Small, fragile transplants from Oregon seem to have made a permanent home in the Tri-Cities.

For the second summer in a row, pine white butterflies appeared in Tri-City conifers during the last week of August. At least one butterfly expert said their repeat showing was a significant biological event -- the settling of a new species in the area.

The pine white butterfly -- neophasia menapia menapia -- amazed friends of small, fluttering things when it showed up around here last summer. The small, bright-white insect with black-lined wings had not been seen here, said James Dillman of Richland.

He is the curator of the biological collection at Washington State University Tri-Cities.

Dillman and other lepidopterists -- butterfly researchers and collectors -- came up with a theory about the Pine Whites' arrival.

They figured the butterflies, which can only live in western pine tree forests, were sucked up into the air by thermal drafts in the Blue Mountains near Baker City, Ore., drifted northward on a stream of air and finally were dumped in the Tri-Cities.

They partially assumed this because the butterflies were seen in abundant numbers around Baker City just before they appeared here, Dillman said.

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