In 1994 Lukas Jenni, a researcher at the Swiss Ornithological Institute, together with Raffael Winkler, published a book called ‘Moult and ageing of European Passerines’ which quickly became a reference work especially for ringers, but also for any serious ornithologist interested to learn in detail how European passerines moult. Probably because the initial printing of the book was not very ambitious, in a short time it was sold out and, in fact, whoever owned an original copy at the beginning of the 21st century (better not to mention copies obtained by questionable methods) had a real treasure.
With very good judgment, in 2020 this fantastic book was reissued and, as wanting to give a gift to the community, the couple of authors published a new one: ‘The biology of moult in birds’. The first is somewhat more practical -although it is not a field guide-, since its main body consist of a multitude of photographs that illustrate the different moulting stages of many European passerines. The second, on the other hand, is a theoretical treatise that delves into the moulting of birds in the most entertaining way possible.
Feathers are fragile structures that, due to wear, must be replaced periodically in a process called moulting. This process, in addition to being quite expensive energetically speaking, has serious effects on all the aspects of bird life: moulting determines, for example, their appearance and also conditions their annual biological cycle.
Lukas Jenni is a consummate specialist in all these matters and will share some of his expertise with all of us in a highly anticipated conference at the Delta Birding Festival.