Thursday, August 23, 2012

Thursday Flutterby: Willows, dead leaves & hail

Migrating Yellow Warbler playing peekaboo in willow
The first sign of the coming Fall in the Home Bug Garden is usually some yellow in the trees. Around the middle of August, year after year, small yellow warblers start to flit around the willow, apple, and lilac growing around the pond and bird bath. Mostly these are Yellow Warblers (Setophaga petechia). At our place in the country, where water and willows abound, Yellow Warblers are present throughout the summer. At the city-mired Home Bug Garden, though, we only see them in transit, the first of the wave of southbound migrants and a reminder of yellow leaves to come.
Green Comma Polygonia faunus - a harbinger of dead leaves to come
Another willow aficionado also showed in mid-August this year: the Green Comma (aka Faun Anglewing) Polygonia faunus. The 'green' seems to refer to the narrow lichen-green marks near the margin of the underside of the hind wing (barely visible in the picture above). I think this is  male and perhaps hopeful that a agreeable female may also find the willow attractive. But if so, he will have a long wait - until next spring. In a month or so, he will have to find a place to hibernate amongst the fallen leaves. Meanwhile he enjoys the sun, when it shines, and whatever tasty bits of ooze he can find (these butterflies are not much interested in flowers).
The upper, much more lively side of the Green Comma
I'm pretty sure this butterfly is a Green Comma, that is I have talked myself into the identification and don't expect to be embarrassed by a real lepidopterist. But the Commas (from the silvery smile on the underside of the back wing) or Anglewings (from the jagged wing edges) are a difficult group with a number of very similar species in Alberta. For example, the Satyr Comma below.
Satyr Comma Polygonia satyrus near a nettle patch in the country.
The differences between the two species are subtle, but I have great confidence in this identification because specialists who actually work on the Satyr Comma agree with me. Its dead-leaf costume mixes into the gravel much better than on a green willow,  but shows its close relationship to the green Comma, as does its slurping up ooze
Satyr Comma with prominent comma and no green flecks
Although they may look alike, and act alike, these two butterflies function very differently as larvae. Caterpillars of the Green Comma feed on trees, especially birch, alder, and willow. The Home Bug Garden has birch and willow. The Satyr Comma's larvae, however, feed mostly on Stinging Nettle.  We tried nettle, but it is too painful for a home garden; however, they are supposed to also like hops, of which we have a bit. The hops is looking a little seedy after this afternoon's hailstorm, but perhaps next year a Satyr Comma will give it a go.
Hail storm - a spring, summer, fall aspect of the Home Bug Garden

1 comment:

  1. We have the yellow warblers all summer as well. Beautiful to watch. My mother always calls them yellow canaries and at 92 I guess she can call them whatever she wants!