FIELDWORK
HAWAII, CORAL BLEACHING AND REPRODUCTION, 2017-PRESENT
Most prior coral bleaching studies have focused on the potential of adult colonies to recover and acclimatize from stress. However, future reefs will not only require the survival of adults, but will also be dependent upon the continuation of sexual reproduction despite thermal stress. Little is known about the mechanisms corals use to tolerate and successfully reproduce in stressful environments. This interdisciplinary study will characterize the physiological and phenotypic responses associated with thermal stress and quantify the impacts of coral nutrition to reproduction. The research will focus on an important and dominant reef builder in Hawaii that has the capacity to sexually reproduce despite bleaching. The objectives are to: (1) independently track the contribution of carbon and nitrogen acquired from parental photosynthesis and heterotrophy to gamete development in bleached and unbleached colonies; (2) develop nutritional proteome profiles of bleached and unbleached parental colonies and their eggs that have relied on different trophic sources throughout gamete development; and (3) use the proteomic surveys to develop a biomarker assay for coral trophic status. The findings of this study will detect biomarkers that can serve to monitor trophic status and identify coral species that are likely to recover and reproduce after a bleaching event. Altogether these data can be applied to conservation and management efforts and the development of accurate forecasting models. This research is in collaboration with Jacqueline Padilla-Gamino from the University of Washington and is funded by the National Science Foundation.
SOUTHWEST PUERTO RICO, LAND-BASED SOURCES OF POLLUTION TO REEFS, 2014-PRESENT
Rivers transport excess nutrients, sediments, and other pollutants from land to the coast causing both acute and chronic stress to coral reef ecosystems. Although these conduits of delivery are well understood, establishing riverine pollutant thresholds that directly impact coral reef health has remained elusive. To address this problem, dry- and wet-season analyses of river pollutants and associated measurements in nearshore coral reef health in the Guánica region of Puerto Rico are being conducted. In particular, the project seeks to (1) quantify total maximum daily load values for each pollutant throughout the system to discern the threshold for acute stress on coral health; (2) identify point source impacts and mitigation success of existing riparian buffers; and (3) identify the timing of land use thresholds that triggered chronic stress in the past. These efforts are designed to support effective watershed management and healthy coral reef ecosystems. This work entails a collaboration with Dr. Steven Goldsmith in the Department of Geography and the Environment at Villanova University.