I just can’t help myself. The cooler weather of autumn already has me thinking of the depths of winter; one of my favorite times of year. Here’s something I wrote about 8 years ago. This pond, especially when it is iced over, is still one of my favorite places!
Biting cold temperatures and a gusting wind make this frozen beaver pond slightly less than hospitable. Layers of clothes keep most of me warm, but I must admit even my bearded face feels the sting of this frigid northwest wind. A dull sun tries to bleed through the high thin clouds but produces little warmth on the February afternoon. The ice, thick with deep cracks that straddle the length of this 20 acre beaver pond, stands rigid to my weight. Only a day ago I had a group of graduate students on this frozen pond to discuss winter beaver ecology. As we toured around the pond we kept an eye out for ice domes formed by warm springs that create circles of raised ice where the frozen water is thin. In general the group was not nervous, but I noticed a few weary eyes as we traversed the ice.
On this day I am back to experience the ice as it should be encountered: quiet and alone. The pond is overflowing with life during the warmer months; frogs croaking, damselflies whirring, herons flying overhead, geese honking, and beavers splashing their tail flat against the standing pool of water. Now, there is only the steady howl of this northwest wind.
The ice at the edge of the pond squeezes last years blades of tussock sedge and blue-joint grass. Knobs of fractured tree stumps poke through the flat, glazed ice surface looking like a sea of headstones in a lost cemetery. As I venture further out in the direction of the main beaver lodge I stop by several of these skeletal remains of trees long ravaged by still, flooding waters. Curiously, the ice around the base of each stump is almost perfectly clear. You can get a sense of the ice depth by getting on your hands and knees and looking through the bubbles trapped in ice along the stump’s shaft. Green lichen clings to the smooth surface of the stump trapped in the frozen water, somehow appearing like a scene in one of those snow globes that tourists purchase after visiting a ski lodge.
As I approach the main beaver lodge I can see where coyotes have left their tracks in the snow. There are two sets of prints, both fairly small. This is likely an indicator of two young wild canines. It appears that they tried to dig at the surface of the lodge and gave up quickly when they realized the sticks and mud cemented by the ice was impenetrable. The tracks wander off to the northwest in the direction of a wooded swamp where hunting has far better possibilities.
The top of the lodge is littered with new debris; sticks with freshly removed bark indicating the lodge is still active. From this vantage point I can see three other, smaller, lodges. This was surprising to discover yesterday with my grad students. Each lodge also has sign that indicate there are beavers utilizing the area. The pond seems far too small for four pairs of beavers but evidently it is not. Ample winter forage is the main indicator as to how many beaver a pond can support. If there is inadequate forage the older beavers will drive off some of their previous years’ offspring.
This pond is absolutely covered with water lilies in the summer. Although white water lilies dominate, there are significant areas of yellow water lilies gracing the water’s surface. The lilies form a complete mat over the water’s surface in these warmer months making it appear as if there is almost no water at all. This pond is ten feet deep at its deepest location. The pond has a broad perimeter of emergent vegetation; broad and narrow leaf cattails to the east, tussock sedge, wool-grass, dark-green bulrush, blue-joint grass, and fowl meadow grass to the north, south, and east. These broad emergent wetlands surrounding the beaver pond cover an additional ten acres bringing the total size of this beaver created paradise to nearly 30 acres.
As I stand on the ice next to the main lodge I think about its’ inhabitants. Secluded to a dark world of cold water under ice and the chamber in the lodge for a duration of about about five months I imagine when Spring does arrive the beavers are immensely happy. Winter is principally a time of rest for beaver. Each day they exit the lodge through the underwater entrance hole and deposit some of the now naked twig forage from which bark and cambium were consumed the day before. They may swim around the underwater environs for a short while to get a little exercise. Before re-entering the lodge they will gather up some more of the branches that were placed in a cache near the lodge entrance and bring the forage back into the lodge for more nourishment. Knowing how busy they are during the warmer months I wonder if they actually appreciate this “resting” period. In any case I am sure that as the sun rises higher on the southern horizon and the days get longer and yield higher temperatures the beavers appreciate the thinning ice as the vernal equinox approaches.
I walk over to the heron nests. There are now four. Only a few dead snags remain in open water where the heron’s feel most comfortable. This has limited the heron rookery to just four pairs, down from seven only a few years ago. There is one primary nest that is about four feet in diameter. The other nests, located in less suitable locations, range from two feet to thirty inches in diameter. The habitat, although limited by the nesting few nesting sites, is rife with forage. The herons have more than ample food supply in this pond. Not only is the pond inhabited by pickerel, perch, sunfish, and small brook trout, it has a plethora of bullfrogs, green-back frogs, and pickerel frogs. It is prime forage habitat for the herons that utilize this refuge; all made possible by the tenacity and creativity of the resident beavers.
Near the dam I can see two sets of large parallel tracks that travel along the ice on the downstream of the dam. There are long snow smears where the river otter slides across the ice and into the water. This cheerful predator does not rely on dormancy to survive the long winter; rather it relies on boundless energy and superior hunting skills to help keep its belly full. I have witnessed these prolific hunters up and down this entire watershed in both winter and summer. They are a bundle of non-stop motion and activity. Although they appear to enjoy life, and even seem to be clownish by nature, they are for the most part fierce predators determined to survive another day.
As I approach the other side of the beaver pond I enter a hemlock swamp. It is dark; covered with layers and layers of thick evergreen boughs overhead. What little light there is reveals an acre or so of low to medium height hummocks; long lost wind thrown trees decaying slowly in this wetland. On each hummock there is a new tree. The ones near an opening in the canopy have grown more quickly, reaching for the sky like a bystander at a stage coach robbery.
I turn to look back at the beaver pond. The wind is quieting down with the end of day. As dusk begins to shroud this ice covered world the howl of a distant coyote can be heard to the northwest.
Another cold night will create a frozen memory of survival for those that live in this cold world.