October 11, 2022

How do coral energy strategies influence their survival?

Scuba diving

Most tropical reef-building corals are mixotrophic, acquiring autotrophic nutrition from their photosynthetic algal endosymbionts and heterotrophic nutrition via predation of plankton. This flexible trophic strategy is thought to underpin their ability to colonise a range of depths, habitats and oceanographic contexts that vary in energetic resource availability. Laboratory experiments suggest coral heterotrophy might explain the ability of some corals to persist in challenging environments, including highly turbid reefs where light levels can be very low. This is because heterotrophy provides a valuable nutritional source that can support coral growth despite reduced autotrophic contributions from the algal endosymbionts. Coastal darkening, a consequence of increasingly turbid nearshore waters, is impacting coral reefs worldwide. Nevertheless, we know very little about how coral trophic strategies vary in response to spatial and temporal gradients in resource availability and whether and how trophic plasticity might enable some corals to persist under these increasingly challenging coastal conditions. This PhD project will therefore answer a fundamental question within coral reef science: Do coral feeding strategies track gradients in energetic resource availability and does this trophic plasticity facilitate coral survival?

Specifically, the project will: 1) determine how coral trophic strategies vary spatially within and between reef habitats that differ in energetic resource availability, 2) test whether coral trophic strategies vary in response to temporal fluctuations in energetic resource availability, and 3) determine if trophic plasticity provides physiological benefits that might facilitate coral survival under high levels of coastal darkening. With fieldwork at several of the world’s most remote (Palmyra Atoll) and seasonally dynamic (Red Sea) coral reefs in collaboration with KAUST, The Nature Conservancy and the U.S. Fish & Wildlife Service, an internship at NOAA and supervisory support at Bangor University and Lancaster University, the project offers unparalleled opportunities for research training and exposure to world-leading applied ecosystem science.

Applicants should hold a minimum of a UK Honours Degree at 2:1 level or equivalent in subjects such as Marine Biology, Biology, Marine Ecology, Ecology, Environmental Science, or Coastal Marine Science. Applicants with Masters degrees, or those with relevant research experience (e.g. stable isotope ecology) and field training (e.g. data management, statistics, GIS, scientific SCUBA diving) will be highly competitive.

For further details, or to enquire about eligibility please send a short statement regarding your background and interest in the project, and a CV to Dr. Gareth Williams