Growth and survival rate of juvenile sea cucumbers (Holothuria tubulosa, Gmelin, 1788) at various temperatures [Farklı sıcaklıklarda deniz hıyarı (Holothuria tubulosa, Gmelin, 1788) genç bireylerinin büyüme ve yaşama oranı]

The effect of various water temperatures on growth and survival rate of juvenile sea cucumbers (Holothuria tubulosa) had been investigated in this research. Average weight of 20.48±2.33 g of juvenile sea cucumbers were collected from the coastal zones of Aegean Sea by scuba diving. After the adaptation period, juveniles were placed into glass aquaria which have 4 different sea water temperatures and researched for 45 days under laboratory conditions. Sea water temperatures of trial groups were selected among the minimum (winter) and maximum (summer) temperatures recorded at the natural habitat of H. tubulosa juveniles. Thus, 4 temperature group were selected as 15, 20, 25 ve 30°C. The sea cucumber juveniles were fed on dried and powdered brown algae as references in the literature. The best specific growth rate (SGR) was recorded as 0.288±0.02 % day-1 in 25°C group. The lowest SGR was recorded as 0.085±0.005 % day-1 in 30°C trial group while the negative specific growth rate (-0.03±0.02 % day-1) was recorded in 15°C trial group. The aestivation observed in 30°C and hibernation in 15°C group would be a reason for such lower specific growth rates. The survival rate for all groups were 100% and the best growth performance was recorded in 25°C among others (P<0.05). © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey