Zachery R. Staley

Quantification of fecal indicator bacteria at the surface-water interface at four Great Lakes beaches

Fecal contamination results in over 10% of beach advisories, resulting economic loss and increased risk to human health. Non-point sources, such as groundwater and beach sand, can act as a reservoir for E.coli, harboring concentrations orders of magnitude higher than those found in adjacent waters. However, the microbial contribution of these sources to fecal indicator bacteria concentrations in adjacent waters is not well characterized. The goal of this project is to quantify, via culturable methods and quantitative polymerase chain reaction (qPCR), the concentrations of E. coli and enterococci in beach sand/sediment, ground water, and adjacent lake water. These results should help in understanding the contribution from non-point reservoirs to bacterial concentrations in recreational waters. Additionally, host-specific molecular markers will be quantified to attempt to determine the source(s) of fecal contamination.

Personal Background

Zach joined the RESTORE group in June 2013. He completed his Ph.D. in Biology, with a concentration in Environmental and Ecological Microbiology, in May 2013 from the University of South Florida. His Ph.D. research focused on the effects of agrochemicals on the growth and survival of fecal indicator bacteria (E. coli and enterococci), bacterial pathogens (E. coli O157:H7 and Salmonella enterica) and viruses (human polyomavirus and human adenovirus). This research examined both direct effects of the agrochemicals themselves on bacterial survival as well as investigating indirect effects of agrochemicals on bacterial survival mediated via factors such as protozoan predation, competition and algal populations.

Conferences


  • 2009. Z. Staley, J. Rohr, and V. J. Harwood Direct toxicity effects of agrochemicals on indicator bacteria. ResearchOne Graduate Student Research Symposium, Tampa, FL Oct 8.
  • 2009. Z. Staley, J. Rohr, and V. J. Harwood. Direct effects of agrochemicals on indicator bacteria. Southeastern Branch ASM Annual Meeting, Savannah, GA Nov 6-7.
  • 2009. Zachery R. Staley, Chris Staley, Cheryl Wapnick, Valerie J. Harwood. A weight of evidence approach allows more accurate assessment of sources of fecal indicator bacteria in surface waters. Water Environment Federation TMDL Conference, Minneapolis, MN Aug 9-12.
  • 2010. Z. Staley, J. Rohr, and V. J. Harwood. The effects of agrochemicals on the fate of fecal indicator bacteria in surface waters. Land Grant & Sea Grant National Conference, Hilton Head, SC, Feb 21-25.
  • 2010. M. Penugonda, Z. Nisbeth, C. Mitraki, Z. Staley, P. Wanjugi, M. Brownell, B. Badgley, and V. J. Harwood. Using replicate phosphate lakes to investigate the effects of land use on the contamination of water by fecal indicator bacteria. National Conferences for Undergraduate Research, University of Montana, MT, April 15-17.
  • 2010. Z. Staley, J. Rohr, and V. J. Harwood. Investigation of Direct and Indirect Effects of Agrochemicals on Fecal Indicator Bacteria. American Society for Microbiology, 110th General Meeting, San Diego, CA, May 23-27.
  • 2011. Z. Staley, J. Senkbeil, J. Rohr, and V. J. Harwood. Predicting the effects of agricultural practices on waterborne human pathogens, livestock helminthes, and the health of rural water-bodies. Water and Watershed & Agricultural Water Science Programs Project Directors Meeting, Washington D. C., Feb 2.
  • 2011. J. Senkbeil, Z. R. Staley, J. R. Rohr, and V. J. Harwood. Effects of agrochemicals on the growth rates of bacterial pathogens and fecal indicator bacteria. AACR 102nd Annual Meeting 2011, Orlando, FL, Apr 2.
  • 2011. Z. R. Staley, J. R. Rohr, and V. J. Harwood. Direct effects of agrochemicals on pathogens and fecal indicator bacteria. American Society for Microbiology, 111th General Meeting, New Orleans, LA, May 21-24.
  • 2011. Z. R. Staley, E. Chase, C. Mitraki, J. Senkbeil, T. L. Crisman and V. J. Harwood. The effects of land use on fecal microbial levels in artificial phosphate mine lakes. American Society for Microbiology, 111th General Meeting, New Orleans, LA, May 21-24.
  • 2011. Z. R. Staley, J. R. Rohr, and V. J. Harwood. Direct effects of agrochemicals on pathogens and fecal indicator bacteria. Southeastern Branch ASM Annual Meeting, Gainesville, FL, Oct 20-22.
  • 2011. J. K. Senkbeil, Z. R. Staley, J. R. Rohr, and V. J. Harwood. Effects of agrochemicals on the growth rates of bacterial pathogens and fecal indicator bacteria. Southeastern Branch ASM Annual Meeting, Gainesville, FL, Oct 20-22.
  • 2012. Z. R. Staley, J. Rohr, and V. J. Harwood. Effects of agrochemicals on bacterivorous predation. American Society for Microbiology, 112th General Meeting, San Francisco, CA, June 16-19.

Grants


  • 2003. Office of Undergraduate Research, University of South Florida, Undergraduate Research Grant
  • 2004. Office of Undergraduate Research, University of South Florida, Undergraduate Research Grant
  • 2006. Office of Undergraduate Research, University of South Florida, Undergraduate Research Grant
  • 2010. American Society for Microbiology Student Travel Grant.

Publications

Staley, Z. R., Senkbeil, J. K., Rohr, J. R., and Harwood, V. J. 2013 The effects of agrochemicals on bacterivorous predation and competition in a freshwater environment. Ecol Appl In Review

Staley, Z. R., Chase, E., Mitraki, C., Crisman, T. L., and Harwood, V. J. 2013. Microbial water quality in freshwater lakes with different land use. J. Appl Microbiol doi: 10.1111/jam.12312. Epub ahead of print

Staley, Z. R., Senkbeil, J. K., Rohr, J. R., and Harwood, V. J. 2012. Lack of direct effects of agrochemicals on zoonotic pathogens and fecal indicator bacteria. Appl Environ Microbiol. 78 (22), 8146-8150.

Byappanahalli, M. N., Nevers, M. B., Korajkic, A., Staley, Z. R., and Harwood, V. J. 2012. Enterococci in the environment: a review. Microbiol Mol Biol Rev 76 (4), 685-706.

Staley, Z.R., Rohr, J.R. and Harwood, V.J. 2011 A test of direct and indirect effects of agrochemicals on the survival of fecal indicator bacteria. Appl Environ Microbiol 77 (24), 8765-8774.

Staley, Z. R., Rohr, J. R. and Harwood, V. J. 2010. The effect of agrochemicals on indicator bacteria densities in outdoor mesocosms. Environ Microbiol 12 (12), 3150-3158.