A research and data on woodpecker damage to timber and electric poles

Abstract

Local woodpecker damage has been claimed to the Forestry Bureau particulary after the war, and reports were brought also to Yamashina Museum through that Bureau. In this paper, the collected data, home and foreign, summarized by the author are presented, with his recent original research.The foreign data are based on the communications addressed to Dr. Yamashina for his letter of inquiry, and include a valuable paper (about protection of poles by wire-net) by Mr. E. W. Andersson of Sweden (Teknisk Tidskr. '53), who was so kind as to send us a whole English translation of his paper made by his friend. Our acknowledgments are equally due to: Miss Phyllis Barclay-Smith, Br. Sect., I. C. B. P., Mr. M. Laurie, Forest Res. Station, Surrey (England); Mr. Richard Pough, Nat. Mus., Mr. Rea King, Audubon Society (U. S. A.); Dr. Finn Salomonsen, Zool. Mus., Prof. Dr. Mathias Thomsen, Zool. Labor., Copenhagen (Denmark); Dr. Hörstadius, Zool. Instit., Uppsala and Dr. Count Nils Gyldenstorpe, for their kind presentation of data.We express thanks also to Mr. Hisamoto Nijo of Japan Electro-telegraph Laboratory as well as to Mr. Seiichi Kuzu, the Chief of Game Management Bureau, for their kind help.The actual status in Kasuga-mura, Gifu Prefecture, one of the most claimed districts, was visited by the author November 1954, and the result of two-days' survey made by help of Mr. Nobuaki Tanahashi, Prefectural Forest Officer, and Mr. Jinichi Ogura, owner of timber being damaged, is reported. Here, the cryptomeria is most damaged, few to over 10 holes per timber, including also few other trees, one bamboo and two electric poles (one is non-wired). They are damaged as no big trees, fit for woodpeckers to make holes, are found in surrounding young second growth (for charcoal) where they feed. And, therefore, to provide them with artificial subsitute block of timber or to plant big trees for future, will be recommended as a remedy. Before winter, the bird makes many half-dug holes at the same time, few of them being completed as hide and resting place. Thus, a bird (only one D. leucotos was seen) seems to work a fairy wide area.Damage in Europe and America seems to be confined to electric poles. In Japan, experiments were made about this subject by Kaburaki & Kuzu at Karuizawa (1950) and by Nakajima, Miyazaki University, in Kyushu (1954).