Density, diversity, and survival of juvenile corals on reefs of Zanzibar, Tanzania

Volume 7, Issue 1, February 2023     |     PP. 1-23      |     PDF (1072 K)    |     Pub. Date: February 8, 2023
DOI: 10.54647/geosciences170235    82 Downloads     44802 Views  

Author(s)

Ali M. Ussi, The State University of Zanzibar, Box 146, Zanzibar, Tanzania
Christopher A. Muhando, Institute of Marine Sciences, Box 668, Zanzibar, Tanzania
Robert van Woesik, Department of Ocean Engineering and Marine Sciences, Florida Institute of Technology, 150 West University Blvd, Melbourne, Florida 32901, USA

Abstract
The sustainability of coral populations depends on the steady supply of sexually produced offspring, especially as coral populations attempt to adjust to climate change. Therefore, information on the density, diversity, and survival of juvenile corals is vital for predicting recruitment success and determining the trajectories of coral populations. This study investigated the dynamics of juvenile corals in Zanzibar in three habitats (reef flat, reef crest, and reef slope) and at three sites (Chumbe, Chunguu, and Mnemba) from November 2010 to May 2012. In total, 10,932 juvenile corals were recorded, which belonged to 13 coral families and 38 coral genera. The mean density of juvenile colonies ranged from 10.3 ± 0.8 to 16.4 ± 1.3 colonies per m2. Among the coral genera recorded, Acropora and Porites were the most prolific. Survival of juvenile corals was high at all three sites, between 60−78%, with the highest survival on the reef slopes of Chumbe. There were significant seasonal differences in juvenile coral survival rates, with the highest survival occurring during the northeastern monsoon. On the western coast, at Chumbe, the co-occurrence of juvenile and adult Acropora implies that self-seeding is occurring. In contrast, the lack of Acropora adults at Chunguu suggests that the site receives recruits from other reefs. On the eastern coast, Mnemba had the lowest survival rates of all three sites, supporting mainly faviids and massive Porites. The results suggest that the western reefs have a more significant potential to recover from disturbances than the eastern reefs.

Keywords
Juvenile corals, density, diversity, survival, Zanzibar, Tanzania.

Cite this paper
Ali M. Ussi, Christopher A. Muhando, Robert van Woesik, Density, diversity, and survival of juvenile corals on reefs of Zanzibar, Tanzania , SCIREA Journal of Geosciences. Volume 7, Issue 1, February 2023 | PP. 1-23. 10.54647/geosciences170235

