[EBB Sightings] white crowned sparrows

I have noticed this week that the white crowned sparrows in my yard
are starting to come into their breeding plumage.  Before that time the
ratio
of immature plumage to mature plumage was around 4:1.  Every year
that seems to be consistent.  Do some males or females lose their breeding
colors or is the ratio of new birds that high every year?   I have seen the
same in Purple Finches.

Nat Weber
Moraga, CA