Controlled spawning and rearing of the sea cucumber, Parastichopus tremulus

Abstract

The red sea cucumber, Parastichopus tremulus, a cold water species with commercial potential, has recently attracted attention for wild harvest as well as for potential use in integrated multi-trophic aquaculture in Scandinavian countries.Overharvesting has put natural stocks of sea cucumbers at risk in several countries. Our goal was to develop a rearing protocol for P. tremulus to enable sustainable production of this species. This study presents results from spawning and larval rearing conducted in both Norway (NO) and Sweden (SWE) during May-August 2019. We describe spawning induction and behavior, fertilization success, embryonic and auricularia larval development rate for this species under laboratory conditions. The larvae were fed a mixture of three species of live microalgae (SWE) and algal paste (NO).Larval development rate and survival were monitored at four different temperatures (7, 10, 13, and 16 C). Results showed faster development with increasing temperature.Daily food consumption rate was highest at the highest temperature. The combined effects of temperature and food availability on survival were investigated for the same four temperatures and three different feed concentrations.Only food availability affected the mortality rate, with the

Heat stress does not induce wasting symptoms in the giant California sea cucumber (Apostichopus californicus)

“…Unlike stiffening behaviour, we did not observe any significant trends in spawning behaviour or evisceration. Of the 11 spawning events, 9 occurred in elevated-temperature treatments (warm or heat wave) and this trend, although insignificant, was expected as stress spawning has been previously reported in other sea cucumber species (Battaglene et al, 2002; Rakaj et al, 2018; Schagerström et al, 2021). We were unable to associate spawning with individual phenotypes due to the co-housing experimental design.…”

Effect of live-storage period and temperature on oxygen consumption rate in the cold-water sea cucumber Parastichopus tremulus

“…Since it is documented that individuals also occur at shallow depths up to 18 m (Ludwig, 1900), one could expect P. tremulus to be well adapted to a wide range of temperatures. Based on observations from the Gullmar Fjord, Schagerström et al (2022) speculated that shallow areas (25-35 m) are visited in connection with spawning, potentially adding a seasonal component to the species`general temperature tolerance level. To identify temperature thresholds and the optimal range with respect to seasonal requirements is not just of great importance from a conservational standpoint, but also key for handling, holding, and rearing of a species with future economic potential.…”

“…In order to enable the preservation of our coastal marine environment and an effective management of the marine resources, we urgently need to learn more about the species`basic physiological operating principles and responses to its specific environment. Furthermore, it is requisite to determine the species`environmental requirements for development, growth, and welfare in captivity, considering its potential as an aquaculture candidate (Landes et al, 2019;Schagerström et al, 2022). However, it should be noted that the conditions conducive to growth in aquaculture may differ substantially from those in the natural habitat.…”

Hatchery-Imposed Selection Does Not Impact the Genetic Diversity of Australian Farmed Blue Mussels (Mytilus spp.)

“…Mass spawning is unpredictable and can result in the domination of certain family lineages [13,52]. Induced spawning has been seen to improve reproductive success and decrease the risk of inbreeding and genetic bottleneck [13,52,63,64].…”