Hatch Chart for Fly Fishing | Western United States

Hatch charts can help you pick out the appropriate flies and tackle that you are likely to need for an upcoming fly fishing trip. They should never be taken as gospel, but rather as a general guide to expected aquatic insect activity. Weather and water conditions can cause significant changes in the timing and duration of the hatches, but in the Western United States they usually happen in the same order each year.

Click on the links for each fly to take you to our favorite recommendations for imitating a specific insect. You can then purchase the right flies for a hatch, or if you are a fly tier, you will find the pattern listing for these flies. Note that many of the patterns are offered in different sizes; choose the sizes listed on the hatch chart for the most accurate imitation.

If you’d rather purchase flies in prepared selections, we offer the following hatch-specific fly selections:

Terrestrial Fly Selection Western Trout Summer Fly Selection
Prince Fly Selection  

Your best source for current information will be a local company-owned retail store or Orvis dealer.

Click Here to view Hatch Charts for the Eastern and Mid-Western United States

 

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                

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Trout love this life-like Mayfly Emerger This midge fly pattern can be used as a dry fly or emerger. Imitate various hatches with these big trout dry flies.

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