Bio 515
Factors That Influence the Reproduction of Sea Cucumbers by Angela Mackey (Biol 515 at SDSU, Fall 2001)
Copyright © 2002 by Angela Mackey and Brian T. Hentschel (hentsche@sunstroke.sdsu.edu)
INTRODUCTION The echinoderm class Holothuroidea consists of sea cucumbers, which can be described as worm-like organisms with elongated, soft bodies. Like most echinoderms, holothuroids have 5 rows of tube feet along their bodies. These tube feet aid the animal in attachment, locomotion and respiration (Pearse et al. 1987). Within the class Holothuroidea, there are about 1250 species, and these are distributed among 200 genera (Smiley et al. 1991). There is much variety among the habitats in which sea cucumbers reside. Some species, like Cucumaria fallax, inhabit quiet, still waters, while others, such as C. miniata, are found in areas that are constantly swept by tidal currents (McEuen 1988). Some holothuroids are tropical reef dwellers (Uthicke 1997); others live in temperate or polar waters (Hamel and Mercier 1995). Even the depth at which these animals can be found varies greatly. Many species live within the intertidal zone, but a few sea cucumbers live deep in the ocean, some among hydrothermal vents (Smirnov et al. 2000). Regardless of the environment in which they are found, sea cucumbers have become highly adapted to life in that environment, especially in their reproductive cycles. Sea cucumbers can reproduce through sexual reproduction as well as asexual reproduction. Each mode of reproduction has several environmental factors that have been proposed to control its timing. This paper will first introduce the two types of reproduction found in sea cucumbers. I will then discuss some of the factors that have been shown to regulate sexual reproduction, specifically the processes of gametogenesis and spawning, and the factors assumed to control asexual reproduction. Finally, I will make a few suggestions as to directions that should be taken during future studies on
Copyright © 2002 by Angela Mackey and Brian T. Hentschel (hentsche@sunstroke.sdsu.edu)
INTRODUCTION The echinoderm class Holothuroidea consists of sea cucumbers, which can be described as worm-like organisms with elongated, soft bodies. Like most echinoderms, holothuroids have 5 rows of tube feet along their bodies. These tube feet aid the animal in attachment, locomotion and respiration (Pearse et al. 1987). Within the class Holothuroidea, there are about 1250 species, and these are distributed among 200 genera (Smiley et al. 1991). There is much variety among the habitats in which sea cucumbers reside. Some species, like Cucumaria fallax, inhabit quiet, still waters, while others, such as C. miniata, are found in areas that are constantly swept by tidal currents (McEuen 1988). Some holothuroids are tropical reef dwellers (Uthicke 1997); others live in temperate or polar waters (Hamel and Mercier 1995). Even the depth at which these animals can be found varies greatly. Many species live within the intertidal zone, but a few sea cucumbers live deep in the ocean, some among hydrothermal vents (Smirnov et al. 2000). Regardless of the environment in which they are found, sea cucumbers have become highly adapted to life in that environment, especially in their reproductive cycles. Sea cucumbers can reproduce through sexual reproduction as well as asexual reproduction. Each mode of reproduction has several environmental factors that have been proposed to control its timing. This paper will first introduce the two types of reproduction found in sea cucumbers. I will then discuss some of the factors that have been shown to regulate sexual reproduction, specifically the processes of gametogenesis and spawning, and the factors assumed to control asexual reproduction. Finally, I will make a few suggestions as to directions that should be taken during future studies on
