Black kite / Schwarzmilan (Milvus migrans)

Black kite in the air and on the ground Source: WIKIPEDIA Wikimedia Black_Kite_(Milvus_migrans).jpg
Classification: Genus Milvus; Subfamily True hawks (Accipitrinae); Family Accipitridae
This is on my list of birds to find, as it is supposed to be exist in this area,but I've never identified one. Their call (see Vogelwarte link) is a rapid sequence of whistles, and definitely distinct from that of the red kites. Visually they are harder to tell apart, but if you look closely, it should be clear: the black kite has less of a V in its tail and no big white patch at the wingtips. birdguides.com has a guide to distinguishing black and red kites, and says black are much rarer, but that is not true in Switzerland - Vogelwarte.ch says Switzerland has 2800–3500 red kites and 2000-3000 black kites.
Tenatively identified one flying high over Lake Lugano at San Salvatore in Ticino.
Often near water.
Vocalization: A piercing, first ascending then descending long "piuuu". Starting as a clear tone then gradually taking on a vibrating character that differs from Red Kite. Also a sharp "kieee -ki- ki-ki". More vocal than Red Kite. [Link]
Physical details: length=55-60 cm, wingspan=160-180 cm, weight=630-941 g
Habitats: Agricultural

Song: Automatically generated from Xeno-Canto recording.
Song attributes: Frequency:
♫ 2021-08-14 09:32:55 Source: BirdNet 20210814_093255 birdnet 1932 - Wild guess was once black kite, check - Not analyzed - Volketswil.mp3 (song)

Call: Drei fallende Noten

XC884100 - Black Kite - Milvus migrans - flight call.
♫

Call attributes: flight call Call melody: simple rhythmic, slow, Frequency: medium (1-5 KHz), Special sounds: swoop.
First documented observation: 2021-04-03 in Carona. Most recent observation: 2022-05-22 in Leuk and surroundings.