著者

Tatsuya Amano Mei-Hua Li Hoshiko Yoshida

出版者

The Ornithological Society of Japan

雑誌

ORNITHOLOGICAL SCIENCE (ISSN:13470558)

巻号頁・発行日

vol.9, no.1, pp.49-53, 2010-06-25 (Released:2010-07-10)

参考文献数

20

被引用文献数

8

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Many studies have reported population declines and range contractions of bird species in agricultural landscapes around the world. However, few studies have described population trends of bird species in rice-paddy areas or identified causes of decline in these areas as opposed to other types of farmland. The Greater Painted Snipe Rostratula benghalensis is strongly dependent on rice-paddy areas for habitat. This paper uses the results of local field surveys and national survey data to document the population trends of Greater Painted Snipe in Japan. Field surveys conducted in Ibaraki Prefecture indicated a severe decline over a recent 10-year period. Data from the National Surveys on the Natural Environment also showed that the distribution of the Greater Painted Snipe has decreased nationwide from the 1970s to the 1990s. This population decline might be due to (1) the introduction of an efficient drainage system in rice fields and/or (2) a reduction in the area of flooded fallow fields with short vegetation at both breeding and wintering sites. Further work on the conservation status of this species is urgently needed.

著者

Satoko Yasumoto Yasuhiro Yamaguchi Hoshiko Yoshida Morio Matsuzaki Kensuke Okada

出版者

CROP SCIENCE SOCIETY OF JAPAN

雑誌

Plant Production Science (ISSN:1343943X)

巻号頁・発行日

vol.15, no.1, pp.23-31, 2012 (Released:2012-01-17)

参考文献数

24

被引用文献数

3

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We examined 50 cultivars of sunflower (Helianthus annuus L.) for their resistance to birds in a field experiment to find parental plants for breeding. Two cultivars, Armarvirskij3497 (from Russia) and Line-41 (from Myanmar), had bird-resistant characteristics. The laboratory bird feeding test indicated that the factors associated with bird resistance were globular seed shape and heavy seed coat, because the main bird feeding on sunflower, oriental greenfinch Carduelis sinica, is relatively small and have difficulty pecking large and globular seeds. Although the two cultivars had unfavorable characters such as low tolerance to lodging and late maturity, the oil contents of their seeds was not significantly lower than that in the susceptible cultivar (63M80). The present findings suggest that Armarvirskij3497 and Line-41 are candidate parental materials for breeding bird-resistant sunflower cultivars without losing seed oil productivity.