Willow tit / Weidenmeise (Poecile montanus)
Wikipedia Vogelwarte BirdLife ZH ornitho.ch bird-song.ch Xeno-Canto BirdID NABUWillow tit. 2020-04-25 08:51:40 Fehraltorf
Exposure 1/500
Observations
First documented observation: 2020-04-25 in Fehraltorf. Most recent observation: 2021-06-27 in Wildhaus.Description
Classification: Genus Poecile (Poecile); Family Titmice (Paridae)Vogelwarte.ch says, Two forms of Poecile montanus exist in Switzerland: the Willow Tit occurs in the Jura, the Pre-Alps and locally on the Central Plateau, while the Alpine Tit is confined to the Alps. The two forms have a distinct song as well as different ecological requirements, and could evolve into two species over time. Since I've heard them in St. Moritz, they're more properly alpine tits than willow tits. I should verify the audio recordings vs xenocanto, etc, as it was BirdNet that identified them as willow tits, and it is not infallible.
Vocalization:

Seasonal behavior
Year-round bird Breeding: 04-20 - 08-18
Other Details
Physical details
Physical details: length=11 cm, wingspan=17-20 cm, weight=8-14 gHabitats: Forest
Vocalisation
Song: Songs I've heard alternate two notes and look like a sine wave on the sonogram. Vogelwarte.ch: Apart from minor differences in diet and size, Alpine Tit and Willow Tit can only be identified by their song. The Willow Tit utters a series of long, descending notes («tyoo tyoo tyoo tyoo»), whereas the Alpine Tit’s territorial song consists of short notes on an even pitch («dee dee dee dee dee»). See more here. Vogelwarte.ch says, Two forms of Poecile montanus exist in Switzerland: the Willow Tit occurs in the Jura, the Pre-Alps and locally on the Central Plateau, while the Alpine Tit is confined to the Alps. The two forms have a distinct song as well as different ecological requirements, and could evolve into two species over time. Since I've heard them in St. Moritz, they're more properly alpine tits than willow tits. I should verify the audio recordings vs xenocanto, etc, as it was BirdNet that identified them as willow tits, and it is not infallible.Song:


♫ Source: OTHER 509229 (song)
Willow tit st moritz. Sils 2020-06-09 16:09:28
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Sils 2020-06-09 12:33:28 ♫ 2020-06-09 12:33:28 Source: BirdNet 20200609_123328 birdnet 599 - Willow tit.mp3 Sils (song?)
Sils 2020-06-09 16:06:43 ♫ 2020-06-09 16:06:43 Source: BirdNet 20200609_160643 birdnet 600 - Willow tit.mp3 Sils (song?)
Sils 2020-06-11 13:25:38 ♫ 2020-06-11 13:25:38 Source: BirdNet 20200611_132538 birdnet 614 - Willow tit.mp3 Sils (song?)
Sils 2020-06-11 13:26:11 ♫ 2020-06-11 13:26:11 Source: BirdNet 20200611_132611 birdnet 615 - Willow tit.mp3 Sils (song?)
Sils 2020-06-11 15:47:24 ♫ 2020-06-11 15:47:24 Source: BirdNet 20200611_154724 birdnet 621 - Willow tit.mp3 Sils (song?)
XC371134 Willow Tit song - rhenanus subspecis at Grünenbergpass, Bern, Switzerland. Switzerland
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Wildhaus 2021-06-27 06:19:21 Singers: Common nightingale, Willow tit
♫ 2021-06-27 06:19:21 Source: BirdNet 20210627_061921 birdnet 1752 - Common Nightingale, eher alpenmeise - Common Nightingale - Wildhaus.mp3 Wildhaus (song?)
Lugano 2021-04-01 13:35:30 Singers: Willow tit, Coal tit
♫ 2021-04-01 13:35:30 Source: BirdNet 20210401_133530 birdnet 1378 - Willow Tit or Coal Tit - Willow Tit - Lugano.mp3 Lugano (song?)
Carona 2021-04-04 14:05:46 Singers: Willow tit, Marsh tit
♫ 2021-04-04 14:05:46 Source: BirdNet 20210404_140546 birdnet 1408 - Willow Tit and-or Marsh Tit (uncertain) - Willow Tit - Morcote.mp3 Carona (song?)
Willow tit st moritz noisy until 50. Sils 2020-06-09 16:09:28
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