A Bold Centipede

This 10cm long specimen of the centipede Stigmatogaster subterranea was patrolling around the top of a rock outside the kitchen window this morning. Surprisingly three hours later it was doing exactly the same thing on the next rock along and I assume it was there for the whole time. I've no idea what this behaviour was all about (possibly something similar to Martyn's observations of flies with Summits Disease - see http://goweros.blogspot.com/2011/08/summits-disease.html), but its scientific name suggests it should have been underground? More surprising was that the birds on the feeder, barely 1m away, showed no interest in this worm-like creature. [photos as encountered rather than set up]