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March 4th, 2004  White Spring Last week I officially wrote winter off. It would follow that next I would welcome spring, but it’s not the spring most people imagine when spring is mentioned. Here in 100 Mile House, where we live at an elevation of 3000 feet, spring can best be envisioned in three distinct portions. In March we get white spring. April brings brown spring - a whole month without snow, a time when the landscape is dead brown grass with nothing growing. In May we finally see colour appear so it might be termed green spring. During white spring, snow can still fall in copious amounts, and temperatures can still drop to minus 20 Celsius. I refer to the snow squall events as set-back days because after watching patches of brown grass slowly emerge from under the snow it was troubling to see them covered again. There is a bright side at this time of year though, the sun is higher in the sky and any snow accumulations often melt before the next flurries arrive. It is during white spring that the large migration of Varied Thrushes begins. So sure am I that this event will start on time I deliberately sat out on the porch step on the 29th of February awaiting the first Thrush - and I was not disappointed. I only had to wait about 5 minutes when, without fanfare, I saw a familiar dark bird fly across the road to an open patch of brown grass under a fir tree. Instantly I knew it was a Varied Thrush. “Welcome back,” I said quietly to the Thrush as it began to poke about for food. Just then a car came up the driveway and the Thrush vanished. A while later I saw the unmistakable profile of another Varied Thrush silhouetted against the sky, high in a lodgepole pine, its bill thrust skyward. White spring had begun right on cue. From now on the numbers of Varied Thrush will grow as wave after wave of these stout, hardy birds make their way north. Some will stay to nest in our area but many more will press on to places as far north as Alaska. As one can imagine, being among the first birds to venture north can be a risky business. I do my part to offer them food as they pass through my yard and have found they will readily eat ‘flatted corn’ and chopped up apple. Male Robins begin flowing into our area about the same time as the Varied Thrushes and they too will eat both of these food items. Left to their own devices Varied Thrushes search snow-free ground for edibles. I don’t really know what they find to eat but I assume it might be things as diverse as the seeds of evergreens, leaf mold, rootlets, or insects lying dormant in the earth. A Varied thrush that stays around for a while will repeatedly return to a divot it has dug in the hard earth. After a few days these holes can become rather expansive and I imagine its not always the same bird returning to resume work but likely another Varied thrush familiar with this food hunting strategy. I spill bits of chopped suet and flatted corn into the divots in the birds’ absence, a bit like salting a mine. In past white springs I have counted as many as 35 Varied Thrush in the yard at one time but I have also seen bad years with only 3 Varied Thrush in total. I assume these birds - as are other species - will be subject to the vagaries of weather and nesting success so their numbers would fluctuate somewhat from year to year. It is always heartening to see a good return and I await the big numbers again this year. Tail-less Mountain On February 17th I noticed that one of the Mountain Chickadees coming to my seed feeder had lost its entire tail. How could something like this happen? Right away I imagine that the feathery appendage was lost in a close call with a predator but I’m sure there may be other explanations that aren’t quite so dramatic. I have seen photographs of birds that inadvertently got crushed between two swaying branches so its possible that the Mountain Chickadee lost its tail in a similar manner. Regardless, there it was an already small bird made even smaller by the loss of one third of its length. I wrote the date I saw the tail-less bird on the calendar so I could watch how long it took to this bird to regrow a new tail, if indeed that was what would happen. Normally birds lose and replace all their feathers during the course of a year but the loss of important feathers like those of the wings and tail are done in stages. Birds like Chickadees usually molt a few outer tail feathers on each side of the tail and are left with a few central feathers that still give the bird necessary flight capabilities. So what happens when the whole tail is lost? The bird can still fly but would it have to wait until a regular molt to get back a new tail? I didn’t think so. There must be a special mechanism in place that recognizes the predicament and gets busy growing the whole set of feathers at once. In the following days I watched the tail-less Chickadee chased from the seed feeder by those of its own kind. I guess looking different was causing it undue attention. For at least ten days I saw no signs of a new tail growing. On February 29th I saw the tail-less Chickadee for the first time in a number of days. From out between its undertail and overtail coverts a small fan of gray tail feathers was visible. I estimated the length of the emerging tail to be about one-third the length of a full sized Chickadee tail. Today, March 3rd, I saw the bird again and estimated that the tail was now one half its potential length. Soon I imagine I won’t be able to pick the once tail-less Chickadee out of a crowd. In 16 days it has grown half a tail so I guess in another week it will be fully fledged again. 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