Have any of you seen evidence that Ruffed Grouse actually burrow in the

I have just started reading *Winter World* by Bernd Heinrich. In his chapter
on snow and subnivian space he claims that Grouse and other birds actually
burrow under the snow: -- " in the Maine woods I routinely find over thirty
fecal pellets (in these snow shelters) where a ruffed grouse has spent the
night. Often these birds also stay the day in their shelter, because on
snowy, cold days I have flushed them out from underfoot under the snow even
at noon."

I have seen snow accumulate on birds, but I had never heard of them
burrowing in it.

Your thoughts or observations?

Moretown Village