Update: Jonathan Pelham has confirmed that these are Large Marbles Euchloe ausonides, but the subspecific identity is uncertain at this time.
These three Marbles Euchloe were seen flying patrol routes along the low-point on the side of the Glenn Highway at Sheep Mountain Lodge on June 01, 2008. The gravel road bank at this point had numerous dandelions flowering, and each Euchloe occasionally stopped to feed on them - but otherwise they flew erratic routes between the raised road surface and the lower border of the low dense scrub with numerous scattered spruces that covered the lower part of the valley, with the treeline occuring c. 100 feet higher up the valley slope:
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