FISH ABUNDANCE RATINGS. Abundance of fish refers only to adult fish, or in the 

 case of game and sport fish to keeper size (7" minimum for trout; exception 6" 

 minimum for trout populations which spawn when shorter than 7"). By nature, 

 abundance ratings are subjective. Since trout command the most interest of 

 Montana fishes, the abundance ratings for all fishes are geared to trout. The 

 abundance graph (Figure 1) is a guide to numbers associated with abundant, 

 common, uncommon and rare. The ratings reflect the peak abundance during the 

 year, e.g., when migratory spawners are present. 



A = Abundant 



B = Abundant with proportional number of large-size fish (see criteria for 



large-size fish) 

 C = Common 

 D = Common with proportional number of large-size fish (see criteria for 



large-size fish) 

 U = Uncommon 

 V = Uncommon with proportional number of large-size fish (see criteria for 



large-size fish) 

 R = Rare 



E = Presence not verified but expected 

 I = Immature fish only; adults never in reach 



M = Species absent but might be present if habitat problems corrected 

 N = Not present 

 P = Species absent, but could be present if introduced (e.g., potential 



habitat in a barren stream) 

 Z = Abundance unknown 



MONTANA FISHES OF SPECIAL CONCERN 



Class A — limited numbers and/or limited habitats both in Montana and 



elsewhere in North America; elimination from Montana would 

 be a significant loss to the gene pool of the species or 

 subspecies . 



White sturgeon (Acipenser transmontanus ) 



Pallid sturgeon (Scaphirhynchus albus ) 



Paddlef ish (Polyodon spathula ) 



Yellowstone cutthroat trout (Salmo clarki bouvieri ) 



Westslope cutthroat trout (Salmo clarki lewisi ) 



— includes upper Missouri cutthroat trout 

 Arctic grayling (Thymallus arcticus ) 



Class B — intermediate between classes A and C. Limited numbers and/or 

 limited habitats in Montana; fairly widespread and fair 

 numbers in North America as a whole. Elimination from 

 Montana would be at least a moderate loss to the gene pool 

 of the species or subspecies. 



Native rainbow trout (Salmo gairdneri ) 

 Bull trout ( Salvelinus conf luentus ) 

 Sturgeon chub (Hybopsis gelida ) 

 Sicklef in chub (Hybopsis meeki ) 



Class C — limited numbers and/or limited habitats in Montana; 



widespread and numerous in North America as a whole. 

 Elimination from Montana would be only a minor loss to the 

 gene pool of the species or subspecies. 



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