Uncovering the Willow Tit (Poecile montanus): The Expert Excavator

Identification: A Tricky ID

Identifying the Willow Tit relies on a combination of subtle visual cues, habitat, and, most importantly, its distinct vocalizations.

Plumage Details

The Willow Tit has a generally duller appearance than the Marsh Tit. Its cap is a sooty or brownish-black, lacking the distinct gloss of a Marsh Tit's cap. The bib under the chin is typically larger and more diffuse. Cheeks are whitish but can appear duskier. A key feature, often visible in good light, is a pale whitish panel on the closed wing, formed by the pale edges of the secondary feathers; this is absent or much less obvious in Marsh Tits. The upperparts are greyish-brown, and underparts are off-white to buff.

Male, Female, and Juvenile Differences

Males and females are virtually indistinguishable in the field. Juveniles are very similar to adults, perhaps with slightly buffer tones and a less defined cap and bib.

Size and Build

• Length: Approximately 11.5-12 cm (4.5 inches).
• Wingspan: Around 17-21 cm (6.7-8.3 inches).
• Weight: About 10-15 grams (0.35-0.53 oz).

It often appears slightly larger-headed or more 'bull-necked' than a Marsh Tit, with a slightly longer tail.

Willow Tit vs. Marsh Tit (Poecile palustris)

Separating the Willow Tit from the Marsh tit is a classic birding challenge. Vocalization is the most reliable method, but a combination of visual clues can also help.

Willow Tit

• Cap: Sooty black and dull, often looking 'fluffy'.
• Cheeks: Large and clean white.
• Bib: Larger with diffuse, untidy edges.
• Wing: Often shows a pale wing panel (can be subtle).
• Voice: Nasal, buzzing call "dzee-dzee-dzee". Song is a series of melancholic, fluting whistles.
• Nesting: Excavates its own nest cavity.

Marsh Tit

• Cap: Jet black and glossy with a neat look.
• Cheeks: Smaller, sometimes with a buffish wash.
• Bib: Smaller with sharply defined edges.
• Wing: More uniform brown, lacking a distinct pale panel.
• Voice: Explosive, sneezing call "pit-choo". Song is a rapid, repetitive "schip-schip-schip".
• Nesting: Uses an existing hole or cavity.

Habitat & Distribution

The Willow Tit is often found in younger, damper, or more scrubby woodland than the Marsh Tit.

Preferred Habitats

It favours damp deciduous or mixed woodlands, particularly areas with birch, alder, and willow. It thrives in younger successional woodland, scrubby areas, and conifer plantations with plentiful dead or decaying trees suitable for excavating nest holes. They are less common in mature, closed-canopy oak woodland preferred by Marsh Tits.

Geographic Range

The Willow Tit has a vast Palearctic distribution, found from Britain and Scandinavia across northern and central Europe, and through Siberia to Japan. Several subspecies exist. Populations are largely resident, staying on their territory year-round.

Distribution Map

The map below illustrates the vast resident range of the Willow Tit.

Behaviour: The Nest Digger

The Willow Tit is a territorial and resourceful bird, best known for its unique nesting habits.

A Territorial Bird

Willow Tits form stable pairs that defend a territory year-round. They are much less gregarious than other tits and are rarely seen in large flocks. In winter, a pair might join mixed-species flocks but often remains on the periphery. They are curious but wary birds, quick to disappear if disturbed.

Food Caching

Like the Coal Tit, the Willow Tit practices food caching. In late summer and autumn, it hides thousands of seeds and insects in bark crevices, under lichen, or in the ground. Its remarkable spatial memory allows it to retrieve a large portion of these caches during the difficult winter months.

Diet & Feeding Habits

The Willow Tit's diet comprises insects in summer and a mix of seeds and invertebrates in winter.

Primary Food Sources

During spring and summer, their diet is dominated by insects (especially caterpillars, aphids, flies) and spiders, crucial for feeding their young. They meticulously search branches and leaves for prey.

Autumn and Winter Diet

In autumn and winter, seeds of various trees (birch, alder) and herbaceous plants become important, supplemented by any available insects and spiders. They will visit garden bird feeders, particularly for sunflower hearts, peanuts, and suet, but are often more wary than other tits.

Nesting & Reproduction

The Willow Tit's dedication to excavating its own nest is its defining reproductive characteristic.

Nest Excavation

In spring, the pair selects a site in soft, rotting wood – typically a dead birch, alder, or willow stump. Both birds work to chisel out a deep chamber using their small beaks, carrying the wood chips far away to avoid attracting predators. This reliance on decaying wood makes them vulnerable to forestry practices that remove such habitat features.

Nest Construction and Eggs

Inside the cavity, the female builds a soft cup of moss, animal hair, and plant fibres. She lays a clutch of 6-9 glossy white eggs, finely speckled with reddish-brown. Incubation is by the female for about 13-15 days, during which she is fed by the male.

Raising the Chicks

Both parents feed the young with insects and spiders. The chicks fledge after about 17-19 days. Willow Tits usually raise a single brood per year.

Vocalisations: The Key to ID

The Willow Tit's calls and song are the most reliable way to separate it from the Marsh Tit.

Song

The song is a series of clear, rather melancholic, fluting whistles, typically on one pitch or slightly descending: "piu-piu-piu-piu". It's quite distinctive once learned.

Calls

The most characteristic call is a nasal, somewhat buzzy "chay-chay-chay" or "dzeh-dzeh-dzeh". A thinner, more drawn-out "eez-eez-eez" is also a common contact call. Hearing these calls is often the first and best clue to a Willow Tit's presence.

Conservation Status & Declines

The Willow Tit is facing alarming population declines across much of its European range.

Current Status

While globally classified as "Least Concern" by IUCN due to its vast range, the Willow Tit is a species of high conservation concern in many countries. In the UK, for instance, it is on the Red List due to a catastrophic decline of over 90% since the 1970s, making it one of the UK's fastest-declining resident birds.

Threats

The reasons for these declines are complex, but are strongly linked to habitat change:

• Habitat Loss: Loss of damp, scrubby woodland and the drainage of wet areas.
• Lack of Nesting Sites: The removal of dead and decaying trees ('snags') from woodlands and parks.
• Woodland Maturation: A lack of young, successional woodland and the loss of dense understorey as forests mature.
• Increased Predation: Higher populations of predators like Great Spotted Woodpeckers may play a role.

How to Help Willow Tits

Helping this species is primarily about habitat preservation:

• Conserve Dead Wood: In woodlands and parks, leaving non-hazardous dead trees and stumps standing is the single most important action.
• Promote Mixed Woodlands: Encourage forest management that maintains a diversity of tree species and ages, especially softwoods like birch and willow.
• Specialist Nest Boxes: Willow Tits rarely use standard nest boxes. However, special boxes filled with compacted sawdust can sometimes encourage them to excavate, simulating a rotten trunk.
• Winter Support: Providing feeders with sunflower hearts and suet can help local populations through hard times, although this does not solve the core issue of nesting habitat loss.

Frequently Asked Questions about the Willow Tit