Hall, K. J, Norman, D. M & Pym, A / June 1985 – vol. 78, issue 6, pp 303–306 Bill coloration of treecreepers. The note by Laurel Tucker (Brit. Birds 77: 263-264) questions if the upper mandible coloration could assist in the field separation of the two European treecreepers Certhia. Photographs, in Vara Figlar i Norden (1942) by C. T. Holmstrom et al. and in Atlas o fEuropean Birds (1960) by K. H. Voous, show Treecreepers Certhia familiaris of the northern race familiaris ... This article is only available to registered users.To read more, please log in or purchase a subscription.