| Summary: | 碩士 === 國立臺灣大學 === 漁業科學研究所 === 85 === The age of Setipinna taty in the southern Kinmen waters was
determined byvertebral ring-count, and its von Bertalanffy''s
growth equation was estimated by nonlinear regression.
Furthermore, the mesh selectivity of gill net was
estimated by modified Holt''s method (1963), and used to discuss
the influences on the estimation of growth parameters. The
results were as follows: 1. Observed length
frequency distribution ranged from 8.1 to 17.8cm as well as
it showed bimodal. The main mode was at 15.25cm, and the second
at 12.25cm. 2. The annulus of vertebrae was formed
annually, and the period was between winter and spring.
3. The von Bertalanffy''s equation of fork length (cm) was
estimated Lt＝23.45{1－exp[-0.40(t+0.37)]}
4. The optimum selection lengths (lm) and selection factors (k)
of three meshes, i.e., 4.00cm(A), 4.29cm(B), and 5.00cm(
C) were as follows: (a) When fork length
of specimens>14.0cm, Alm=14.8cm, Blm=15.5cm,
Clm=15.8cm, and kA=3.71, kB=3.62, kC=3.17.
(b) When fork length of specimens <14.0cm: Alm=11.7cm, Blm=11.4
cm, Clm=12.3cm, and kA=2.94, kB=2.66,
kC=2.46. 5. The optimum
selection length increased with mesh sizes when specimens
were caught by the wedged pattern, but it didn''t showed same
trend when specimens were caught by the tangled pattern.
6. The mesh selectivity of gill net indeed affects the
estimation of growth parameters.
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