A few weeks ago I spotted this handsome butterfly constantly circling and landing on our white metal railing. Even when I went out and stood next to the railing, the butterfly kept circling, landing for a moment, and then flying off to circle once more. If another butterfly of the same species flew by, he would chase the intruder off, often far over the roofs of our neighbours’ houses, only to return a minute later.
This butterfly is a Red Admirable (Vanessa atalanta), more often called the Red Admiral, although “Admiral” is really the name of a separate group of butterflies. Male Red Admirables are territorial; individuals will claim a particular site in a forest clearing or garden and patrol it, keeping watch for females and intruding males. Based on my butterfly’s behaviour, I think he’s likely a male, and he had claimed our railing and that section of our yard as his territory.
The Red Admirable lives in North America, Europe, and Asia; here in British Columbia, it is an easy butterfly to identify, as no other local species has its wings marked with a bold red band on a white background. The underside of the wings is much plainer, but this drab colouration helps the butterfly (when his wings are closed) to blend in with tree bark or leaf litter. The Red Admirable, like its relative, the Mourning Cloak, is a long-lived butterfly that hibernates over winter, a quality that I always find especially admirable.
At the Edge of the Ordinary 
I always called that type of butterfly a Red Admiral. I never knew they were a separate species!
“Red Admiral” and “Red Admirable” are both names used for the same species (Vanessa atalanta). However, there is a separate group of butterflies (subfamily Limenitidinae), which is often called the “Admirals”. (V. atalanta is part of subfamily Nymphalinae, which also includes the Mourning Cloak, Painted Lady, and the commas.) The common name “Red Admiral” can therefore be misleading – but that’s probably true of many common names. :)
Thanks for the info!