The crested tit is confined to Scottish Caledonian pine forests in the UK and is one of the most range-restricted woodland birds, with welfare dependent on ancient Scots pine forest.
Crested tit welfare is entirely dependent on the survival and expansion of ancient Caledonian pine forest. Loss of this habitat through historic felling has left the UK population isolated in a small area. Insufficient standing deadwood for nest excavation limits breeding density. Cold winters create food scarcity. The extremely restricted UK range means any local disaster could be catastrophic for the population.