Breeding biology of the Stonechat in southeastern Hokkaido, Japan
その他（別言語等）
のタイトル
北海道南東部におけるノビタキの繁殖生態 著者（英） Fujimaki Yuzo, Takamata Masako, Sato Fumi journal or
publication title
Research bulletin of Obihiro University.
Natural science
volume 19
number 1
page range 37‑46
year 1994‑10‑07
URL http://id.nii.ac.jp/1588/00001943/
Res. Bull. Obihiro Univ.， 19 (1994) : 37‑46
Bre巴dingbiology of the Stonechat in southeastern Hokkaido， Japan Yuzo FUJIMAKI'， Masako TAKAMATA' and Fumi SATO'
(Received : May 24， 1994)
Abstract
Breeding biology of Stonechats ，Sαxicolαtorquata、wasstudied for 9 years in an ag‑
ricultural land in Obihiro， Hokkaido. Stonechats arrived at the breeding area in mid‑April and departed by mid‑October. Return rate in the following breeding sea‑ son was 52 % for males and 19 % for females. Breeding density was 0.8 to 1.0 nests/ha in a semi‑natural grassland (A)， and 0.4 to 0.5 nests/ha in an unsuitable habitat composed mainly of cultivated fields and pastures (B)， The average dis‑ tance between neighbouring nests was 110 m in A and 179 m in B. Successful Stonechats had two broods in a season， the first breeding beginning at late April to early May， and the second at late June or early July with the active egg‑laying period in mid‑May and from late June to early July respectively. The interval between suc‑ cessive breeding was 46 days. The breeding cycle from nest‑building to young inde‑ pendence was about47 days; average nest‑building， egg‑laying， incubation， nest1ing and post‑fledging periods were 5.3， 5 ‑6， 13.6， 13.4 and 10 days respectively. The average clutch size was 6.3 and 5.6， the average brood size was 5.8 and 4.5， the average number of young fledged was 5.7 and 44， .and breeding success was 67.3%
and 60% for early and late breeding respectively
Key words : stonechat， Sαxicolαtorquαtα， breeding， Hokkaido
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The Stonechat Sαxicola torquatαlS a summer visitor and occurs on most open habitats， in‑ cluding pastures， cu1tivated fields， native grass‑ lands， young plantations， alpine meadows， vacant lot of urban areas， from sea level on the sea coast to nearly 1，400 m at alpine zones throughout Hokkaido. In agricultural lands and native grasslands this species/is an abun‑
dant and conspicuous breeding speCles
(NAKA~IURA etαl. 1968， FUJL¥lAK11984， FUJL¥lAKI
& TAKA~l 1986) and might play an important role in bird communities of such叩 en habiー
tats. In Japan only few studies have been pub‑
lished on social structure and breeding habi‑ tat (K"CAWA & IDB 1973. E'DO & HlRA"O 1983， IIDA&TANAKA 1990)， but breeding biology of this species has not been previously studied
This paper describes breeding biology of the Stonechat at an agricultural land in southeast‑ ern Hokkaid。
Study areas and methods
The breeding data were collected at the farm of the Obihiro University of Agriculture and
I Laboratory of Wildlife Ecology， Obihiro University of Agriculture and Veterinary Medicine， Inada， Obュhiro080， Japan
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