Longnose Gar, Shortnose Gar, Bowfin, American Eel, Skipjack Herring, Pink Salmon, Coho Salmon, Sockeye Salmon, Chinook Salmon, Rainbow Trout, Atlantic Salmon, Brown Trout, Brook Trout, Lake Trout, Northern Pike, Grass Pickerel, Muskellunge, Channel Catfish, Flathead Catfish, Burbot, White Bass, Yellow Bass, Rock Bass, Warmouth, Smallmouth Bass, Largemouth Bass, White Crappie, Black Crappie, Walleye, Sauger.
Native Stenothermal Coolwater Northern Brook Lamprey, Southern Brook Lamprey, American Brook Lamprey, Muskellunge, Redside Dace, Lake Chub, Brassy Minnow, Northern Redbelly Dace, Finescale Dace, Pearl Dace, Burbot, Brook Stickleback.
Exotic Stenothermal Coolwater Sea Lamprey, Alewife, Rainbow Smelt, Threespine Stickleback, Ruffe.
Native Stenothermal Coldwater Cisco, Lake Whitefish, Bloater, Deepwater Cisco, Kiyi, Blackfin Cisco, Shortnose Cisco, Shortjaw Cisco, Brook Trout, Lake Trout, Pygmy Whitefish, Round Whitefish, Longnose Sucker, Ninespine Stickleback, Mottled Sculpin, Slimy Sculpin, Spoonhead Sculpin, Deepwater Sculpin.
Exptic Stenothermal Coldwater Pink Salmon, Coho Salmon, Sockeye Salmon, Chinook Salmon, Rainbow Trout, Atlantic Salmon, Brown Trout.

Guidelines for interpreting coldwater IBI scores
 

IBI Score  Integrity Rating    Interpretation and Fish Community Attributes
100-90 Excellent Comparable to the best situations with the least human  disturbance.  Mottled or slimy sculpine are common.  Intolerant, native stenothermal coolwater species such as lampreys or redside dace may also be present.  Brook trout are the top primary carnivore and are present in good numbers.  Exotic salmonids are uncommon.  Tolerant species may be present in moderate numbers.
80-60 Good Evidence for some environmental degradation and reduction in biotic integrity.  Either brook trout or sculpins may be uncommon or absent.  Exotic salmonids often dominate, keeping abundance of top carnivore high.  Tolerant species may be common, but do not dominate.
50-30 Fair The stream reach has experienced moderate environmental degradation, and biotic integrity has been significantly reduced. Total species richness is often relatively high, but intolerant and native stenothermal coldwater species are uncommon or absent.  Native stenothermal coolwater species and exotic salmonids may be moderately common, but tolerant species and/or warmwater species are usually much more abundant.
20-10 Poor  Major environmental degradation has occurred, and biotic integrity has been severely reduced.  Total species richness may be relatively high, but intolerant species, top carnivores, and salmonids are absent.  A few native stenothermal coolwater species such as brassy minnows or brook stickleback may be persist in low numbers.  Tolerant species and/or warmwater species dominate.
0 Very Poor Human disturbance and environmental degradation has decimated the natural coldwater fish assemblage of the reach.  Either only warmwater and tolerant species remain, or fish abundance is so low (<25 individuals captured) that the IBI cannot be calculated

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