Long-tailed tits live in family flocks through winter and their welfare depends on maintaining group cohesion and access to insect food.
Long-tailed tits roosting communally in cold weather directly improve each other's thermal welfare. Birds separated from their flock face both cold exposure risk and reduced foraging efficiency from loss of social information about food sites. Maintaining winter insect food availability through reduced pesticide use and garden supplementary food benefits flock welfare.