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Identification
The Willow Tit is so similar to the Marsh Tit that it wasn't recognised as a separate species until 1900. Unlike the Marsh Tit, it excavates its own nest hole so it needs a strong head and neck, as well as the soft timber which is found in damp woodland and willow carr.
This could explain why the Willow Tit looks thicker-necked than the similar Marsh Tit.
It also has a more untidy black bib and, usually, a pale panel in the wing.
Habitat
Breeds and winters in damp willow, birch and alder scrub and occasionally in conifers.
Behaviour
The Willow Tit is unusual amongst the tit family in that it excavates its own nest from the rotting stumps of trees.
Migration
A resident and sedentary bird.
For more details click here