With funds from this Small Grant for Exploratory Research (SGER), investigators at Stanford University will collaborate with coleagues at the University of Hawaii at Manoa to investigate an area of emerging importance in oceans and human health that has not been studied extensively in the past: the sources, fate, and transport of microbial pollutants in tropical marine waters. This emerging area was proclaimed by experts at the USEPA-sponsored Pellston-style workshop on microbial pollution in Spring 2007 as one of the most important to pursue in the next 2-5 years. The research team expects to make major strides toward establishing a framework for evaluating sources of microbial pollutants in tropical waters and will establish the use of a new source tracking tool.
The study area, Hanalei Bay, located on the North Shore of Kauai, is one of the top five tourist beaches in the U.S. The Bay's beneficial uses include fishing, swimming, surfing, and boating. Hanalei Bay has the worst microbial water quality in the state of Hawaii, according to the National Resources Defense Council; 43% of the water samples taken in the bay near the mouth of the Hanalei River (an American Heritage River) in 2005 were in violation of water quality criteria. Preliminary research in Hanalei Bay suggests that humans contribute to microbial pollution in the bay. This is not surprising inasmuch as the community relies exclusively on septic systems and cesspools for wastewater disposal. The bay represents an ideal environmental to test and showcase new tools and methods for assessing human contributions of microbial pollution to tropical waters.
The project will feature a tiered approach to microbial source tracking using novel tools developed as part of the proposed work and at PRCMB. In the first tier, the team will characterize near shore water quality in Hanalei Bay and identify potential sources near the bay using microbial indicators. This will yield insight into the physical and biological controls on the abundance and distribution of microbial pollution in the Bay and will identify regional scale predictors of unsafe conditions. In the second tier, they will use source tracking tools as well as assays for human pathogens to determine if microbial pollutants are from a human source or represent a human health risk. The centerpiece of the project will be the development of a novel esp gene source tracking assay and the testing of its validity for tracking human enterococci in tropical marine waters. In addition, Vibrio and enterococci isolates obtained during the work will be added to the investigators' culture collections for further genetic characterizations using comparative genetic techniques.
In addition to the obvious broader impacts that this research could have on the study of human health - water quality issues in tropical marine settings, it would also provide some support for graduate student participation.
