Mistle Thrush

Defends Yew berry crops aggressively in winter, chasing off Blackbirds and Fieldfares. A textbook example of resource-defense behaviour (Snow & Snow 1988). The Yew aril is consumed whole while the toxic seed passes unharmed.

Also defends Rowan berry crops in upland areas using the same resource-defense strategy; a key disperser of Rowan seeds into open habitats above the treeline.

Primary ornithochorous disperser; sticky seeds are wiped from the bill onto host branches after ingestion. The namesake mutualism from which the bird's English name derives (Snow & Snow 1988).