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A brief announcement before discussing today’s subject: this blog will be on hiatus for a couple of weeks. We’re taking our annual vacation (at last!). Of course, I’m taking my cameras with me and it’s my hope that I’ll have some very neat images to post on my return. I should resume posting on September 19.
As their name implies, Giant Swallowtails are very large butterflies. With wingspans of three inches or more, these big swallowtails are the largest butterflies that we see in the Tucson area. They are immediately distinguishable from other swallowtail species with similarly colored and patterned wings because Giant Swallowtails have all-yellow bodies. No other swallowtail species does.
These butterflies are a pretty common sight in the Tucson area each late summer and autumn. I photographed this individual in our backyard the other day. It was among at least four swallowtails that visited our yard in a one-hour period.
Giant Swallowtails are one of those species that appear to have benefitted from human activity. This species originally had a range that was limited to the southwestern United States. However, it is expanding its range gradually, possibly due to climate change.
The caterpillars of these butterflies love to feed on the leaves of citrus trees. For that reason, citrus growers consider them to be a nuisance despite the adults’ obvious beauty. There are no commercial citrus groves that I’m aware of in Tucson or its immediate suburbs. But, local residents love to plant citrus in their yards and thus, there is plenty of forage for the caterpillars. The commercial citrus growers have my sympathies but, personally, I love to see these insects.
There was a severe freeze in Tucson one January morning a few years ago. Native plants shrugged it off for the most part, but a lot of those non-native citrus trees suffered freeze damage. Some trees were killed outright and others suffered severe limb die back from freezing. For a year or two thereafter the Giant Swallowtail population appeared to be greatly diminished. Most of the citrus appears to have recovered and these big butterflies are once again a common sight.
Images made with a Canon 5Div, 100-400mm ISII zoom lens, aperture priority setting, ISO 1000, first and third image shot at f5.6 @ 1/4000, second image shot at f5.6 @ 1/6400.