Identifying Suitable Locations for Mesophotic Hard Corals Offshore of Maui, Hawai'i

PLoS One. 2015 Jul 8;10(7):e0130285. doi: 10.1371/journal.pone.0130285. eCollection 2015.

Abstract

Mesophotic hard corals (MHC) are increasingly threatened by a growing number of anthropogenic stressors, including impacts from fishing, land-based sources of pollution, and ocean acidification. However, little is known about their geographic distributions (particularly around the Pacific islands) because it is logistically challenging and expensive to gather data in the 30 to 150 meter depth range where these organisms typically live. The goal of this study was to begin to fill this knowledge gap by modelling and predicting the spatial distribution of three genera of mesophotic hard corals offshore of Maui in the Main Hawaiian Islands. Maximum Entropy modeling software was used to create separate maps of predicted probability of occurrence and uncertainty for: (1) Leptoseris, (2) Montipora, and (3) Porites. Genera prevalence was derived from the in situ presence/absence data, and used to convert relative habitat suitability to probability of occurrence values. Approximately 1,300 georeferenced records of the occurrence of MHC, and 34 environmental predictors were used to train the model ensembles. Receiver Operating Characteristic (ROC) Area Under the Curve (AUC) values were between 0.89 and 0.97, indicating excellent overall model performance. Mean uncertainty and mean absolute error for the spatial predictions ranged from 0.006% to 0.05% and 3.73% to 17.6%, respectively. Depth, distance from shore, euphotic depth (mean and standard deviation) and sea surface temperature (mean and standard deviation) were identified as the six most influential predictor variables for partitioning habitats among the three genera. MHC were concentrated between Hanaka'ō'ō and Papawai Points offshore of western Maui most likely because this area hosts warmer, clearer and calmer water conditions almost year round. While these predictions helped to fill some knowledge gaps offshore of Maui, many information gaps remain in the Hawaiian Archipelago and Pacific Islands. This approach may be used to identify other potentially suitable areas for MHCs, helping scientists and resource managers prioritize sites, and focus their limited resources on areas that may be of higher scientific or conservation value.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Anthozoa / physiology*
  • Biodiversity
  • Ecology
  • Ecosystem*
  • Geography
  • Hawaii
  • Models, Theoretical
  • Oceans and Seas
  • Pacific Islands
  • ROC Curve
  • Reproducibility of Results
  • Software
  • Species Specificity
  • Temperature

Grants and funding

Funding for this spatial modeling effort was provided by the National Oceanic and Atmospheric Administration’s (NOAA) Office of National Marine Sanctuaries (ONMS) Hawaiian Islands Humpback Whale National Marine Sanctuary (HIHWNMS). This modeling effort was made possible because of research funded by the NOAA’s Office of Marine and Aviation Operations (OMAO) and NOAA’s National Centers for Coastal Ocean Science’s Center for Sponsored Coastal Ocean Research (CSCOR) under award NA07NOS4780188 to the Bishop Museum, NA07NOS4780187 and NA07NOS478190 to the University of Hawai‘i, NA07NOS4780189 to the State of Hawai‘i’s Division of Aquatic Resources and to the NOAA Pacific Islands Fisheries Science Center (PIFSC). Submersible support was provided by the NOAA Undersea Research Program’s Hawai‘i Undersea Research Laboratory under award NA05OAR4301108.