Now that the snow has gone, there is evidence of serious damage to my lawn, right back to bare earth. Is this normal? Will it grow back without having to do anything? I'm not after Augusta greens, but in some areas it is a couple of square metres that is bare earth.

‘They’re everywhere!’ Pesky voles destroying Calgary lawns as they invade idyllic neighbourhoods | National Post

This is from 2014, my lawn is 10 times worse than these photos, no clue as to how to make the lawn better other than lay new turf ( or sods as they are known around these parts).

Scratch out the lumpy bits with a rake, fill any holes with a loamy top soil, scatter grass seed on bare soil and overseed other areas. Lightly rake new seeded area to mix seed with top soil and gently water. Make sure grass seed kept moist until grass established. Needs to be done once freezing temps are over and before gets too hot and dry.

That is precisely what I would do in uk, I suppose I was hoping that the grass would be so tough here, that it would grow back and that someone would say that. Sigh.....ill give it another week and do as suggested. TY.

It may come back on its own, just depends what you want it to look like.
http://www.calgary.ca/CSPS/Parks/Pag...s/Seeding.aspx