At first, I do have to congratulate Jelmer Huisman with his book. It took years in the making, and he published it by himself. It contains as the title implies, data on all Estrildid Finches of the World. It is lavish illustrated with photographs of this fantastic birdgroup. In special the beaks of the Estrildids are unique. After a brief introduction of the species group, the author gets into the species texts.
The information supplied in the species text, is clear, and no less than six languages can be found for each species (as off course the scientific name). The distribution maps are splendid and in combination with the subspecies in the text give a clear view where these taxa can be found. The photographs are of the highest standard you could expect, it must be a monstrous project to get them all together! And the mouth markings of the juveniles are out of this world! Diet, reproduction, and behavior might fill a gap in knowledge for the avicultural sector.
Some remarks for a second addition would be.
• The taxonomy follows HBW 2019 but has some author’s additions (p. 14). One source would help to understand taxonomy better, then some exceptions.
• Also, it would be good to know how (source, for example e-bird) the author establishes the distribution maps in the books (p. 19).
• The subchapter in the species text ‘general’ varies within all taxa, sometimes the author dives into of the Latin name, sometimes the English name and sometimes discusses the author of the taxon discussed. A vast format in this subchapter would help very much to have a uniform discussion in each of the texts.
• Within distribution the author already explained on page 19 what abbreviations are used, but when reading the text under ‘Distribution’ we still find the whole names (see pages 26, 28 for example). For the description for ‘identification’ only male, female and juvenile exist, other plumage states are not discussed (for example post-juvenile / immature, 1st-autumn). Also, the general terminology used, doesn’t follow the terminology as discussed in for example Clement et al (Finches & Sparrow, pp 14-15).