Winter World_ The Ingenuity of Animal Survival - Bernd Heinrich [18]
I dug the deer out of the snow and found hemorrhaging on the head and in the back of the neck; it had been alive when bitten. The wounds confirmed that a cat had killed this big, perhaps 140-pound, doe with a foot-long fetus inside her.
The raven flew by once more and called. I left then and detoured to check on a porcupine den in a pile of rocks in a dense spruce-fir thicket. Fresh tracks had gone in and out during the previous night. The porcupines were now eating the bark off red spruces and white pines, girdling the trees in huge bare patches of exposed trunk. They had long ago killed off their favorite food, hemlocks. Under one tree they had recently killed I found a regurgitated pellet, along with bird droppings near it. This pellet contained the long straight black guard hair and softer insulating hair of a bear, as well as a few balsam fir needles and a spruce cone bract. It was a raven’s pellet. Another winter kill might be nearby and so I immediately searched through the thicket, expecting the source of the pellet’s bear hair, but instead of a dead bear I found another dead deer. Both ravens and coyotes had just been feeding on it. No cat tracks here and this carcass was not buried by snow scraped over it. I stopped at the kill site, in my mind’s eye seeing the struggling of predators and prey, starvation and struggles in the snow, but hearing only the sweet songs of purple finches, pine siskins, and best of all the elfin song of a golden-crowned kinglet. The kinglet now buoyed my spirits as I enjoyed its sweet refrain and thought of the incredible endurance and luck that brought this bird through the winter, to finally have a hope of seeing spring.
As I made my way back to the cabin, I saw snow fleas collecting ever more by the thousands in the deep holes of the moose’s tracks; temperatures were now above freezing. A little spider walked on the snow, and then I found a rust-red furry Arctiid caterpillar humping along on the crust of the two-to three-foot-deep snow as well. Where was it going, and why, with not a green blade of grass in sight? (I took it home and reared it to the adult stage, and identified it as the ruby tiger moth, Phragmatobia fuliginosa.)
Finally as I returned to the cabin, there was no more doubt in my mind that most of the crossbills had left. Their nests had probably been destroyed in the recent, unusually heavy snowfalls. I should have known, since crossbills leave even their young in their nests if, in their boom-or-bust cycles, the food supply runs out (Macoun 1909). Only stray wanderers might remain, and as if to be reminded of that, one crossbill came in to camp.
A friend, Glenn Booma, a Winter Ecology student of 1990 who comes often to escape city life in Boston and who has proved his credentials by once trapping a water shrew, came to visit for supper. We lit a fire in the firepit to grill steaks, and as the smoke from the dried maple we had chain-sawed and split the previous fall rose into the early evening sky, a bright strawberry pink (adult) male white-winged crossbill flew in. He fluttered within a foot of my ear and then landed at the edge of the firepit. The crossbill hopped close to the glowing embers and picked at ash. Within another minute it departed as quickly as it had come, leaving us in surprise and wonder.
04
TRACKING A WEASEL
Scientific discoveries, like most surprises, come by luck, and luck comes by keeping moving and having a keen nose to detect anomalies. One may keep moving, to look for a crossbill’s nest, but, idiosyncratically, may find a raven’s winter food cache and much more instead. And that is also how weasels find and capture chipmunks in the winter woods, which I will get to shortly.
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