Open Access Open Access  Restricted Access Subscription Access

Observations of Synchronized Spawning, Larval Survival and Settlement in Corals of the Genus Acropora in Lakshadweep, India


Affiliations
1 Zoological Survey of India, Marine Regional Centre, Chennai 600 028, India
 

Reports of synchronous spawning in corals of Lak-shadweep reefs, India have been purely anecdotal. To understand factors that underlie coral spawning in Lakshadweep, we studied four Acropora species (A. muricata, A. cytherea, A. hemprichii and A. nobilis) in Kavaratti atoll from February to March 2018. These species were observed in situ for oocyte maturation, and the larvae of species A. muricata and A. cytherea were assessed for survival and settlement rates. Observations on oocyte maturation indicated possible spawning closer to the immediate full moon of species in which 7–28 % of the colonies had mature oocytes. Thus, A. muricata, A. cytherea and A. hemprichii spawned on 25 and 26 February 2018, demonstrating multi-specific synchronous spawning, whereas A. nobilis spawned on 21 March 2018. Larval survival rates revealed a steep die-off beginning on day 12 post-spawning and maximum survival up to 24–27 days. Settlement occurred between 12 and 20 days for A. muricata and between 12 and 22 days for A. cytherea. The comparatively low survival duration and fewer larvae surviving for settlement show that maximum settlement could be heavily compromised. However, the study reveals that the comparatively late onset of settlement (from day-12, post-spawning) and the broader settlement window of 8–10 days could allow room for long-distance dispersal of larvae. Further studies on this front are required to gather a better picture.

Keywords

Acropora Genus, Coral Reproduction, Larvae Survival, Oocyte Maturation, Synchronized Spawning.
User
Notifications
Font Size

  • Harrison, P. L., Babcock, R. C., Bull, G. D., Oliver, J. K., Wallace, C. C. and Willis, B. L., Mass spawning in tropical reef corals. Science, 1984, 223(4641), 1186–1189.
  • Babcock, R. C., Bull, G. D., Harrison, P. L., Heyward, A. J., Oliver, J. K., Wallace, C. C. and Willis, B. L., Synchronous spawnings of 105 scleractinian coral species on the Great Barrier Reef. Mar. Biol., 1986, 90(3), 379–394.
  • Guest, J. R., Baird, A. H., Clifton, K. E. and Heyward, A. J., From molecules to moonbeams: spawning synchrony in coral reef organisms. Invertebr. Reprod. Dev., 2008, 51(3), 145–149.
  • Oliver, J. K., Babcock, R. C., Harrison, P. L. and Willis, B. L., Geographic extent of mass coral spawning: clues to ultimate causal factors. In Proceedings of the Sixth International Coral Reef Symposium, Townsville, Australia, 8–12 August 1988.
  • Baird, A. H., The ecology of coral larvae: settlement patterns, habitat selection and the length of the larval phase. Ph D dissertation, James Cook University, Townsville, Australia, 2001, pp. 107–153.
  • Harrison, P. L. and Wallace, C. C., Reproduction, dispersal and recruitment of scleractinian corals. In Ecosystems of the World: Coral Reefs (ed. Dubinsky, Z.), Elsevier, Amsterdam, 1990, pp. 133–207.
  • Willis, B. L., Babcock, R. C., Harrison, P. L., Oliver, J. K. and Wallace, C. C., Patterns in the mass spawning of corals on the Great Barrier Reef from 1981 to 1984. In Proceedings of the Fifth International Coral Reef Congress, Tahiti, French Polynesia, 1985.
  • Howells, E. J., Abrego, D., Vaughan, G. O. and Burt, J. A., Coral spawning in the Gulf of Oman and relationship to latitudinal variation in spawning season in the northwest Indian Ocean. Sci. Rep., 2014, 4(1), 1–6.
  • Harrison, P. L., Sexual reproduction of scleractinian corals. In Coral Reefs: An Ecosystem in Transition, Part 3 (eds Dubinsky, Z. and Stambler, N.), Springer, Berlin, Germany, 2011, pp. 59–85.
  • Baird, A. H., Marshall, P. A. and Wolstenholme, J., Latitudinal variation in the reproduction of Acropora in the Coral Sea. In Proceedings of the 9th International Coral Reef Symposium, Bali, Indonesia, 2002.
  • Gilmour, J., Speed, C. W. and Babcock, R., Coral reproduction in Western Australia. PeerJ, 2016, 4, e2010.
  • Mendes, J. M. and Woodley, J. D., Timing of reproduction in Montastraea annularis: relationship to environmental variables. Mar. Ecol. Prog. Ser., 2002, 227, 241–251.
  • SAC, Coral Reef Atlas of the World, Vol. I. Central Indian Ocean, Ahmedabad, 2010, pp. 63–63.
  • Guest, J., Heyward, A., Omori, M., Iwao, K., Morse, A. and Boch, C., Rearing coral larvae for reef rehabilitation. In Reef Rehabilitation Manual (ed. Edwards, A. J.), Coral Reef Targeted Research and Capacity Building for Management Program, St Lucia, Australia, 2010, pp. 73–98.
  • Rare phenomenon on the sea. The Hindu, New Delhi, 27 March 2013; https://www.thehindu.com/sci-tech/energy-and-environment/a-rare-phenomenon-on-the-sea/article4551858.ece (accessed on 23 October 2020).
  • Hayashibara, T., Ohike, S. and Kakinuma, Y., Embryonic and larval development and planula metamorphosis of four gametespawning Acropora (Anthozoa, Scleractinia). In Proceedings of the 8th International Coral Reef Symposium, Panama, 1997.
  • Wallace, C. C., Reproduction, recruitment and fragmentation in nine sympatric species of the coral genus Acropora. Mar. Biol. 1985, 88(3), 217–233.
  • Richmond, R. H., Reproduction and recruitment in corals: critical links in the persistence of reefs. In Life and Death of Coral Reefs (ed. Birkeland, C.), Chapman and Hall Publishers, New York, USA, 1997, pp. 175–197.
  • Heyward, A. J. and Negri, A. P., Natural inducers for coral larval metamorphosis. Coral Reefs, 1999, 18(3), 273–279.
  • Harrington, L., Fabricius, K., De’Ath, G. and Negri, A., Recognition and selection of settlement substrata determine postsettlement survival in corals. Ecology, 2004, 85, 3428–3437.
  • Tebben, J. et al., Chemical mediation of coral larval settlement by crustose coralline algae. Sci. Rep., 2015, 5(1), 1–1.
  • Pollock, F. J. et al., Coral larvae for restoration and research: a large-scale method for rearing Acropora millepora larvae, inducing settlement, and establishing symbiosis. PeerJ, 2017, 5, e3732.
  • Raj, K. D. and Edward, J. K. P., Observations on the reproduction of Acropora corals along the Tuticorin coast of the Gulf of Mannar, southeastern India. Indian J. Geomar. Sci., 2010, 39(2), 219–226.
  • Mustafa, A. M. and Silva, M. C. D., Sex and spawning of corals at Port Blair. Islands on March, 1991, 3, 69–70.
  • Boch, C. A., Ananthasubramaniam, B., Sweeney, A. M., Doyle, F. J. and Morse, D. E., Effects of light dynamics on coral spawning synchrony. Biol. Bull., 2011, 220(3), 161–173.
  • Jokiel, P. L., Ito, R. Y. and Liu, P. M., Night irradiance and synchronization of lunar release of planula larvae in the reef coral Pocillopora damicornis. Mar. Biol., 1985, 88(2), 167–174.
  • Hayashibara, T. et al., Patterns of coral spawning at Akajima Island Okinawa, Japan. Mar. Ecol. Prog. Ser., 1993, 25, 253–262.
  • Nozawa, Y. and Harrison, P. L., Effects of elevated temperature on larval settlement and post-settlement survival in scleractinian corals, Acropora solitaryensis and Favites chinensis. Mar. Biol., 2007, 152(5), 1181–1185.
  • https://www.ospo.noaa.gov/data/sst/anomaly/2018 (accessed on 8 December 2018).

