I have an L-shaped 20 x 9 ft run, and I kept it covered with bird netting (Lowe's $15 for 100 ft), but the first snow was so heavy, it pulled it all down. Since then my SLW has somehow been found on the OUTSIDE of the run (I have 3 SLW, 2 PBR and 2 BOs). I don't know if the same Wyandotte flew over twice, or if it was 2 of them on different days. Today I got my first eggs - 2 of them! I saw (and heard) one Wyandotte laying her first egg, and I think the other came from a Wyandotte too, but I didn't see it. Could they have been looking for another place to lay? Neither one of them used the nesting boxes - just nestled into the straw on the floor of the coop, under the hanging feeder.
My chicken wire is 5' tall - I wasn't expecting to find anyone on the outside. Not sure I want to put more netting up, because we've only had one significant snowfall so far, and there are still 3-4 months to go. Someone suggested clipping their wings - I'm undecided.
We're going to be hit with a bitter cold front in 2 days (-5 to -15), so I just put a light in the coop, but won't turn it on until the cold hits. So far they have done okay with a 5 degree night and no light/heat. I broke down and bought a heated waterer, and that was the BEST INVESTMENT EVER!