Exploring Kootenay Lake

Winter is the time to see redpolls. These birds of the Arctic head south for the winter. They are named for their red polls (i.e., crowns, see previous posting), and seem to come in two species: Common Redpoll, Hoary Redpoll. Of the two, the most likely one to be seen around here is the Common (if it is even seen at all). However, a paler, less strongly banded Hoary, from the high Arctic, may occasionally be mixed among them.

However, recent research finds almost no genetic difference between these supposedly different species. Their variations seem to be less the result of genes as of gene expression. Do we care whether we are seeing differences between species or between gene expressions? It remains fun to see the regional variations as the occasional (high Arctic) Hoary appears among the Common.

The Common Redpoll shows strong banding on the sides.

The Hoary Redpoll shows weak banding on its sides. (Picture by Derek Kite.)

In the conventional scheme, the pale breast of the bird on the left would be considered a Hoary Redpoll.

This head-on view of a flying redpoll probably would be considered a Common. (Picture by Derek Kite.)

While this would likely be thought of as a Hoary Redpoll.

Derek Kite’s pictures are used with permission.

The House Finch is a common bird in the urban areas of southern Canada. Arising in the west, it has spread eastward. This is not a rare bird. 

Yet, it is more readily accepted than other interlopers, such as the European Starling and the House Sparrow, likely owing to the male’s lovely red colouring.

That red is not manufactured by the House Finch, itself, but comes from pigments in the food it eats during moulting: the more pigment, the redder the male. It seems that females prefer the reddest male they can find, perhaps because to do so increases the odds that their mate might be good at feeding nestlings.

“I am red and ready for love.”

The best place around the Lake to see hawks during the winter seems to be on the Creston Flats (at the south end of the Lake). On the West Arm, where I live, Red-tailed Hawks are seen, but usually a little later in the season, and the Rough-legged Hawk is really uncommon at any time. However, when seen around the Creston Flats, such hawks are only rarely close enough to allow for good pictures.

This Red-tailed Hawk is hunting from a tree.

While, this Rough-legged Hawk is hunting from the air.

The Sun came out; the birds came out; I came out — and took a distinctly odd picture. We are used to seeing folded wings on perched birds, and extended wings on flying birds. But, this shot shows folded wings on flying birds.

I was watching a flock of redpolls. They would alight on a bush, feed on seeds, and then abruptly take off all at once only to fly to an adjacent bush.

As do many small birds, redpolls use flap-bounding flight. Flight follows an undulatory path where birds flap through the troughs, and fold their wings to bound across the ridges where they follow a nearly ballistic trajectory. It is called bounding flight because it resembles the bounding gait of leaping earth-bound animals. Apparently such a flight pattern saves energy and allows birds to fly slower than their normal cruising speed. 

This view shows redpolls feeding on seeds before taking to the air once again.

As redpolls spend half their flight time flapping and half bounding (with folded wings), a typical view of them flying shows about half in each mode.

At one point, a distinctly odd image was captured where almost all were bounding. I suspect that there is a simple explanation. Birds take off together, and all start by flapping. Before they get out of synchronization, most will then begin bounding at the same time. A picture taken at that moment makes them look like a shoal of fish.

“Ok, I know that that obnoxious photographer (the one who tries to muscle in on my personal territory) recently made fun of my attempt to wander my domain in privacy. I was mortified by the insensitivity of his treatment. The truth is that I am a registered grouse model and have strutted on the world’s best avian runways. So, my agent has advised me to insist on better representation. As you can see, I am fully compliant with recent restrictions on ultra-thin models.”