Based on 1,947 research-grade iNaturalist observations in Washington, California Tortoiseshell is most often recorded in July; in Washington it behaves like a summer visitor / breeder. It ranks #5 among butterflies recorded in the state in our data.
Nymphalis californica
California Tortoiseshell in Washington by month
Bars show research-grade observations per month. They mix true seasonality with how often people are outdoors, so treat small numbers with caution.
Also seen in Washington in July
Western Tiger Swallowtail
Lorquin's Admiral
Snowberry Checkerspot
Small White
Clodius Parnassian
Woodland Skipper
Edith's Checkerspot
Pacific Fritillary
Places to look in Washington
National ForestGifford Pinchot National Forest
National ForestOlympic National Forest
State ParkPeace Arch Park
National ForestColville National Forest
National ForestMount Baker–Snoqualmie National Forest
Botanical GardenBellevue Botanical Garden
FAQ
When does California Tortoiseshell appear in Washington?
Mainly June–September, with the most records in July.
How common is California Tortoiseshell in Washington?
It ranks #5 by number of iNaturalist observations among butterflies in Washington (1,947 records in our sample).