著者

斉藤 憲治 片野 修 小泉 顕雄

出版者

日本生態学会

雑誌

日本生態学会誌 (ISSN:00215007)

巻号頁・発行日

vol.38, no.1, pp.35-47, 1988-04-30

被引用文献数

69

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Paddy fields and ditches around irrigation creeks constitute temporary waters flooded only in summer. In order to consider the significance of such temporary waters for fishes, the movement and behaviour of fishes in temporary waters and a permanently filled creek were investigated near the town of Yagi, Kyoto Prefecture. Among twenty-three species identified in the study area, seven species frequently entered the temporary waters, six of which utilized these waters as spawning sites. Two species were seldom found in the temporary waters, in spite of their abun dance in the permanent creek. The remaining fourteen identified species were rare in the study area. Fishes which frequently utilized the temporary waters for spawning had a similar reproductive habit, i. e., they scattered many eggs widely and showed no parental care. It is considered that many fishes, including juveniles, were foraging on the plankton which became abundant in the temporary waters after irrigation. It is surmised that newly emerged habitats of temporary waters with high productivity serve for the maintenance of a rich fish fauna in irrigation creeks.

著者

片野 修 斉藤 憲治 小泉 顕雄

出版者

The Ichthyological Society of Japan

雑誌

魚類学雑誌 (ISSN:00215090)

巻号頁・発行日

vol.35, no.2, pp.203-211, 1988-09-20 (Released:2010-06-28)

参考文献数

19

被引用文献数

13

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Reproductive behaviour of the catfish, Silurus asotus was studied in temporary waters around paddy fields. Spawning occurred nocturnally during the first week from the initiation of irrigation. In reproductive activities, a male first energetically pursued a female with its head near to the female's belly (chasing) and then began to cling to the female's body from the side, bending its tail or head (clinging). Finally the male enfolded the female's body, with its anus near to the female's (enfolding). In some cases, 2-4 males pursued a single female and two males enfolded a female at the same time. Although no aggressive behaviour was evident between males, it was always the largest male that could most frequently approach and enfold the female. The mating pair moved a long distance in a ditch, paddy field and/or creek, performing reproductive activities. It is thought that the spawning site and period of spawning of the fish enable the larvae to avoid the danger of predation and to efficiently feed, firstly on plankton and later on larvae of other fishes which become abundant during the irrigation period. Although some eggs and larvae may die due to the drying out or high water temperatures of such unstable temporary waters, scattering eggs may reduce the incidence of the annihilation of the young.