We must be well off for woodpeckers around here as we've seen them quite often.
They can be difficult to spot in woodland even when you hear one quite clearly as though it's in the next tree but one. We have been visited by lesser spotted several times feeding on the nuts we hang up in the garden and once we saw three greens on the rim of our pond at the same time. I managed to get a photograph of the three of them but I can't trace it - I think it may have been before I got a digital camera as it doesn't seem to be on the computer where I download them all these days.
Columba - Did you run on the inside lane? That's forbidden for training on our local track so if it's the same at yours that could account for the Garmin discrepancy. I haven't calculated it but it sounds about the right difference to me. You'd expect the inside lane to be the measured distance.