by KTNA Staff ~ April 23rd, 2012
Photos by Robin Song
On this week’s Earth and Beyond program, host and producer Robin Song relives springtime treks as snow melts, birds migrate, and waterways break up. We hear about a visit of a large flock of snow buntings, waterfowl, hatching aquatic insects, moose remains, ravens, and more. Audio runs 7 min 45 sec. Text follows.
A springtime snowstorm on April 6th brought a flock of 44 Snow Buntings to Birch Creek Ranch. That topped the count of 32 Snow Buntings, which had come to the ranch in late March. They had stayed about a week, leaving on March 30th. Six buntings had remained, but the storm brought the flock back, plus a few more of their friends. On April 7th I awoke to find only three buntings on the greenhouse frame behind the barn. I knew the birds were continuing their northward migration. I strapped on snowshoes and examined the snow under the greenhouse frame, hoping to find a feather. They had done a lot of preening, while sitting on the metal poles of the frame, but no feathers graced the snow beneath.
I had seen a pair of Trumpeter Swans in the pond across from Fish Lake on April 9th, and a female Common Goldeneye was with them. Each time I drove in to Talkeetna, I looked for the swans, but that was my only sighting. On April 12th I decided to head out to the Big Su to look for open water and hopefully swans. I strapped on the snowshoes and headed along the trail used by fisherfolk, Lyra scampering over the firm crust. We came out on the bluff above the river and discovered a pair of Common Goldeneyes in the open channel below the bluff. There were three channels of open water, with the rest of the river still sealed under snow and ice. Ducks dotted the dark water, and I photographed Green-winged Teals, Mallards, and Goldeneyes. A couple of times ducks took to the air, circling over the river to land in a different stretch of open water. A pair of Common Mergansers flew by, heading up-river.
After about half an hour of duck-watching, I headed back along the bluff, my goal being Montana Creek. I was watching my footing when a feather caught my eye. Then another… and another. When I found a few wing and tail feathers, I recognized that they had belonged to a Snow Bunting. Though I had not found a feather from the flock at the ranch, I now had the opportunity to photograph and examine them. I thought it was an unlikely place to find bunting feathers, but when I looked closely at the snow on the river shore below the bluff, I saw many insects crawling on the snow, along with footprints of buntings. The snowbirds had come here to eat the insects, and some kind of predator had caught an unwary bird. I had watched the buntings at the ranch preening and had discovered that the lower half of their snow-white feathers are dark gray. This dark color is hidden by the white upper-half of the feathers and only shows when the bird is preening. No doubt the dark lower-half acts as insulation for the bird, holding its body heat in.
Later, making my way along the south shoreline of Montana Creek, I photographed one of the insects, to look it up later in my “Insects of South-Central Alaska” book. Thus I learned that these insects are called “Stoneflies”. The adults have antennae at least half as long as their soft bodies. They are mostly nocturnal, and hide during the day under stones or in vegetation. I had observed many of the stoneflies crawling into the ice, going down through the maze of large granules to hide. The nymphs are aquatic, and live in the fast currents of rivers or in higher-elevation cold lakes.
Some stonefly nymphs feed on salmon carcasses in the river and also become food for salmon fry. The presence of stonefly nymphs are an indication that a river is healthy, for they require clean, cool, well oxygenated water to live. There are eight families- including seventy-two species- of stoneflies in Alaska. The Snow Buntings time their arrival to the emergence of the adult stoneflies along the rivers in Alaska. These insects become an important food-source for migrating birds as they make their way north. I came away with a new respect for these humble insects which I have seen every spring, but didn’t know their true purpose.
I had heard several ravens calling from the cottonwoods near Montana Creek and I stood watching a first-year bird preening high up in a grand old cottonwood tree. Its beak gaped in between bouts of preening. It was sitting in full sunlight, and was now getting over-heated. After several months of experiencing no heat coming from the winter sun, this raven was basking in the warmth. The inside of its mouth was deep pink, which only exists during ravens’ first year, then turns dark gray. I noted something on the snow under the tree and walked over to investigate. Two balls of moose hair were sitting amongst a wide area of raven droppings. I pulled one gently apart, and discovered bone fragments inside. I know that owls do not eat carrion, so these pellets had to be from the ravens. It also indicated that there was a dead moose somewhere nearby, which would also explain the noisy chatter of the ravens.
I headed towards the railroad tracks, expecting to find remains from a moose-train encounter. I did not. I headed along in the forest and soon Lyra had stopped by a tall spruce. There, at its base, lay the remains of a yearling moose. It looked like it had gone to sleep beneath the spreading branches of the tree and had not awakened. I headed on south, and was surprised when Lyra discovered the remains of another yearling, this time lying by the base of a large birch tree. It looked like the twin to the other moose. I have heard an estimate that 90% of the yearling moose calves have died over this winter of deep snow. Sad to contemplate, but they also fed a lot of birds and animals which may have otherwise also been in trouble this winter. Nothing is wasted, in Nature.
As the temperature climbs and the snow melts faster, my snowshoe and ski treks will come to an end. I still have a little time, and will get out to explore as much as I can, to the delight of my canine companion. Though mud and rain puts a bit of a damper on the change of seasons, the return of the birds far outweighs the prospect of having to put away the snowshoes and skis for the year. On April 15th Al Kingsbury heard and saw the first robin at the ranch, and the next day I heard my first Ruby-crowned Kinglet. The male Dark-eyed Junco, which spent the winter at the ranch, is now singing his courting song, awaiting the arrival of the girls. Why he chose to spend the winter in Alaska is a mystery, but for sure he’ll surprise a few of the ladies when they return to the ranch after their long migration. He had an easy winter, eating the seeds I put out for the chickadees and redpolls. Maybe his gamble paid off, and he’ll decide to spend next winter here.
The corvids are off sitting on eggs, now, along with the owls. The winter flock of chickadees, redpolls and grosbeaks no longer come to the feeders. Woodpeckers are chasing each other amongst the trees. There are more woodpeckers and squirrels on the ranch than I have ever seen, and it makes for a lively time, what with squirrels scampering over the snow and woodpeckers sounding like squeaky-toys in the trees. The sap is rising and pussywillows are appearing. Have you caught “spring fever” yet?
April 17,2012 by Robin Song