Award: OCE-2210201

Coral reefs are one of Earths most biodiverse ecosystems, and their ability to sustain a tremendous number of large fishes has long been considered an ecological enigma. This project sought to quantify links between the three-dimensional architecture of coral reefs, their fish communities, and the dominant sources and pathways of energy and nutrients in their associated food web. As part of the project, a conceptual framework to model these dynamics was introduced, which can be applied to coral reef communities worldwide as well as other marine ecosystems where fishes are the dominant group of consumers. Furthermore, data on the structural complexity of seafloor patches and their resident small, bottom-dwelling fish communities was collected on Long Reef in Belize, along with information on each patchs depth, wave exposure, and habitat type. These data show a clear relationship between the reefs three-dimensional architecture and the number and identity of fish species that live there. Ongoing collaborative work is still underway to analyze how various sources (e.g., algae, detritus, coral) and pathways (e.g., small plankton-feeding fishes, invertebrates, herbivores) of energy help to sustain larger reef fish species. In addition, using the relationship between each patchs physical characteristics and the small fish communities, current efforts are being made to scale up our estimates of energy fluxes to the area of the entire reef using three-dimensional reconstructions and drone-based aerial surveys that were conducted on the same reef. This will permit an estimate of reef-wide energy fluxes based on the recovered relationships -- an approach that can be implemented across different reefs and regions to help understand why, where, and when coral reefs can sustain high fish biomass. The outcomes of this work will be reflected in the lead PIs final report (following a no-cost extension). Two Belizean undergraduate students were given opportunities to partake in this collaborative research project, exposing them to a wide range of field- and lab-based techniques. Furthermore, the project supported two graduate students at the University of Texas at Austin and provided valuable field experiences for four other graduate students and one postdoctoral researcher. Finally, the data and findings from the project to-date (including the 3D-reconstructions) have already been used for K-12 education during the University of Texas at Austin Marine Science Institutes Summer Science Camp. Overall, the project has paved the way for a deeper understanding of the complexity and productivity of coral reefs, while providing opportunities for young aspiring scientists to immerse themselves in one of Earths most fascinating and threatened ecosystems. Last Modified: 06/28/2024 Submitted by: DouglasBRasher