It’s been cold recently, with high temps below freezing for almost a week; it snowed overnight too so I came out to take some pictures. But the sun was already melting everything and I got only this one (and my shoe print!):
What I did find to photograph though, were these amazing ice “chimneys” on the pond:
They apparently formed because the initial ice layer over the pond covered where the bubbler goes (or maybe the bubbler moved), so the remaining hole in the ice was filled with bubbly water; the bubbles froze in the cold air, forcing more bubbles to rise up and slowly creating a tube of ice with the bubbles climbing all the way to the top (if you look at the full-size picture you can see the bubbles at the top).
I broke the chimneys off, to clear some ice from the pond; here is an inside view of the ice chimney/tube:
And here’s a picture of Koko, enjoying the weather (when he wasn’t eating snow!):
M&I / GBMINI 
Next morning, the ice chimney is back – I’ll have to figure a way to stop it growing (concerned it will block completely when the really cold weather arrives!)