Standard Presentation (12 minutes) Australian Marine Sciences Association 2025 Conference

Does habitat heterogeneity predict high ecological diversity? A case study from Indonesian and Filipino coral reefs (120743)

Cilun Djakiman 1 2 , Morven Rae-Seaman 1 , Fiona Chong 1 , Rebecca Green 3 , Scott Bachmann 4 , Halwi Masdar 5 , Fajrin Rahayaan 2 , Melchor Deocadez 6 , Diana R Bugay 6 , Gino V Limmon 2 7 , Maria Beger 1 8 , Helen Fox 3
  1. School of Biology, University of Leeds, Leeds, United Kingdom
  2. Maritime and Marine Science Center of Excellence, Pattimura University, Ambon, Indonesia
  3. Coral Reef Alliance, San Francisco, Califronia, United States of America
  4. [C]Worthy, Boulder, Colorado, United States of America
  5. Marine Science Department, Hasanuddin University, Makassar, Indonesia
  6. Marine Science Institute, University of the Philippines, Diliman, Quezon City, The Philippines
  7. Faculty of Fisheries and Marine Science, Pattimura University, Ambon, Indonesia
  8. Centre for Biodiversity and Conservation Science , University of Queensland, Brisbane, QLD, Australia

The habitat heterogeneity hypothesis1 suggests that complex habitat arrangements give rise to more ecological niches and thus higher species diversity. Across oceanic basin scales, there is evidence showing that fish and coral diversity can be proxied from high resolution, remotely sensed benthic habitat maps. This is relevant for small-scale reef fishers in Indonesia and the Philippines whose livelihoods are intertwined with and threatened by the climate crisis. Their ability to fish sustainably into the future require practical and adaptable tools. Global-scale satellite derived metrics may be useful products for the identification of areas of high biodiversity and fishery biomass, which may inform the management and use of resilient fishing grounds.

Here, we investigate if metrics of habitat heterogeneity created from fine resolution (5m x 5m) benthic and geomorphic maps can predict ecological diversity at reef scales in the Coral Triangle. Our preliminary results from 15 sites across Ambon-Lease islands in Indonesia demonstrate that high habitat heterogeneity is correlated with high fish and annelid diversity, while medium heterogeneity appears to predict high coral cover. These remote-sensing tools should be further developed as it shows promising utility in the conservation and marine spatial planning of coral reef ecosystems, with broad-scale geographical applicability.

  1. MacArthur R. H. and MacArthur, J. W. (1961). On bird species diversity. Ecology. 42. pp. 594-598