Summary: | 碩士 === 國立海洋大學 === 漁業科學系碩士在職專班 === 91 === Summary
1. Snapping shrimps Alpheus brevicristatus inhabit in the segrass meadow or sandy bottoms at the intertidal zones of Peng-hu. They are commonly used as fishing baits or even for food if reach larger body sizes.
2. The results of investigations showed that Alpheus brevicristatus distributed at sixteen sites in Peng-hu so for. Its highest population density reached 5 ind. /m2 in Chi-to Bay. Four species of symbiont gobyfishes were discovered. Acentrogobius pflaumill was the most widely distributed and with must individuals.
3. The results of morphological characters measurements of male or female Alpheus brevicristatus :
(1) The linear regression equations between body length (B. L.) and carapace length (C. L.): female : B. L. =-0.4583 + 3.0525 × C. L. (r2 = 0.9357, N= 487) and male: B. L. =1.404 + 2.7823 × C. L. (r2 = 0.8726, N=254).
(2) The curve regression equations between body weight (B. W.) and body length larger (B. L.): Y= 0.0009 X2.9307, (r2 = 0.9782, N= 99) and male : Y= 0.0005 X3.2219, (r2 = 0.9520, N= 67) . The indiridnals with body lengths larger than 40mm are all female.
4. This study snggests that Alpheus brevicristatus in Peng-Hu should be perennial iteroparous life cycle. The gravid period is between February to December and with climax in May. However, annual temperature fluctuation is small and variation curve is slow. It will have extended gravid period and higher - fertility. The gravid period will be also extended with elevated monthly average temperature.
5. Under the controlled condition for artifical reproduction with salinity between 3.2-3.4% and with temperature between 24-27.5℃, it takes about 10days for larvae to hatch from the female gravid stage. It take 30days for larvae to go through 9 stages of zoea before metamorphosis to juveniles. The larvae of Alpheus brevicristatus are with common type developmental mode.
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