ウマヅラハギNavodon modestusの体長－体重関係について

瀬戸内海で漁獲されたウマヅラハギの体長－体重の関係式を求めるについて,標本を未成魚と成魚に分け,成魚は雌雄別に,また産卵期とそれ以外の時期とに分けて,それぞれをAllometryの方法によって表わした。これらの関係式は成魚と未成魚で異なり,さらに前者は雌雄間でも異なると同時に産卵期とそれ以外の時期とでも異なることを統計的方法により検討して示した。すなわちウマヅラハギの体長－体重関係は未成魚(体長18cm未満)と成魚(体長18cm以上)に分けて扱うこと,さらに成魚は雌雄別にそして産卵期のものと産卵期以外のものとに分けて扱うことが必要である。そしてそれぞれの群について求めた体長(L)と体重(W)との関係式は次の通りである。

未成魚; W=2.196×10-6 L3.4649
産卵期の成魚の雄; W=5.024×10-5 L2.8519
産卵期の成魚の雌; W=1.517×10-5 L3.1242
産卵期以外の成魚の雄; W=1.703×10-4 L2.6168
産卵期以外の成魚の雌; W=5.005×10-5 L2.8632

The present paper aims at clarifying the length-weight relationship of file-fish, Navodon modestus GÜNTER. The samples are of immature and adult fishes collected from the catches of a small set net and a gill net, from October in 1964 to May in 1965 in the Seto Inland Sea. The adult fishes consist of the spawning cluster sampled in May and the non-spawning one sampled in the months from October to January.

The samples was divided into six groups: immature male fishes, female ones, males of spawning cluster, females of spawning cluster, males of non-spawning cluster and female of non-spawning cluster. The length-weight relationship of each group was expressed by the Allometric method. The results of statistical analysis of Allometry formula W=αLβ, or w=k +βl by ITO10) were applied to the length-weight relationship in each group of the file-fish. A test of significance of "slope and positional differences" of length-weight lines was used for comparison of two groups. As results, the following equations expressed by the Allometric method were obtained for each group:
Immature file-fish; w = 2.196×10-6 L 3.4649
Male of adult sampled in the spawning season;
W = 5.024×10-5 L2.8519
Female of adult sampled in the spawning season;
W = 1.517×10-5 L3.1242
Male of adult sampled in the season except the spawning season;
W = 1.703×10-4 L2.6168
Female of adult sampled in the season except the spawning season;
W = 5.005×10-5 L2.8632