 The typical clutch is 6 – 11 eggs across most of the range , but appears to be smaller ( 5 – 8 ) in Kashmir at around 1 @,@ 500 m ( 4 @,@ 900 ft ) altitude . Laying dates vary with location , from late March in western Europe and North Africa , to late May in Kashmir and June in Iceland . The clutch size may be smaller early or late in the breeding season . The breeding season can be extended by replacement and second clutches . The eggs are blunt and oval , smooth and slightly glossy ; the colour varies from off @-@ white to pink @-@ buff , with reddish @-@ brown blotches mainly at the broader end that sometimes merging into a single patch . Variation in egg size across the four subspecies is much less than differences between individual eggs ; the average size of the eggs of the nominate subspecies , 36 mm × 26 mm ( 1 @.@ 4 in × 1 @.@ 0 in ) , is therefore typical for the species as a whole . The eggs weigh about 13 g ( 0 @.@ 46 oz ) , of which 7 % is shell . 
