The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
In 65 records from GBIF, adults of this species have mostly been collected during April (23%), May (23%), October (12%), March (9%), September (8%), June (8%), and December (6%).
In 32 records from GBIF, this species has been collected at elevations ranging from 156 to 11499 ft, with an average (median) of 6079 ft.