Winter is coming, frost and snow are a challenge to the birds that remain in the city. We can help them with some little expedient! " I was wondering where the ducks go when the Central Park lagoon got all icy and frozen?" This is what the hero of The Catcher in the Rye by Salinger, wonders about.
Forget letting birds nest in cute but unsafe birdhouses! If you really want to help wild birds, provide proper nesting boxes made for specific species and do what you can to prevent birds from using other hazardous nesting locations.