References

[ 1 ] Adjeroud, M., Michonneau, F., Edmunds, P., Chancerelle, Y., Lison de Loma, T., Penin, L., Thibaut, L., Vidal-Dupiol, J., Salvat, B., and Galzin, R. (2009). Recurrent disturbances, recovery trajectories, and resilience of coral assemblages on a South Central Pacific reef. Coral Reefs, 28: 775–780
[ 2 ] Amar, K. O., Chadwick, N. E. and Rinkevich, B. (2007). Coral planulae as dispersion vehicles: biological properties of larvae released early and late in the season. Marine Ecology Progress Series, 350: 71-78.
[ 3 ] Baird, A. H. and Hughes, T. P. (2000). Competitive dominance by tubular corals. An experimental analysis of recruitment and survival of understory assemblages. Journal of Experimental Marine Biology and Ecology, 251:117-132.
[ 4 ] Bak, R. P. M. and Engel, M. S. (1979). Distribution, abundance and survival of juvenile hermatypic corals (Scleractinia) and the importance of life history strategies in the parent coral community. Marine Biology, 54(4): 341-352.
[ 5 ] Banks, S. A. and Harriott, V. J. (1996). Patterns of coral recruitment at the Gneering Shoals, southeast Queensland, Australia. Coral Reefs, 15: 225-230.
[ 6 ] Bassim, K. and Sammarco, P. (2003). Effects of temperature and ammonium on larval development and survivorship in a scleractinian coral (Diploria strigosa). Marine Biology, 142(2): 241-252.
[ 7 ] Bergman, K. C. and Öhman, M. C. (2001). Coral reef community structure in Zanzibar, Tanzania. In Richmond, M. D. and J. Francis (eds), Marine Science Development in Tanzania and Eastern Africa. Proc. 20th Anniversary Conference on Advances in Marine Science in Tanzania: 263–275.
[ 8 ] Birrell, C. L., MacCook, L. J. and Willis, B. L. (2005). Effects of algal turfs and sediments on coral settlement. Marine Pollution Bulletin, 41: 404-414.
[ 9 ] Box, J. B. and Mumby, P. J. (2007). Effect of macroalgal competition on growth and survival of juvenile Caribbean corals. Marine Ecology Progress Series, 342: 139–149.
[ 10 ] Bronstein, O. and Loya, Y. (2014). Echinoid community structure and rates of herbivory and bioerosion on exposed and sheltered reefs. Journal of Experimental Marine Biology and Ecology, 456: 8-17.
[ 11 ] Cowen, R. K. and Sponaugle, S. (2009). Larval dispersal and marine population connectivity. Annual Review of Marine Science, 1:443–66.
[ 12 ] Done, T. J. (1992). Phase shifts in coral reef communities and their ecological significance. Hydrobiologia, 247: 121-132.
[ 13 ] Edmunds, P. (2007). Evidence for a decadal-scale decline in the growth rates of juvenile scleractinian corals. Marine Ecology Progress Series, 341, 1-13.
[ 14 ] English, S., Wilkinson, C., and Baker, V. (1994). Survey Manual for Tropical Marine Resources, 2nd Edition. Australian Institute of Marine Science, Townsville. 368pp.
[ 15 ] Fabricius, K. E. (2005). Effects of terrestrial run-off on the ecology of corals and coral reefs: review and synthesis. Marine Pollution Bulletin, 50: 125-146.
[ 16 ] Fox, H. E. (2004). Coral recruitment in blasted and unblasted sites in Indonesia: Assessing rehabilitation potential. Marine Ecology Progress Series, 269: 131-139
[ 17 ] Gilmour, J. (1999). Experimental investigation into the effects of suspended sediment on fertilisation, larval survival and settlement in a scleractinian coral. Marine Biology, 135(3): 451-462.
[ 18 ] Glynn, P.W. and Weerdt, W.H. (1991). Elimination of two reef building hydrocorals following the 1982-83 El Niño warming event. Science, 253: 69-71.
[ 19 ] Gross, E. M. (2003). Allelopathy of aquatic autotrophs. Critical Reviews in Plant Sciences, 22(3-4): 313-339.
[ 20 ] Harriott, V. J. and Fisk, D. A. (1988). Recruitment patterns of three corals: a study of three reefs. Australian Journal of Marine and Freshwater Research, 39 (4): 409-416.
[ 21 ] Harrison, P. L. (2011). Sexual reproduction of scleractinian corals. In: Dubinsky Z, Stambler N (eds) Coral reefs: an ecosystem in transition. Springer, Berlin, pp 59–85
[ 22 ] Hughes, T. P., Baird, A. H., Bellwood, D. R., Card, M., Connolly, S. R., Folke, C., Grosberg, R., Hoegh-Guldberg, O, Jackson, J. B. C, Kleypas, J., Lough, J. M., Marshall, P., Nystro¨m, M., Palumbi, S. R, Pandolfi, J. M, Rosen, B. and Roughgarden, J. (2003). Climate change, human impacts, and the resilience of coral reefs. Science, 301(5635): 929-933.
[ 23 ] Hughes, T. P., Baird, A. H., Dinsdale, E. A., Moltschaniwskyj, N. A., Pratchett, M. S., Tanner, J. E. and Willis, B. L. (2000). Supply-side ecology works both ways: the link between benthic adults, fecundity, and larval recruits. Ecology, 81(8): 2241-2249.