Cited: Babcock, R., C. Mundy, J. Keesing and J. Oliver. 1992. Predictable and unpredictable spawning events: in situ behavioural data from free-spawning coral reef invertebrates. Invertebrate Reproduction and Development 22:213-228. Bay-Schmith, E. and J.S. Pearse. 1987. Effect of fixed daylengths on the photoperiodic regulation of gametogenesis in the sea urchin Strongylocentrotus purpuratus. International Journal of Invertebrate Reproduction and Development 11:287-294. Cameron, J. L. and P. V. Fankboner. 1986. Reproductive biology of the commercial sea cucumber Parastichopus califonicus (Stimpson) (Echinodermata: Holothuroidea) I. Reproductive periodicity and spawning behavior. Canadian Journal of Zoology 64:168-175. Chao, S.-M., C.-P. Chen and P. S. Alexander. 1994. Reproduction and growth of Holothuria atra (Echinodermata: Holothuroidea) at two contrasting sites in southern Taiwan. Marine Biology 119:565-570. Conand, C. 1993. Reproductive biology of the holothurians from the major communities of the New Caledonian Lagoon. Marine Biology 116:439-450. Costelloe, J. 1985. The annual reproductive cycle of the holothurian Aslia lefevrei (Dendrochirota: Echinodermata). Marine Biology 88:155-165. Crozier, W. J. 1917. Multiplication by fission in Holothurians. American Naturalist 51:560-566. Emson, R. H. and P. V. Mladenov. 1987. Studies of the fissiparous holothurian Holothuria parvula (Selenka) (Echinodermata: Holothuroidea). Journal of Experimental Marine Biology and Ecology 111:195-211. Hamel, J.-F., J. H. Himmelman and L. Dufresne. 1993. Gametogenesis and spawning of the sea cucumber Psolus fabricii (Duben and Koren). Biological Bulletin 184:125-143. Hamel, J.-F. and A. Mercier. 1995. Spawning of the sea cucumber Cucumaria frondosa in the St. Lawrence Estuary, eastern Canada. SPC Beche-de-mer Information Bulletin 7:12-18. Hamel, J.-F. and A. Mercier. 1996. Evidence of chemical communication during the gametogenesis of holothuroids. Ecology 77:1600-1616. Angela Mackey: Factors That Influence the Reproduction of Sea Cucumbers p. 7 of 8. Hamel, J.-F. and A. Mercier. 1999. Mucus as a mediator of gametogenic synchrony in the sea cucumber Cucumaria frondosa (Holothuroidea: Echinodermata). Journal of the Marine Biological Association of the United Kingdom 79:121-129. Himmelman, J. H. 1975. Phytoplankton as a stimulus for spawning in three marine invertebrates. Journal of Experimental Marine Biology and Ecology 20:199-214. Kubota, T. and M. Tomari. 1998. Reproduction in the apodid sea cucumber Polycheira rufescens: semilunar spawning rhythm and sex change. Journal of the Marine Biological Association of the United Kingdom 78:249-267. McEuen, F. S. 1988. Spawning behaviors of northeast Pacific sea cucumbers (Holothuroidea: Echinodermata). Marine Biology 98:565-585. Morgan, A. D. 2000. Induction of spawning in the sea cucumber Holothuria scabra (Echinodermata: Holothuroidea). Journal of the World Aquaculture Society 31: 186-194. Pearse, V., J. Pearse, M. Buchsbaum and R. Buchsbaum. 1987. Living Invertebrates. Boxwood Press, Pacific Grove, California, USA. Purcell, S., D. Gardner and J. Bell. 2002. Developing optimal strategies for restocking sandfish: a collaborative project in New Caledonia. SPC Beche-de-mer Information Bulletin 16:1-4. Randall, D., W. Burggren and D. French. 1997. Eckert Animal Physiology. W.H. Freeman and Company, New York, USA. Roberts, D. and H.M. Moore. 1997. Tentacular diversity in deep-sea deposit-feeding holothurians: Implications for biodiversity in the deep sea. Biodiversity and Conservation 6:1487-1505. Smiley, S., F. S. McEuen, C. Chaffee and S. Krishan. 1991. Echinodermata: Holothuroidea. Pages 663-750 in A.C. Giese, J. S. Pearse, and V. B. Pearse, editors. Reproduction of marine invertebrates, echinodermata and lophophorates. Volume VI. Boxwood Press, Pacific Grove, California, USA. Smirnov, A.V., A.V Gebruk. S.V. Galkin and T. Shank. 2000. New species of holothurian (Echinodermata: Holothuroidea) from hydrothermal vent habitats. Journal of the Marine Biological Association of the United Kingdom 80:321-328. Tanaka, Y. 1958. Seasonal changes occurring in the gonad of Stichopus japonicus. Bulletin of the Faculty of Fisheries, Hokkaido University 9:29-36. Thandar, A.S. 1998. A new genus and three new species of deep-sea holothuroids from the west coast of South Africa (Echinodermata). Journal of Zoology 244:79-88. Uthicke, S. 1997. Seasonality of asexual reproduction in Holothuria (Halodeima) atra, H. (H.) edulis and Stichopus chloronotus (Holothuroidea: Aspidochirotida) on the Great Barrier Reef. Marine Biology 129:435-441. Uthicke, S. 2001. Influence of asexual reproduction on the structure and dynamics of Holothuria (Halodeima) atra and Stichopus chloronotus populations of the Great Barrier Reef. Marine and Freshwater Research 52:205-215. Young, R.T. 1945. Stimulation of spawning in the mussel (Mytilys californianus). Ecology 26:58-69. Angela Mackey: Factors That Influence the Reproduction of Sea Cucumbers p. 8 of 8.