Exploring Kootenay Lake

Common is a part of the name of many species: Common Carp (fish), Common Loon (bird), Common Pika (mammal), Common Whitetail (insect), Common Harebell (plant), Common Orange Lichen (lichen). Vastly more examples could be offered.

There are perils in incorporating the often misleading Common in a name. The species may have been common when named but uncommon now, or it may have been common in one region but uncommon in another. (We never see the Common Kingfisher around here, only the Belted Kingfisher.)

Last Thursday, when butterfly hunting with Janice Arndt (butterfly symposium), I watched a distinctly uncommon Common. Indeed, it is sufficiently rare that it is on the provincial Blue List—it is a species at risk.

Below are four pictures of this oddly named rare butterfly: the Common Checkered Skipper.

I enjoy polysemes—words with plural meanings. One might think that my title, butterfly symposium, must refer to a seminar of lepidopterists. It doesn’t. The root meaning of symposium is drinking party (sym: together; posium: to drink). Certainly, it is clear how the impression of reflective discourse arose from such a bibulous activity.

I typically see butterflies in ones and twos, but on this occasion I tagged along with Janice Arndt on her rare-butterfly project for the Waneta Terrestrial Compensation Program. There will be more postings from this jaunt as various butterflies are identified.

So, these butterflies are holding a symposium: they are drinking together. Chuckle.

Indeed, butterflies often gather at moist areas to sip water laden with salt and nutrients (as distinct from alcohol). These are things they don’t get from nectar.

The butterflies in these pictures are Tiger Swallowtails. The white and black ones are Pale Tiger Swallowtails, while the yellow and black ones are Western Tiger Swallowtails. These are rather large, impressive, and fairly common butterflies.

Pale Tiger Swallowtail Butterflies hold a symposium.

This Western Tiger Swallowtail Butterflies is drinking on its own.

As is this one. You can see the butterfly’s proboscis (its tongue) extending to the moist surface.

Two Pales drink together. There is yellow pollen stuck to an abdomen and to the left, a Western Spring Azure.

The two species regularly go drinking together.

“I’m arriving a bit late; may I join you?”

A pond skater goes by an amazingly large number of common names. Wikipedia lists some—water strider, water bug, magic bug, pond skater, skater, skimmer, water scooter, water skater, water skeeter, water skimmer, water skipper, water spider, Jesus bug—but, there are even more that those. Such a proliferation implies that the bug, itself, must be remarkable.  And it is: it walks on water.

The skater makes use of the surface tension of water for support by distributing its weight across long hydrophobic legs. From its maneuverable position on the surface of the water, it can detect, hunt down, and consume less fortunate invertebrates that have fallen onto the water and have become trapped by that same surface tension.

I watched a pond skater (Limnoporus notabilis) that initially seemed to be aimlessly standing on the water’s surface. Yet, it was busy. Its two front legs were feeling the water for ripples produced by anything trapped by, and struggling against, the surface tension. The ripples carry information about the bug’s direction, distance and size. The skater sensed something and abruptly headed straight towards another bug about four meters away and undoubtedly beyond its visual acuity.

The skater quickly closed in on a female robber fly (Nicocles sp.). After all, the skater is highly mobile on the water’s surface and the fly is not.

The skater punctured the robber fly’s abdomen and began to suck its juices. The fly now struggled against both the water’s surface tension and the actions of the skater. It thrashed about vigorously, but the outcome was foregone. There was no escape; this is how the skater makes its living and it is good at it.