For the article Measurement of relative bill length of Black-tailed Godwits from photographs by Jan Bisschop (Dutch Birding 43 (2): 113-119, 2021), a large number of photographs on the internet has been analysed. A list of the links can be downloaded here.
Measurement of relative bill length of Black-tailed Godwits from photographs
9 april 2021 · Jan Bisschop · 1357 × bekeken