Ortolan bunting / Ortolan (Emberiza hortulana)

Wikipedia: Ortolan bunting Source: OTHER 1200px-Ortolan_bunting_in_Sierra_de_Guara%2C_Aragon%2C_Spain.jpg
Classification: Genus Buntings (Emberiza); Tribe Emberizini (Emberizini); Subfamily Emberizinae (Emberizinae); Family Fringillidae (Fringillidae)
critically endangered Nur 1-5 Brutpaare in der Schweiz nach Vogelwarte.ch
Vocalization: Distinct bunting-like timbre with very prominent harmonics. [Link]
Song: Song simple, but varies from region to region. Sometimes structurally similar to yellowhammer, but slower, more melancholic, and with more clearly audible harmonics f.ex. "tze-ti tze-ti tze-ti tweeeee". Beginning with repeated alternating notes (tze-ti) and ending on a lower note fading out with a rising pitch. Sometimes without the ending note (like yellowhammer). [Link]
Calls: Calls: a vaguely House Sparrow-like "chepp", with a ringing quality, and a sharper cut-off "zeep". [Link]
Physical details: length=16-17 cm, wingspan=23-29 cm, weight=81-96 g
Habitats: Agricultural

Song: First about 4 hlhlhlhl then a single higher or lower note
Song attributes: Melody: stereotype melodic (hlhlhlhl), fast, Frequency: 3-5 KHz
XC726530 - Ortolan Bunting - Emberiza hortulana - song recorded in Spain, first 4 hlhlhlhl then a single higher note. Spain Melody: hlhlhlhl
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XC727606 - Ortolan Bunting - Emberiza hortulana - song, first 4 hlhlhlhl, then 1 or 2 swoops. Melody: hlhlhlhl
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XC652668 - Ortolan Bunting - Emberiza hortulana - first 4 or so hl, then a lower note - seems the close is highly variable. Melody: hl
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🔍 No documented observation