Ann Arbor Weather:
Saturday October 16, 2021
Follow us: facebook twitter RSS feed
Swallowtail butterfly

The Biggest Butterfly

Seeking giant swallowtails

by Bob & Jorja Feldman

From the August, 2015 issue

Sometimes we have to sharpen our observational skills to see what is going on outside. However, one very large butterfly is easy to spot. The aptly named giant swallowtail is the biggest butterfly in Michigan.

Form your two index fingers into pointers and touch them to each other: if you take a large glove size, the butterfly's maximum wingspan is approximately the length of both fingers put together. The field guides say around six inches.

The giant swallowtail's coloration is as spectacular as its size. From the top, its wings look dark brown to black, with yellow dot ribboning and a yellow eye-shaped spot on the end of each wing. When the wings are raised, the bottom is revealed to be a subtle cream interrupted by wavy blue and rust bands.

Ronda Spink, coordinator of the Michigan Butterfly Network (, says she sees more and more of these butterflies each year. This species spends its Michigan winter in the pupa stage and emerges in two broods each summer, the first in May through June, the second in July through early September.

Once you have seen a giant swallowtail live and in person, you will remember it forever. The best time of day, according to Spink, is usually from around 11 a.m. to 4 p.m.; we suggest choosing bright, warm days. Watch for these beauties flying at about eye level and moving at a leisurely pace (for a butterfly). You won't have any doubts once you see one; no other butterfly around here looks anything like it.

In Ann Arbor, they can be found in both cultivated gardens and natural areas. In private gardens, butterfly-friendly plantings include purple coneflowers and butterfly bushes. You may also see one in Matthaei's Gateway Garden and in the Rotarians' butterfly garden near the Gallup Park canoe livery.

Becky Gajewski, stewardship specialist for the city's natural area preservation unit, says that among the parks and natural areas that have been surveyed, volunteers have seen giant swallowtails most often at Bandemer, Barton, Furstenberg, Marshall, and Mary Beth Doyle. All of these nature areas (as well as several more) have prickly ash or wafer ash, the larval host plants for the giant swallowtail.

Mother Nature gives no guarantees, so we cannot say for sure that you will see a giant swallowtail this season. But even if you don't, a butterfly hunt is a great excuse to get outdoors this summer.     (end of article)

[Originally published in August, 2015.]


Bookmark and Share
Print Comment E-mail

You might also like:

Burns Park Butterflies
Lynda Asher is raising monarchs.
Cynthia Furlong Reynolds
Today's Events
Testing the Waters
How Lea Monaghan and her colleagues keep the city's drinking water safe.
Ken Garber
Subscribe to the Ann Arbor Observer
Health Care - Mental Health: Treatment
Lectures, Readings, Discussions, & Forums
Afghans Arrive
JFS is on the case
Eve Silberman
Photo: Rosie the Riveter Turns 100
Nightspots: Mash
Crime Map
A clickable, zoomable map
SEMI e news
west end grill