Influence of flow on locomotion, feeding behaviour and spatial distribution of a suspension-feeding sea cucumber

Abstract

Although movement in response to environmental conditions represents a fundamental link between animal behaviour and population ecology, it is rarely investigated in suspension feeders because they are generally perceived as sessile. Here, the interplay between water flow and fine locomotor and feeding behaviours was experimentally investigated for the first time in a free-moving suspension-feeding sea cucumber (; Echinodermata, Holothuroidea) using time-lapse videography in a mesocosm setting. Individuals moved away from static conditions in the weakest flow treatment and fled the strongest flows (>40 cm s) in the more dynamic treatments. The tentacles of individuals located in areas with flows of ≥40 cm s was aligned with the direction of the current, whereas in flows <40 cm s, they were typically perpendicular to the direction of flow. Tentacle deployment and insertion rates (i.e. feeding rate) increased with flow, from 0.95 min at 10 cm s to 1.13 min at 40 cm s Three modes of locomotion were detected. Forward crawling was most frequent at flows ≤40 cm s, passive rolling dominated at flows >40 cm s and active rolling occurred randomly at flows between 0 and 120 cm s Overall, the flow regime favoured by was determined to be between 21 and 40 cm s, under which an optimal balance between efficient food capture and energy expenditure for attachment to the bottom was presumably found. These findings provide insight into the distribution and population dynamics of suspension-feeding holothuroids, and may also assist the fisheries management and aquaculture development of commercial species.

Cellular, Hormonal, and Behavioral Responses of the Holothuroid Cucumaria frondosa to Environmental Stressors

“…The force of attachment of the ambulacral podia to the substrate was also used (Hamel et al, 2019). Detachment from the substrate combined with increased motility through active buoyancy adjustments have been triggered by high conspecific densities, encounters with predators, sudden decreases in salinity, and increased turbidity (Sun et al, 2018;Hamel et al, 2019).…”

Consumers' attention on identification, nutritional compounds, and safety in heavy metals of Canadian sea cucumber in Chinese food market

“…There are many alias names of Cucumaria frondosa, such as Orange-footed sea cucumber, Northern sea cucumber, Atlantic sea cucumber, Canadian sea cucumber, or Icelandic sea cucumber (Nelson et al, 2012). It mainly geographically distributed at depths of 30-100 meters in the North Atlantic Ocean (Zhao, Lin, & Liu, 2016;Sun, Hamel, & Mercier, 2018), such as the coast of New England (USA), the eastern coast of Canada, Iceland and Greenland, F I G U R E 3 Characteristics of sea cucumber from Canada (a. overall; b. body wall and tube foot after soaking; c. inner wall and rib after soaking; d. cross-section after soaking.) down the coast of northern Europe and Scandinavia, as well as in the Faroe Islands ( Figure 2).…”

Plasticity of Respiratory Function Accommodates High Oxygen Demand in Breeding Sea Cucumbers

“…The respiratory tree is a specialized organ for gas exchange and excretion in sea cucumbers, anatomically attached to the cloaca by connective tissue (Gao and Yang, 2015). Therefore, the respiratory rate can be determined by cloacal movement (Gianasi et al, 2015;Sun et al, 2018a).…”