Did that butterfly follow me home?

Each year, as the warm weather finally reaches our part of the world, Pacific Science Center’s life sciences department receives a few frantic phone calls from recent guests, sounding something like this:

“Hi. I visited your wonderful butterfly house two days ago. I must have had a butterfly sneak home on me, because this morning I saw it flying around my yard. I know you follow strict containment laws, and I want to get it back, but I couldn’t catch it. What should I do?”

Recently, as the public becomes more aware of the threats posed by invasive species, these calls have become more common. Many callers have not visited us recently, but simply have concerns about unfamiliar insects found in their areas. We always welcome these calls, and encourage our readers to be watchful for new and unusual looking insects. Often an informed public is the first line of defense against invasive insects.

But to those diligent and caring souls who have concerns about butterflies in their yard, you may find this reassuring. If your butterfly looks like this,
you need not fear. The Western Tiger Swallowtail, Papilio rutulus is native to Washington State. Its caterpillars feed on many native trees. The adult butterfly is active from late spring through the beginning of cold weather in the fall, and is often spotted nectaring in gardens.


The Polyphemus moth, Antheraea polyphemus, another native species, is mostly nocturnal. Although not rare, the Polyphemus moth is surprisingly good at hiding during the day. Callers who spot these large, handsome moths often report that they have lived in the region for many years and never seen one before. Many assume that nothing so striking could possibly be native to our region, which is not known for spectacular bugs.


In addition to these two Lepidoptera, our area is home to the large and magnificent ten-lined June beetle, Polyphylla decemlineata. Despite their name, these colorfully marked beetles usually arrive in July or even August in our area. They are known for flying to porch lights at night, and for hissing when startled – often frightening their captor.

We hope that a visit to the Tropical Butterfly House and Insect Village will only enhance your appreciation for our native species, large and small. And while we always welcome calls about butterflies and other insects, we hope that when you see these species, you will enjoy them without guilt, knowing that they are where they belong.


Photographs of the Western Tiger Swallowtail and the Polyphemus moth are in the public domain. The ten-lined June beetle was on Brianna’s porch.