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飼育実験によるカタクチイワシの雌1尾当り年間産卵数の推定
https://fra.repo.nii.ac.jp/records/2003288
https://fra.repo.nii.ac.jp/records/20032886ba1f1d1-417d-4850-ac71-169977dfe309
Item type | 紀要論文 / Departmental Bulletin Paper(1) | |||||
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公開日 | 2024-04-25 | |||||
タイトル | ||||||
タイトル | 飼育実験によるカタクチイワシの雌1尾当り年間産卵数の推定 | |||||
言語 | ja | |||||
タイトル | ||||||
タイトル | Number of Eggs of Japanese Anchovy Produced per Female per Year Estimated by a Rearing Experiment | |||||
言語 | en | |||||
言語 | ||||||
言語 | jpn | |||||
資源タイプ | ||||||
資源タイプ識別子 | http://purl.org/coar/resource_type/c_6501 | |||||
資源タイプ | departmental bulletin paper | |||||
アクセス権 | ||||||
アクセス権 | metadata only access | |||||
アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
著者 |
高尾, 亀次
× 高尾, 亀次× 岸田, 達× 上田, 和夫 |
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抄録 | ||||||
内容記述タイプ | Abstract | |||||
内容記述 | Since 1978 the Nansei Regional Fisheries Research Laboratory has estimated the abundance of adult anchovy (Engraulis japonica (HOUTTUYN)), based on the egg census, in addition to the analysis of catch and effort statistics (TAKAO 1980). The average number of eggs spawned per female is indispensable for conversion of the abundance of eggs in the sea to number of the adult anchovy that produced them. Attempt was made to determine the number of ovarian ova. The long-lasting spawning activities over nine months in the Seto Inland Sea makes it difficult to obtain the number of spawned eggs per female based on merely the counts of ovarian ova. Furthermore the number of eggs in the ovary were found differing from area to area within the distribution range of the species. The authors have commenced rearing experiments of adult anchovy in an outdoor tank of 2 × 2 × 3m to determine actual number of spawned eggs. Fish of 0-age group that hatched in the autumn 1980 were brought to the tank on 23 June 1981, and then kept until October 1982. The fish spawned continuously from late July to early November 1981 and again discharged eggs since April 1982. The death rate stayed at low-level below 0.02% per day except 15 to 18 August 1981 when over-feeding caused mass mortality of 11 to 65%. Nevertheless, the fish actively discharged eggs even on 17, 18 August just in the disastrous decrease in number. During the period of three months since late July, the average eggs production per day per female varied from one to 1, 031, and the accumulated counts reach 15, 400 eggs. A detailed observation were conducted from 19:00 on 17 August to 06:00 on 18 August. The counts for every one-hours were less than ten eggs discharged on the preceeding day before 22:00 and increased since then, having reach a peak of 1, 500 newly spawned eggs at 23:00. After midnight the eggs decreased in number, having dropped to 40 at 04:00 and about 300 at 05:00 and 06:00. The data indicate that the anchovy discharge eggs most actively at 22:00 to the midnight. The long-lasting spawning of the same school in the tank confirms that a single fish spawns more than one batch of a year, even if the activity of reproduction varies remarkably from season to season. The anchovy eggs collected by plankton nets are found most abundant in June in the nearby spawning grounds of the Hiroshima Bay. Thus the accumulated count of 15, 400 eggs per female obtained from the rearing experiment that started on 23 June is definitely an underestimate of the average fecundity of the species. Taking the seasonal change of egg abundance in the sea and the duration of the rearing experiment into account, the authors propose that a female anchovy produces about 21, 000 eggs per year. | |||||
言語 | en | |||||
抄録 | ||||||
内容記述タイプ | Abstract | |||||
内容記述 | カタクチイワシ成魚の飼育実験を行い,産卵行動や産卵数について以下の結果を得た。1)飼育した成魚は前年の秋生れ群と推定される。従来,この群は発生した翌年の6,7月に産卵すると考えられていたが,秋まで産卵することが明らかになった。飼育期間中の主たる産卵時期は7月31日から11月2日までであった。2)飼育に供した群は,3ヵ月以上にわたって産卵を持続した。また集団としての産出卵数は季節によって大きく異った。3)本種の産卵時刻は22時~0時の前夜半と推定された。4)年間における雌1尾の産出卵数は21,000粒前後と推定された。 | |||||
言語 | ja | |||||
bibliographic_information |
ja : 南西海区水産研究所研究報告 en : Bulletin of the Nansei Regional Fisheries Research Laboratory 巻 15, p. 1-11, ページ数 11, 発行日 1983-03 |
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出版者 | ||||||
出版者 | 南西海区水産研究所 | |||||
言語 | ja | |||||
出版者 | ||||||
出版者 | Nansei Regional Fisheries Research Laboratory | |||||
言語 | en | |||||
item_10002_source_id_9 | ||||||
収録物識別子タイプ | PISSN | |||||
収録物識別子 | 0388-841X | |||||
item_10002_source_id_11 | ||||||
収録物識別子タイプ | NCID | |||||
収録物識別子 | AN00181988 | |||||
情報源 | ||||||
識別子タイプ | Local | |||||
関連識別子 | nnf_k_15_1 | |||||
関連サイト | ||||||
識別子タイプ | URI | |||||
関連識別子 | https://agriknowledge.affrc.go.jp/RN/2010271217 | |||||
言語 | ja | |||||
関連名称 | 日本農学文献記事索引(agriknowledge) |