Eurasian blue tit host is "Proctophyllodes stylifer". However, this mite seems to be of no concern to the bird as, until now, it is only known to feed on dead feather tissue. "P. stylifer" lives all its developmental stages, i.e. egg, larva, protonymph, tritonymph and adult, within the plumage of the same host. The usual sites where "P. stylifer" is encountered are the remiges and the rectrices of the bird where they can be found tandemly positioned between the barbs of the rachis. The Eurasian blue tit is classified as a least concern species on the IUCN Red List (version 3.1), and as
What Bird is That? Edition What Bird is That?" was published by Australia's Heritage Publishing in 2011, the latest release of Cayley’s “big bird book” complete with Lindsey’s revisions. It is 832 pages, features 769 birds and includes all 460 of Cayley’s full-colour paintings, many showing groups of related birds. New to this edition was an accompanying e-book "What Bird Call is That?", which identifies and illustrates 101 birds from "What Bird is That?", as well as providing sound files of each featured bird’s distinctive call. The sound files were provided by David Stewart. "What Bird is That?" plays a central role in Australian