Effect of Water Temperature Condition on Growth and Survival of Juvenile Geoduck (Panopea japonica A. Adams, 1850)

Abstract

This study was performed to determine the effect of water temperature condition on survival rate and growth of juvenile geoduck (Panopea japonica). Panopea japonica juveniles were bred for 6 weeks at 12, 15, 18, 21, 24 and 27℃ on incubator. Juveniles median lethal times (LT50) were 29 hours in 27℃, 14.5 day in 24℃, 37.4 day in 21℃. Survival rate of water temperature 12, 15 and 18℃ showed a high survival rate in 95.0%, 95.0% and 93.3% at 6 weeks. As a result of culturing for 6 weeks at 12, 15, 18, 21 and 24℃, a daily growth of shell length and total weight was 0.10 mm, 0.12 mm, 0.13 mm, 0.16 mm and 0.14 mm, and 2.21 mg, 2.65 mg, 2.84 mg, 3.13 mg and 2.93 mg. Juvenile shell length and total weight have significantly increased at 15-21℃. However, mortality rate has significantly increased at more than 21℃. As a result, appropriate water temperature for juveniles culturing considered 15-18℃. (Fig 1). 중국과 홍콩에서 80-90% 정도가 소비되고 있다 (Shamshak and King, 2015). 캐나다의 브리티시 컬럼비아주와 미국의 워싱턴주에서 는 P. generosa 종을 자연에서 대량 채취 및 대량양식하고 있 으며 (Beattie and Blake, 1999), 미국의 알레스카에서는 P. abrupta 종을 제한적으로 채취하며, 멕시코의 캘리포니아 만 에서는 P. generosa와 P. globose를 채취하고, 뉴질랜드에서 는 P. zelandica를 채취하고 있다 (Andersen, 1971; Beattie, 1992).

Effects of temperature on early development of the New Zealand geoduckPanopea zelandica(Quoy & Gaimard, 1835)

“…The developmental rate of P. zelandica in the present study also increased with increasing temperature. This is in agreement with several other studies on marine invertebrates that have shown that higher temperatures tend to enhance the rate of cleavage of the developing embryos up to a certain point (Chen & Chen, 1992;Dehnel & Kong, 1979;Delorme & Sewell, 2013;Dos Santos & Nascimento, 1985;Huo et al, 2017;Lee & Rho, 1997;Nam et al, 2015). The developmental rates at recorded temperatures in the present study are similar to those observed by Le et al (2018) on P. zelandica (at 15°C) and by Lee and Rho (1997) on P. japonica (at 11, 14, and 17°C).…”

“…The developmental rates at recorded temperatures in the present study are similar to those observed by Le et al () on P. zelandica (at 15°C) and by Lee and Rho () on P. japonica (at 11, 14, and 17°C). Nam et al () further shortened the incubation time of P. japonica to reach D‐veliger larvae to 27 hr by maintaining the embryos at 19°C. While it may be beneficial for hatcheries to maximize the developmental rate, the thermal threshold for normal development should not be exceeded (Delorme & Sewell, ; Dos Santos & Nascimento, ; Huo et al, ; Parker, Ross, & O’Connor, ; Parker et al, ), as the percentage of abnormalities appears to greatly increase with increasing temperatures.…”