By David J. Hawke -- Those of us who seek out nature either for pleasure or for business are often hard-pressed to discover something new during the winter months. Migration and hibernation took most species away from view, and the few critters that remain visible become, after a time, "same old-same old". Maybe a new bird will show up at the feeder, but this season is nothing like the late spring-early summer overwhelming rush of blooming flowers and singing birds.
And so, after that preamble, you can share my surprise at finding a cabbage butterfly fluttering around inside our home in mid-January! A couple of moth species will seek refuge in a house for the winter months and may be found around the pantry or a clothes closet. But a butterfly? In January? Inside the house?
Here's a little background as to how butterflies generally get through the snowy season. Most of you will know that the monarch butterfly migrates, all the way to Mexico and then, via several generations, back to Ontario. Good for them. Gold standard. But a bit too much for the regular folk butterflies.
As for hibernation, yes, a few species do sleep through the winter as adults, the mourning cloak and tortoiseshell butterflies by example. Last fall the winged adults sought out cracks in tree bark or tiny crawl spaces under logs to bed down for the winter. Some will be discovered and eaten by mice and voles, but many will survive. By waking up in early spring these butterflies can lay their eggs on young twigs, thus allowing their soon-to-hatch offspring the benefit of tender new leaves to dine upon.
A few moth species will lay eggs in the fall and then die, perhaps knowing the next generation will carry on with gusto appetites for early season leaves. In this case I'm thinking tent caterpillars and gypsy moths. If any butterfly species do this technique their names escape me at the moment (hey, you got your homework assignment).
The vast majority of butterflies, and certainly many moths, dodge the freezing flowerless months by going into a state of suspended animation -- better known as a chrysalis or cocoon. Within this tiny do-it-yourself winter chalet the previously crawling caterpillar dissolves into a soup and reforms its cells as a flying insect, ready to pop out next spring or summer.
That's what cabbage butterflies are supposed to do, form an overwintering chrysalis, not fly around inside my home office in mid-January! Sharin' the excitement now, are we?
Cabbage butterflies are most often seen in late summer, sometimes in flocks of a dozen or more, fluttering in tight circles over field crops or small puddles. As there are over 20 species of butterflies within the group known as "sulphurs and whites" a close-up look is sometimes to needed to tell one from the other. Sulphur species tend to be yellow or orange, while whites are, well, white but with dark spots or lines. Sometimes you could find a white sulphur and sometimes a yellow white flies by, so this keeps one on the alert when traipsing through the meadows looking for Lepidoptera (fancy name for scaly winged insects like butterflies and moths).
The one in my room is a female Cabbage White, so determined by the black wing tips and paired black spots on the wings. And according to the ROM field guide "Butterflies of Ontario" (highly recommended) it is supposed to be inside a chrysalis right now. So, what happened?
Obviously, this is a mistake and nature is well-known for making mistakes. Sometimes a 'mistake' can lead to a new advantage previously unknown for that species. These 'leading edge' individuals may eventually set the stage for a whole behaviour pattern for their species... but usually they die trying. Some call this the Darwin effect as he theorized that stupid rebels get killed and thus, so too does that line of unusually wired genetics. However, if the change allows survival then that line of genetics gets passed along and within a few thousand generations a change will be noted in their behaviours or size or food.
Back to the little lady perched upon my light shade. I know that cabbage white butterfly caterpillars like to eat cabbage, broccoli and cauliflower, a trait that makes them rather unwelcome in a commercial crop field. Did this one in my room form a chrysalis within the head of a broccoli? Did the broccoli get harvested and was then sent to a cold storage room with the undetected hitch-hiker along for the ride? Did the warmth of the supermarket and then our home cause an acceleration of growth within the chrysalis? Did the butterfly emerge thinking it was spring and is now wondering "where is everybody, let's get this party started!"?
I may never know for sure as to why or how a female cabbage white butterfly came to be flying around the inside of our house in mid-January... the above is my scientific postulation... anybody excepting a spiritual reincarnation from across the void?
Dave’s notebook: Another January is behind us! Nature can sometimes give us a few surprises as this week's story shows us. You just never know when these things will come along.
© 2020 David J. Hawke