Marsh tits and willow tits are among Britain's most rapidly declining resident woodland birds; their welfare is threatened by habitat degradation and competition.
Willow tits and marsh tits in declining, fragmented woodlands face welfare challenges including reduced foraging success, competition-driven exclusion from optimal territories, and winter starvation risk in poor habitat. For willow tits specifically, the loss of rotten wood for nest excavation forces birds into suboptimal sites with higher nest failure rates. The welfare of individual birds in declining populations is directly linked to habitat quality - restoration of structurally complex, wet woodland with retained deadwood is the most effective welfare intervention.