turns out this anthill is a well-known landmark on the Hoodoo trail...the ants have been building this pile of dry spruce needles for several years. being right near the arts centre, the hill has been featured in a number of videos etc. Hard to see them in these small photos...but trust me, the needles are completely covered in black & red patterned ants. they're quite nifty-looking ants, actually, and apparently they eat other more destructive insects, so i am trying to like them.
they didn't swarm out and attempt to drag us into the anthill when we walked by...so i conclude that they are friendly. or at least, indifferent. which is fine with me.