Abstract Views: 391

PDF Views: 130




  • Observations of Synchronized Spawning, Larval Survival and Settlement in Corals of the Genus Acropora in Lakshadweep, India

Abstract Views: 391  |  PDF Views: 130

Authors

S. Nina Tabitha
Zoological Survey of India, Marine Regional Centre, Chennai 600 028, India
Kevin Shimrone Moses
Zoological Survey of India, Marine Regional Centre, Chennai 600 028, India
Rajkumar Rajan
Zoological Survey of India, Marine Regional Centre, Chennai 600 028, India

Abstract


Reports of synchronous spawning in corals of Lak-shadweep reefs, India have been purely anecdotal. To understand factors that underlie coral spawning in Lakshadweep, we studied four Acropora species (A. muricata, A. cytherea, A. hemprichii and A. nobilis) in Kavaratti atoll from February to March 2018. These species were observed in situ for oocyte maturation, and the larvae of species A. muricata and A. cytherea were assessed for survival and settlement rates. Observations on oocyte maturation indicated possible spawning closer to the immediate full moon of species in which 7–28 % of the colonies had mature oocytes. Thus, A. muricata, A. cytherea and A. hemprichii spawned on 25 and 26 February 2018, demonstrating multi-specific synchronous spawning, whereas A. nobilis spawned on 21 March 2018. Larval survival rates revealed a steep die-off beginning on day 12 post-spawning and maximum survival up to 24–27 days. Settlement occurred between 12 and 20 days for A. muricata and between 12 and 22 days for A. cytherea. The comparatively low survival duration and fewer larvae surviving for settlement show that maximum settlement could be heavily compromised. However, the study reveals that the comparatively late onset of settlement (from day-12, post-spawning) and the broader settlement window of 8–10 days could allow room for long-distance dispersal of larvae. Further studies on this front are required to gather a better picture.

Keywords


Acropora Genus, Coral Reproduction, Larvae Survival, Oocyte Maturation, Synchronized Spawning.

References





DOI: https://doi.org/10.18520/cs%2Fv121%2Fi1%2F133-140