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Hatch Chart for Western Trout-stream Insects

Western Fly Hatches
Common Name (Latin Name) Fly Size Recommended Fly
(click on fly name to view) 		Mar Apr May June July Aug Sept Oct
Midge (Chironomidae)
16-26

Nymph

  
 
Western March Brown (R. morrisoni)
12-14                
 
Little Olive (B. tricaudatus)
16-20                
Brachycentrus Caddis (various)
12-18        
Slate Gray Dun (E. longimanus)
12-14                
Pale Morning Dun (E.infrequens /inermis)
14-18        
Salmon Fly (P. californica)
4-8                
Rhyacophila Caddis (various)
12-16      
Western Green Drake (D. grandis)
10-12              
Brown Drake (E. simulans)
8-10                
Small Western Drake (E. flavilinea)
14-16              
Spotted Sedge (H. occidentalis)
14-16                    
Slate Cream Dun (E. albertae)
14-18                
Western Red Quill (H. elegantula)
14-16                
Speckle Wing Quill (C. coloradensis nigritus)
14-16                
Western Gray Drake (S. occidentalis)
10-12                  
Trico (T. minutus)
20-24          
Blue Winged Olive (B. parvus)
18-22  
Mahogany Dun (P. bicornuta)
18-20                
Tiny BWO (P. edmundsi)
20-24