By Greg Lecker
The early bird finds the treats. Just after sunrise, walking around the north edge of Green Heron Pond, I follow two sets of tracks – one larger and one smaller.
Tracks in the Snow
I can identify the larger ones as Canid – probably coyote – based on size and the presence of claws. The size of coyote tracks would be somewhere between fox and wolf. It’s fairly assured that one can eliminate wolf from a metro-area wild Canid species (dog-like, similar to canine). The smaller tracks are a bit more difficult to identify. Rabbit and squirrel tracks are very similar – in size and in footprint shape. In the past, I have seen gray squirrel along this path; and I see that these tracks run off the trail towards trees. After a bit of research to verify my diagnosis, I conclude that these are gray squirrel tracks, rather than rabbit.
Coyote and Squirrel Tracks
Walking a bit farther, I find three black walnut shells that have been chewed open. Were these the treat that the squirrel had been hunting? The green hull has long been rotted away.
Black Walnut Shells
On my drive to the Arboretum, sunrise barely peeked through the only clear area of the sky – the ring around the horizon. As I enter the Wurtele Bog Boardwalk I’m happy to see that the lower clouds have moved on to reveal a spectacular array of altocumulus clouds.
Altocumulus Clouds at Sunrise
Altocumulus clouds are a mid-level formation – and that explains why these were hidden by the lower clouds that covered the sky at daybreak. Altocumulus can be identified by their globular massing or rolls in layers or patches. The individual elements of altocumulus are larger and darker than the somewhat similar cirrocumulus. Besides locating altocumulus clouds at between 6,600 and 20,000 feet; the source of the Wikipedia entry explains that “Altocumulus is commonly found between the warm and cold fronts in a depression, although this is often hidden by lower clouds.” I wonder if this is a confirmation of the large snow storm that is forecast for the day after Christmas.
The persistent cool weather has ensured that Green Heron Pond remains frozen over; and so too is most of the shallow water in the bog around the boardwalk. After a brief search, I do find a small patch of liquid water. Whether it is the movement of the heat of remaining decomposition that has kept this from freezing, I do not know.
Open Water – A Kaleidoscope
The curved ripples of surface tension surrounding the grass stems lend a kaleidoscopic design to this window into a miniature world. Snow and ice crystals add decoration.
As I walk back to the Oswald Visitor Center, I see that the low gray clouds have completely obscured the altocumulus clouds, the sun, and the blue sky I had enjoyed just thirty minutes earlier. Being this reminded how quickly our weather turns, I make a note to consult weather forecasts these next few days before making travel plans or at least before packing clothing.
I wish our readers warm and safe holidays with friends and family!
Greg Lecker is a Minnesota Master Naturalist Volunteer.