高知県東洋町の生見海岸におけるアカウミガメの卵を狙う野生動物
渡邊真子・谷地森秀二・斎藤知己・加藤元海
Ikumi Beach in Toyo Town, is known for a nesting site of loggerhead turtles in Kochi Prefecture. All nests have been relocated to a safety site to prevent eggs from being hit by waves. Predation on turtle nests by wild animals was first reported in 2010. and predation occurs every since then. Automatic cameras with an infrared sensor switch were used to identify the suspected animals of predation. Animals observed by the cameras around the beach were dogs, foxes, raccoon dogs, cats, masked palm civets, deer, hares and mice. Animals observed by the camera at the relocated nest were dogs, foxes, cats and crows. A video taken by the camera showed that foxes excavated the relocated nest and preyed on eggs, suggesting that the foxes are the suspicious animals of predation at this beach. In addition, another video showed that a crow excavated and picked an egg in its mouth. Because the crow appeared after the fox predation, the crow predation may be considered as a secondary effect of the foxes.
高知市浦戸湾の干潟における水辺の鳥
楠瀬雄三・福井 亘
A list of Avifauna at the 4 tidal flats of Urado Estuary in Kochi Prefecture were investigated for the waterfowl species in 2014-2016. A total of 873 individuals and 16 species were found on those tidal flats. This paper shows the list of waterfowl in the study site.
高知県四万十町市ノ又風景林の風倒ギャップにおけるヒノキの更新
下村一真・比嘉基紀・酒井 武・杉田久志・石川慎吾
To assess influences of light and substrate conditions on Hinoki cypress Chamaecyparis obtusa(Sieb.et Zucc.)Endl. establishment in warm-temperate mixed forest,size structures of canopy trees and tree species composition within a gap formed by uprooting of a canopy tree in 1997 were compared to those under the closed forest in Ichinomata Conservation FOrest, Shikoku, Japan. In the study site, Hinoki cypress were dominant in the forest canopy; however, there were no seedlings(H<1.3m) and saplings (GBH<15cm,H≧1.3m) under the closed canopy. Within the uprooting gap, we found 13 and one individuals of seedlings and saplings, respectively. The established seedlings, however, were found on stable bare gound but not found on unstable colluvial slope. The existence of seedlings and saplings of Hinoki cypress within the gap may be due to the improvement of light condition by gap formation, and removal of litters that prevent seedling establishment. These results suggest that gap formation may contribute for Hinoki cypress estabulishment, but other factors, such as existence of litters and ground stability, are important as well.
高知県から得られたニシン科魚類カタボイワシ Sardimella lemuru の記録および本種の日本における出現状況
畑 晴陵・本村浩之
The clupeoid fish Sardinella lemuru Bleeker, 1853 is recorded for the first time from Shikoku Island,Japan, on the basis of a single specimen (215.7mm standard length) collected by seine net in the waters off Kochi City. The specimen is described and a photograph provided. The distribution of S. lemuru in Japanese waters, including confirmed records from Kyushu, the Japan Sea, Seto Inland Sea, and Sagami Bay , is discussed.
コウモリ用模擬枯葉を利用したヤマネ Glirus japonicus (齧歯目:ヤマネ科)
谷岡 仁
In the Shikoku mountains, during a study of bats(Murina ussuriensis) with artificial shelters, I once observed a Japanese dormouse (Glirulus japonicus) occupied it in daytime. I also found circumstantial evidence of the dormice using the artificial shelters. One is that stripped plant barks were brought into a small room of the artificial shelter, and another is that the material of the artificial shelter (hemp) was partially untied to fibers. These findings suggest that the artificial shelter has a potential to study wild dormice without using nest boxes.
四国自然史科学研究第10号 要旨
Bulletin of the Shikoku Institute of Natural History NO.10