The marsh tit, a resident woodland bird, has declined by 80% since 1970 as coppiced woodland management has declined and deer browse has altered woodland structure across southern England.
Marsh tits in deer-browsed woodland find reduced invertebrate prey and reduced nest site availability. The loss of shrub structure removes the habitat complexity that supports the insects on which marsh tits depend. Winter food availability is particularly critical; marsh tits cache food and retrieve it in winter, requiring stable territories with adequate seed and invertebrate resources.