Mucus as a mediator of gametogenic synchrony in the sea cucumber Cucumaria frondosa (Holothuroidea: Echinodermata)

Abstract

The data presented here demonstrate that the sea cucumber Cucumaria frondosa secretes a biologically active mucus that helps maintain gametogenic synchrony among conspecifics. Either a whole mature individual or a sample of its freshly collected mucus was able to initiate gametogenesis in conspecifics that were in the gametogenic recovery stage when other environmental conditions, including daylength, were maintained constant. Similar results were obtained when the mucus was kept in seawater for less than 3 h prior to its use, whereas after 6 h in seawater, the mucus had lost its inducing properties. Laboratory experiments showed that the mucus was produced in lesser amount during late summer and autumn; the production rapidly increased in early January to reach a peak a few months before the June spawning, in 1992 and 1993. The increment of mucus production was concurrent with the initiation of gametogenesis. Synthesis of mucus was maximal in individuals having attained gametogenic maturity and minimum in individuals with less developed gonads. At first relatively stable in seawater, the mucus gradually lost its integrity within a period of 3–5 h, suggesting that the mucus may be carried over long distances by currents, thus allowing a transfer of information before its complete degradation. This phenomenon was observed in the field where streams of mucus could be followed by SCUBA divers as far as 20–30 m away from the secreting animal. The data presented here are the first evidence of the important role played by mucus secretion during the gametogenic processes of an echinoderm.

Temporal variations in fatty acid composition of deep-sea holothurians: evidence of bentho-pelagic coupling

“…The importance of PUFAs in reproduction and development, and particularly for early life stages of marine invertebrates (Pond et al 1996, Albessard et al 2001, may be as crucial as reproductively important carotenoids found within the same holothurian species investigated in this study (Hudson et al 2003, Wigham et al 2003b, Hudson 2004, and in other shallow-water holothurians (Matsuno & Tsushima 1995, Hamel & Mercier 1999. Amperima rosea is the most abundant holothurian species on the PAP, following a massive population boom in 1997 (Billett et al 2001, Wigham 2002.…”

In vivo investigation of oocyte transit and maturation in a broadcast‐spawning holothurian

“…The in vivo surgical methods described above are similar to previously used techniques that were shown to have no significant impact on the behavior and general health of the animals (Hamel & Mercier 1996b, 1999). Indeed, holothurians are generally very resilient; many of them use evisceration as a defense mechanism, and a high rate of organ regeneration is recorded in most species (reviewed by Garcia‐Arraras & Greenberg 2001).…”

Reserve site selection for data‐poor invertebrate fisheries using patch scale and dispersal dynamics: a case study of sea cucumber(Cucumaria frondosa)

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