Breeding Habitats of Dendrocopos major and D. minor in Urban and Rural Areas

Abstract

Characteristics of breeding sites, nest trees and holes of two woodpecker species, Dendrocopos major and D. minor, were investigated in woods and parks in the urban and rural areas of Obihiro, eastern Hokkaido from April to September 1993. In D. major the numbers of nest and birds counted per 30 minutes census increased with area size, but those of D. minor did not vary. Fledging date ranged from June 23 to July 25 with an average of July 2 for D. major and from July 3 to 20 with an average of July 11 for D. minor. Neither D. major nor D. minor showed any preference in vegetation types of nesting site. Of 42 D. major nests including those found out of study areas, 22 were in woods and 20 out of woods. On the other hand, of 9 D. minor nests, 8 were found in woods and only one nest out of woods. Nest tree height, nest height, DBH (diameter at breast height) and DNH (diameter at nest height) were 13.6m, 3.7m, 35.7cm and 28.2cm respectively for D. major, and 8.0m, 3.0m, 11.0cm and 26.6cm respectively for D. minor. D. major used both live and dead trees for nesting, while D. minor used only dead trees with several holes. The minimum DNH was 19 cm for D. major and 17cm for D. minor respectively. Values indicating nest sizes and volumes of D. major were larger than those of D. minor. Conditions required for nesting of two Dendrocopos species are 1)minimum area of 1.5 ha where they nested, 2) live and dead trees of more than 21 cm in DBH for D. major and 3) dead trees of more than 18cm in DBH for D. minor.

Nest Holes of Great Spotted WoodpeckersDendrocopos majorand Middle Spotted WoodpeckersD. medius: Do they Really Differ in Size?

“…The small variation in the entrance as compared to other nest-hole dimensions, is most likely to constitute an anti-predator adaptation (see below), and this has been supported by other studies (Kawada 1980, Yamauchi et al 1997, Kosenko & Kaygorodova 2003. In all cited studies the entry widths were the least variable of all hole characteristics.…”

“…The high variation in entrance length seems to be typical of all the populations studied in detail (Yamauchi et al 1997, Kosenko & Kaygorodova 2003, see also Günther & Hellmann 1995).…”

“…Kawada 1980, Yamauchi et al 1997, Wiesner 2001, Kosenko & Kaygorodova 2003, Remm et al 2006, see review in Michalek & Miettinen 2003, Pasinelli 2003.…”

“…Moreover, the data covering detailed characteristics of nest-hole dimensions of each species are scarce (e.g. Yamauchi et al 1997, Kosenko & Kaygorodova 2003, Remm et al 2006, see also review in Michalek & Miettinen 2003, Pasinelli 2003. As yet, we have not found any study referring to the nest-hole size of Great-and Middle Spotted Woodpeckers living in syntopy.…”

The effect of the fungus Phellinus hartigii on woodpecker habitat quality in Hokkaido, Japan

“…In order to develop effective management plans for woodpeckers, much information has been gathered, such as on the vegetation surrounding nest trees (e.g. Yamauchi et al 1997;Adkins Giese & Cuthbert 2003) and the characteristics of suitable cavity trees, snags, or stubs (e.g. Runde & Capen 1987;Swallow et al 1988;Conner et al 1994).…”