[ 24 ] Hughes, T. P., Baird, A. H., Dinsdale, E. A., Moltschaniwskyj, N. A., Pratchett, M. S., Tanner, J. E. and Willis, B. L. (1999). Patterns of recruitment and abundance of corals along the Great Barrier Reef. Nature, 397(6714): 59-63.
[ 25 ] Hughes, T. P., Graham, N. A. J., Jackson, J. B. C., Mumby, P. J. and Steneck, R. S. (2010) Rising to the challenge of sustaining coral reef resilience. Trends Ecology Evolution, 25:633–642
[ 26 ] Karisa, J. F., Kaunda-Arara, B., and Obura, D. O. (2008). Spatial and temporal variation in coral recruitment and mortality in coastal Kenya. In Obura, D.O., Tamelander, J. and Linden, O. (Eds) (2008). Ten years after bleaching - facing the consequences of climate change in the Indian Ocean. CORDIO Status Report 2008. Coastal Oceans Research and Development in the Indian Ocean/Sida-SAREC. Mombasa. 4: 223-233.
[ 27 ] Kuffner, I. B., Walters, L. J., Becerro, M. A., Paul, V. J., Ritson-Williams, R. and Beach, K. S. (2006). Inhibition of coral recruitment by macroalgae and cyanobacteria. Marine Ecology Progress Series, 323: 107-117.
[ 28 ] Larcombe, P., Ridd, V. P., Prytz, A. and Wilson, B. (1995). Factors controlling suspended sediments on inner-shelf coral reef. Coral Reefs, 14: 163-171.
[ 29 ] Loya, Y., Sakai, K., Yamazato, K., Nakano, Y., Sambali, H. and van Woesik, R. (2001). Coral bleaching the winners and the losers. Ecology Letters 4, 122-131.
[ 30 ] Mbije, N. E., Wagner, G. M., Francis, J., Ohman, M. C. and Garpe, K. (2002). Patterns in the distribution and abundance of hard corals around Zanzibar Island. Ambio, 31 (7-8): 609-611.
[ 31 ] McCook, L., Jompa, J. and Diaz-Pulido, G. (2001). Competition between corals and algae on coral reefs: a review of evidence and mechanisms. Coral Reefs, 19(4): 400-417.
[ 32 ] Miller, J., Muller, E., Rogers, C., et al., 2009. Coral disease following massive bleaching in 2005 causes 60% decline in coral cover on reefs in the US Virgin Islands. Coral Reefs 28, 925–937
[ 33 ] Muhando, C. A. (2003). Enhanced coral larval settlement and coral transplantation as means of promoting coral replenishment in Tanzania. Ph.D thesis, University of Dar es Salaam. 285pp.
[ 34 ] Muhando, C. A. (2009). Calibration of Community-based Coral Reef Monitoring Protocols: Tanzanian Case Study. Western Indian Ocean Journal of Marine Sciences, 9(1): 103 – 114.
[ 35 ] Muhando, C. A. and Lanshammar, F. (2009). Ecological effects of the Crown-of-Thorns Starfish removal programme on Chumbe Island Coral Park, Zanzibar, Tanzania. Proceedings of the 11th International Coral Reefs Symposium, Florida, 2: 1134-1138.
[ 36 ] Muhando, C.A. (2001). The 1998 coral bleaching and mortality event in Tanzania: Implications for coral reef research and management. In: Richmond, M.D. and Francis, J. (eds.), 2001. Marine science development in Tanzania and Eastern Africa. Proceedings of the 20th anniversary Conference on Advances in Marine Science in Tanzania, 28 June-1 July 1999, Zanzibar, Tanzania. IMS/WIOMSA, 329-342 pp.
[ 37 ] Muller, J. M., Muller, E., Rogers, C., Waara, R., Atkinson, A., Whelan, M., Patterson, M. and Witcher, B. (2009). Coral disease following massive bleaching in 2005 causes 60 % decline in coral cover on reefs in the US Virgin Islands. Coral Reefs, 98: 925–937.
[ 38 ] Mundy, C and Babcock, R. (1996). Coral recruitment: consequences of settlement choice for early growth and survivorship in two scleractinians. Journal of Experimental Marine Biology and Ecology, 206: 179-201.
[ 39 ] Muzuka, A. N., Dubi, A. M., Muhando, C. A. and Shaghude, Y. W. (2010). Impact of hydrographic parameters and seasonal variation in sediment fluxes on coral status at Chumbe and Bawe reefs, Zanzibar, Tanzania. Estuarine, Coastal and Shelf Science, 30: 1-8.
[ 40 ] Mwaipopo, O. U. (1990). Oceanographic study for Unguja and Mnemba Islands. In: Ngoile, M.A.K. ed. Ecological Baseline Surveys of Coral Reefs and Intertidal Zones around Mnemba Island and Zanzibar Town. Zanzibar Environmental Study Series no. 8.
[ 41 ] Nozawa Y, Harrison P (2007) Effects of elevated temperature on larval settlement and post-settlement survival in scleractinian corals, Acropora solitaryensis and Favites chinensis. Marine Biology, 152:1181–1185
[ 42 ] Nzali, M., Johnstone, R. W. and Mgaya, Y. D. (1998). Factors affecting scleractinian coral recruitment on a nearshore reef in Tanzania. Ambio, 27: 717- 722.
