航空観察によつて得られた流れ藻量からモジャコ資源量を推定する1つの試み-IV : モジャコの漁獲率
スポンサーリンク
概要
- 論文の詳細を見る
The present paper deals with the rate of exploitation of the “mojako”, the juvenile of the yellowtail, Seriola quinqueradiata TEMMINCK et SCHLEGEL, in the sea west off Kyushu based on the investigations for the purpose of an assessment of the effect of fishing the “mojako” on the maintenance of yellowtail stock. The investigations under report were carried out during the period from the end of May to the middle of June, 1965. The methods of survey are the same as those of the 1964-survey, and the details were already given in the previous papers (References 1), 2), and 3)). Dates and areas of the surveys in 1965 are shown in Table 1 and Figs. 1 and 2. The results obtained are summarized as follows: 1) The floating seaweeds are for the most part found in the waters within 50km from the coast (Fig. 6). 2) From the aerial observations, the amount (A) of floating seaweeds is estimated a total of about 530, 000m2 in area or 4, 000 metric tons in weight (Table 3). 3) Population size (N) of the “mojako” is computed to be about 5, 000, 000 fish in number in total through the equation of N=d×A, where d is the density (in number) of the “mojako” per 1m2 of floating seaweeds (Table 3). 4) The rate of exploitation (E) of the “mojako” for the season is calculated at 4.8% for the mid-waters off Kyushu (III in Fig. 6), at 3.6% for the northwestern waters off Kyushu (II in Fig. 6) and at 15.2% for the waters off Yamaguchi Prefecture (I in Fig. 6), while 11.9% for the through waters west of Kyushu, by the equation of Ei=Ci/Ni, where Ci is the commercial catch in number from fishing grounds of the “mojako” (Table 4).
論文 | ランダム
- Connexin32の新しい点変異によるX連鎖性運動感覚性ニューロパチー(ヘテロ接合例)の腓腹神経の組織病理学的所見
- 希釈された肺サーファクタントの機能に対する水溶性非イオン性高分子の効果
- 肺結核の外科的早期治療
- アミピロンの臨牀成績
- モノステアリンの結晶成長(2) : 溶液成長