Delineating optimal settlement areas of juvenile reef fish in Ngederrak Reef, Koror state, Republic of Palau
- 220 Downloads
Establishing the effectiveness of habitat features to act as surrogate measures of diversity and abundance of juvenile reef fish provides information that is critical to coral reef management. When accurately set on a broader spatial context, microhabitat information becomes more meaningful and its management application becomes more explicit. The goal of the study is to identify coral reef areas potentially important to juvenile fishes in Ngederrak Reef, Republic of Palau, across different spatial scales. To achieve this, the study requires the accomplishment of the following tasks: (1) structurally differentiate the general microhabitat types using acoustics; (2) quantify microhabitat association with juvenile reef fish community structure; and (3) conduct spatial analysis of the reef-wide data and locate areas optimal for juvenile reef fish settlement. The results strongly suggest the importance of branching structures in determining species count and abundance of juvenile reef fish at the outer reef slope of Ngederrak Reef. In the acoustic map, the accurate delineation of these features allowed us to identify reef areas with the highest potential to harbor a rich aggregation of juvenile reef fish. Using a developed spatial analysis tool that ranks pixel groups based on user-defined parameters, the reef area near the Western channel of Ngederrak is predicted to have the most robust aggregation of juvenile reef fish. The results have important implications not only in management, but also in modeling the impacts of habitat loss on reef fish community. At least for Ngederrak Reef, the results advanced the utility of acoustic systems in predicting spatial distribution of juvenile fish.
KeywordsAcoustics Microhabitat complexity ImageLab Juvenile reef fish
The authors would like to express their gratitude to Dr. Shiela Marcos, Eileen Peñaflor, and David Idip for their invaluable assistance in the conduct of the field work. Funding was provided by the World Bank-Global Environment Facility-Coral Reef Targeted Research-Remote Sensing Working Group, and the Philippine Council for Aquatic and Marine Research and Development.
- Battista, T. A., Costa, B. M., & Anderson, S. M. (2007). Shallow-water benthic habitats of the Republic of Palau (DVD). Silver Spring: NOAA Technical Memorandum NOS NCCOS 59, Biogeography Team.Google Scholar
- Clarke, K. R, & Gorley, R. N. (2006) Primer v6. User manual/tutorial. PRIMER-E:Plymouth PL1 3DH.Google Scholar
- Clarke, K. R, & Warwick, R. M. (2001) Change in marine communities: an approach to statistical analysis and interpretation, 2nd edition. PRIMER-E: Plymouth PL1 3DH.Google Scholar
- English, S., Wilkinson, C., Baker V. (1994). Survey manual for tropical marine resources. ASEAN-Australian Marine Science Project: Living Coastal Resources, Australia 4810: Australian Institute of Marine Science, PMB No. 3, Townsville Mail Centre.Google Scholar
- Hoegh-Guldberg, O., Mumby, P. J., Hooten, A. J., Steneck, R. S., Greenfield, P., Gomez, E. D., Harvell, C. D., Sale, P. F., Edwards, A. J., Caldeira, K., Knowlton, N., Eakin, C. M., Iglesias-Prieto, J., Muthiga, N., Bradbury, R. H., Dubi, A., & Hatziolos, M. E. (2007). Coral reefs under rapid climate change and ocean acidification. Science, 318, 1737–1742.CrossRefGoogle Scholar
- Jackson, J. B. C., Kirby, M. X., Berger, W. H., Bjorndal, K. A., Botsford, L. W., Bourque, B. J., Bradbury, R., Cooke, R., Erlandson, J., Estes, J. A., Hughes, T. P., Kidwell, S., Lange, C. B., Lenihan, H. S., Pandolfi, J. M., Peterson, C. S., Steneck, R. S., Tegner, M. J., & Warner, R. R. (2001). Historical overfishing an the recent collapse of coastal ecosystem. Science, 293, 629–638.CrossRefGoogle Scholar
- Joyce, K. E., Phinn, S. R., Roelfsema, C. M., Neil, D. T., & Dennison, W. T. (2004). Combining Landsat ETM+ and reef check classifications for mapping coral reefs: a critical assessment from the Southern Great Barrier Reef. Australia Coral Reefs, 23, 21–25. doi: 10.1007/s00338-003-0357-7.CrossRefGoogle Scholar
- Kuffner, I. B., Brock, J. C., Grober-Dunsmore, R., Bonito, V. E., Hickey, T. D., & Wright, C. W. (2007). Relationships between reef fish communities and remotely sensed rugosity measurements in Biscayne National Park, Florida, USA. Environmental Biology of Fishes, 78, 71–82. doi: 10.1007/s10641-10006-19078-10644.CrossRefGoogle Scholar
- Mariano, V. (2004) ImageLab: A C++ software package for basic image processing. A Software Project of the Institute of Computer Science, University of the Philippines Los Banos.Google Scholar
- Pitmann, S. J, Christensen, J. D, Caldow, C., Menza, C., Monaco, M. E. (2007) Predictive mapping of fish species richness across shallow-water seascapes in the Caribbean. Ecological Modelling? 4646 doi: 10.1016/j.ecolmodel.2006.12.017.
- Wilson, S. K., Burgess, S. C., Cheal, A. J., Emslie, M., Fisher, R., Miller, I., Polunin, N. V. C., & Sweatman, H. P. A. (2008). Habitat utilization by coral reef fish: implications for specialists vs. generalists in a changing environment. Journal of Animal Ecology, 77, 220–228.CrossRefGoogle Scholar