Maarten Wielstra
 ·  24 November 2019  15:13, gewijzigd 24 November 2019  15:30

Mmmm, het plaatje valt weg. Zie voor sonogrammen en eenzelfde geluid van Italiaanse: https://www.dutchbirding.nl/gallery/detail/23912?page=0#navbar-collapse

Maarten Wielstra
 ·  15 May 2020  21:41, gewijzigd 8 June 2020  03:36

It seems there are some features of the sonogram of the call pointing strongly to this subspecies instead of Italian and feldegg:

-A modulated part that's very shaky instead of needly organised (creates a more house sparrow like sound instead of a lark like sound of the other two)

-The teeth in the saw fall down in frequency continuously, instead of flattening off horizontaly (or even creating an ''extra'' top) at a certain point. There could be some overlap with the other two taxa.

-Iberian modulates more slowly compared to the other two taxa (ca.25%).

-Iberian seems to modulate lower in frequency compared to most Italian (except for intermediate birds assigned as Italian).

-Iberian regularly make flava-like calls, without or with very few modulations. Italian possibly never does this. The flava-calls recorded on Corsica turn out to be...calls from flava! Feldegg also makes ''smooth'' calls.

-Iberian flava-like calls often have a ''M''-shape modulation halfway or subterminal in the second part of the call. This seems is less pronounced and rare in feldegg.

-Iberian sometimes calls with a shallow 'saw' structure, resembling other wagtails. Features pointing towards Iberian seem a continuously descending saw instead of a 'bow' (cf. some perched Italian and western feldegg - having bigger amplitude) and a typical first part on the sonogram fitting Iberian/Italian (more space between two ''sticks'' and a more stretched out ''hook'' on the right stick - cf. eastern feldegg and some Eastern Yellow Wagtail). Pitfalls could be Iberian birds with a ''narrow first part'' on one hand and wintering feldegg (Ethiopia) on the other hand.

I'll update this everytime I find something new (while searching for differences between Italian and Black-Headed)... (8 June 2020)

https://www.dutchbirding.nl/gallery/detail/24348#r1965015

https://www.dutchbirding.nl/gallery/detail/24454?page=0#navbar-collapse