[ 43 ] O’Leary J. K., Potts D, Schoenrock, K. M, and McClanahan, T. R. (2013). Fish and sea urchin grazing opens settlement space equally but urchins reduce survival of coral recruits. Marine Ecology Progress Series, 493:165–177
[ 44 ] Obura, D., Church, J., Daniels, C., Kalombo, H., Schleyer, M. and Suleiman, M. (2004). Status of Coral Reefs in East Africa; Kenya, Tanzania, Mozambique and South Africa. In: Wilkinson, C. (2004). Status of Coral reefs of the World. Australian Institute of Marine Science. Townsville.378pp.
[ 45 ] Paul, V. J. and Puglisi, M. P. (2004). Chemical mediation of interactions among marine organisms. Natural Product Reports, 21(1): 189-209.
[ 46 ] Penin L, Michonneau F, Carrol A, Adjeroud M (2011) Effects of predator and grazer exclusion on early post-settlement mortality. Hydrobiologia, 663: 259−264.
[ 47 ] Pineda, J., Hare, J. A., Sponaugle, S. (2007). Larval transport and dispersal in the coastal ocean and consequences for population connectivity. Oceanography, 20: 22-39.
[ 48 ] Richmond, R. H. and Hunter, C. L. (1990). Reproduction and Recruitment of Corals: Comparisons among the Caribbean, the Tropical Pacific, and the Red Sea. Marine Ecology Progress Series, 60:185– 203.
[ 49 ] Ritson-Williams, R., Paul, V., Arnold, S. and Steneck, R. (2010). Larval settlement preferences and post-settlement survival of the threatened Caribbean corals Acropora palmata and A. cervicornis. Coral Reefs, 29(1): 71-81.
[ 50 ] Ruiz-Zárate, M. A., Espinoza-Avalos, J., Carricart-Ganivet, J. P. and Fragoso, D. (2000). Relationships between Manicina areolata (Cnidaria: Scleractinia), Thalassia testudinum (Anthophyta) and Neogoniolithon sp (Rhodophyta). Marine Ecology Progress Series, 206: 135-146.
[ 51 ] Sale, P. F., Van Lavieren, H., Lagman, M. A., Atema, J., Butler, M., Fauvelot, C., Hogan, J. D., Jones, G. P., Lindeman, K. C., Paris, C. B., Steneck, R and Stewart, H. L. (2010). Preserving reef connectivity: A handbook for marine protected area managers. Connectivity Working Group. Coral Reef Targeted Research and Capacity Building for Management Program UNU-INWEH. Melbourne, Australia.
[ 52 ] Sammarco, P. (1982). Echinoid grazing as a structuring force in coral communities: whole reef manipulations. Journal of Experimental Marine Biology and Ecology, 61: 31-55.
[ 53 ] Sammarco, P. W. and Andrews, J. C. (1989). The Helix experiment: Differential localized dispersal and recruitment patterns in Great Barrier Reef corals. Limnology and Oceanography, 34(5): 896-912.
[ 54 ] Sammarco, P.W. (1980). Diadema and its relationship to coral spat mortality: grazing, competition and biological disturbance. Journal of Experimental Marine Biology and Ecology, 45: 245-272.
[ 55 ] Schesinger, Y., Goulet, T.L. and Loya, Y., (1998). Reproductive patterns of scleractinian corals in the northern Red Sea. Marine Biology, 132: 691–701
[ 56 ] Sweatman, H., Delean, S. and Syms, C. (2011). Assessing loss of coral cover on Australia’s Great Barrier Reef over two decades, with implications for longer-term trends. Coral Reefs, 30:521–531.
[ 57 ] Tomascik, T. (1991). Settlement patterns of Caribbean scleractinian corals on artificial substrata along a eutrophication gradient, Barbados, West Indies. Marine Ecology Progress Series, 77: 261–269.
[ 58 ] Ussi, A. M. (2009). Population distribution and impacts of Crown-of-Thorns Starfish, Acanthaster planci (L), on some coral reefs of Zanzibar. MSc. Thesis, University of Dar es Salaam. 86pp.
[ 59 ] Ussi, A. M. (2014). Recruitment and growth of scleractinian corals in relation to bio-physical processes in reefs of Unguja island, Zanzibar, Tanzania. Ph.D thesis, University of Dar es Salaam. 245pp.
[ 60 ] van Woesik, R. (2010). Calm before the spawn: global coral spawning patterns are explained by regional wind fields. Proceedings of the Royal Society B: Biological Sciences, 277(1682): 715-722.
[ 61 ] Vermeij, M. J. A., Smith, J. E., Smith, C. M., Thurber, R. V. and Sandin, S. A. (2009). Survival and settlement success of coral planulae: independent and synergistic effects of macroalgae and microbes. Oecologia, 159(2): 325-336.
[ 62 ] Wells, J. W. (1957). Coral reefs. Geological Society of America Memoirs, 67: 609-631.
[ 63 ] Wilkinson, C. (ed.) 2004. Status of Coral Reefs of the World 2004. Australian Institute of Marine Science, Townsville, Australia. 557pp
[ 64 ] Wilkinson, C. (ed.). 2000. Status of Coral Reefs of the World: 2000. Australian Institute of Marine Science, Townsville, Australia. 376pp.