AUTHOR=Chen Mengling , Sun Shuo , Xu Qiang , Gao Fei , Wang Haiqing , Wang Aimin 

TITLE=Influence of Water Temperature and Flow Velocity on Locomotion Behavior in Tropical Commercially Important Sea Cucumber Stichopus monotuberculatus

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2022.931430

DOI=10.3389/fmars.2022.931430

ISSN=2296-7745

ABSTRACT=Aquaculture and sea ranching can help replenish depleted sea cucumber stocks and mitigate fisheries impacts on wild populations. While advances have been made in the nursery rearing of sea cucumber Stichopus monotuberculatus, the influence of environmental factors on its locomotion behavior remains less understood, which restricts the establishment of mariculture technologies. In the present study, locomotion behavior of S. monotuberculatus under different temperatures and flow velocities were examined through controlled simulation experiments. Results showed that the creeping activities were obviously affected by temperature, and the most active movement and feeding behavior were recorded at relatively high temperatures. Diurnal variation of locomotion and feeding activities indicated that S. monotuberculatus displayed an evident nocturnal activity pattern, being the most active at night, exhibiting intermediate activity at dusk, and minimal activity during the daytime. The movement velocity decreased with the increasing flow speed and was only 1.65±1.35cm·min-1 in the highest flow rate group (20.8±3.4cm/s). Moreover, the sea cucumber S. monotuberculatus displayed positive rheotaxis behavior of moving downstream at all flow velocities. Overall, the sea cucumber S. monotuberculatus exhibited high locomotor and feeding activities at night of relatively high temperature, and its favoured flow regime was downstream and low water velocity area. These findings may assist the sea ranching and aquaculture development of the tropical commercial sea cucumber species.