We've been without a song thrush in the garden all winter. There were a few thrushes down the road, but none came along to our feeders, even in the worst of the weather. Thrushes have now begun to reappear in increasing numbers, and this chap started to sing from vantage points around our house. His favourite place is the fir tree opposite, not the very top but slightly down from it. This may be because the topmost twigs are already heavily used by smaller birds passing through.
The British Garden Birds website, here, confirms what we have noticed: some thrushes in more northern parts of Britain migrate south for the winter, while others stay and may be joined by migrants from colder places like Scandinavia.
At the moment our thrush seems to sing almost ceaselessly from first light through until dark, and it's a mystery when he manages to find time to snatch a meal. Presumably all this effort is aimed at attracting a mate.