Birds don't all make the same decisions. This seems trivial but can have mortal consequences. This Mistle Thrush has been basically living in the same tree for some time. It intends to stay for another month or two or until the berries are gone. It defends the bush from all comers, in particular other thrushes. It has made a decision and, as a result, is forced to endure the fact that it is an urban area. Humankind pass by close and cars too, honking their horns and such like. It must be stoic and stay put.
We heard about a different Mistle Thrush defending a berry bush in a similar situation. One day, the Sparrowhawk came along and killed it. The berries disappeared within two days from the Blackbirds.