We study how microorganisms influence their animal and plant hosts, as well as ecosystem processes, under environmental stress.

Current Projects

A multi-scale approach to predicting coral disease spread: leveraging an outbreak on coral-dense isolated reefs. OCE-2316578, Co-PIs: Marilyn Brandt, Amy Apprill, Dan Holstein

Over the last four decades, diseases decimated ecosystem engineers in marine coastal environments, including coral reefs. Recent results from studies of white plague and stony coral tissue loss disease (SCTLD) show coral species immune traits can influence disease resistance and therefore predict of coral community structure post-outbreak in the Caribbean. In late August of 2022, an unidentified multi-species acute tissue loss disease with signs and species susceptibility characteristics reminiscent of white plague or SCTLD was documented at the Flower Garden Banks (northwest Gulf of Mexico, GoM). This disease is having significant impacts on FGB and could become widespread across the GoM, offering an opportunity to test hypotheses about the influence of coral community composition and pathogen dispersal on disease spread during the early stages of an outbreak; few studies examine this on relatively isolated, deep, coral-dense reefs. The interdisciplinary research team employs photomosaics and colony fate-tracking, layered molecular datasets and microscopy approaches, as well as modeling of disease reservoirs and dispersal to assess the etiology of the disease and contribute to the development of a generalizable framework for disease spread on reefs. By parsing the impacts of reef-scale community composition versus seascape-scale dispersal in disease transmission and persistence, this work helps reveal the potential resistance and resilience of isolated, coral-dense reefs to diseases that decimate these ecosystems across the wider Caribbean.

Testing the effects of predator-derived feces on host symbiont acquisition and health. OCE-2145472

Climate change and local-scale anthropogenic stressors are degrading coral reefs across the globe. When conditions become too stressful on reefs, corals can lose beneficial microbial symbionts (e.g., dinoflagellates in the family Symbiodiniaceae) that live in their tissues via a process called “bleaching”. Although Symbiodiniaceae play key roles in the health of coral colonies, we know little about the processes that make symbionts available in the environment to prospective host corals. This research tests the extent to which coral-eating fish feces, which contain live Symbiodiniaceae, facilitate symbiont acquisition by corals in their early life stages. It will generate seminal knowledge on how corallivore feces impact coral symbioses and health, and will assess the ecological importance of corallivorous fishes as drivers of coral symbiont assemblages. This research also tests the extent to which corallivore feces are a source of food and nutrients that impact coral health; this has particular relevance to the survival and recovery of bleached adult corals. This research can ultimately inform intervention strategies to support reef resilience and mitigate reef degradation.

A multi-scale approach to predicting infectious multi-host disease spread in marine benthic communities. OCE-2109622Co-PIs: Marilyn Brandt, Amy Apprill, Dan Holstein, Laura Mydlarz

Over the last four decades, marine diseases have decimated ecosystem engineers in marine coastal ecosystems, including the rocky intertidal, seagrasses and coral reefs. The pathogens driving these diseases have frequently been challenging to isolate, characterize and confirm, in part because they affect multiple host species and can spread by ocean currents, as well as through individual contact. We propose a multi-scale epidemic model for studying marine disease that addresses both within-host and within-patch disease dynamics, and explicitly acknowledges the dispersal of pathogens between populations. Our interdisciplinary research team of ecologists, connectivity and disease modelers, microbiologists, and coral immunologists will integrate the largest set of predictors of marine disease spread to date: individual host species traits that allow for disease resistance or susceptibility, local transmission within communities that may have unique community structure, and hydrodynamic connectivity among susceptible communities. Modeling will be supported with rich data sets of within- and among-patch population characteristics and disease dynamics as well as molecular data on species-level disease responses. This project will advance knowledge of infectious diseases by integrating multidimensional scales and differential host susceptibilities into existing epidemiological models. This model will particularly advance the framework for studying marine diseases and has the potential to elucidate the transmission properties of a devastating Caribbean coral disease (stony coral tissue loss disease) that fits the most confounding and notorious hallmarks of marine diseases: infection of multiple hosts by an elusive pathogen.

blue white UC berkeley logo

Department of Environmental Science, Policy and Management

Logo and Art Credit: Janavi Mahimtura Folmsbee, @janavimfolmsbee 

© Adrienne Simoes Correa 2016