Rebecca L. Hays, Ph.D.

Rebecca HaysAssistant Professor of Biology
Office: McInnis 307
Phone: 610-341-1547
Read Dr. Hays' CV


B.S. Millersville University
M.S. University of Delaware
Ph.D. University of Delaware
At Eastern Since 2011


Dr. Hays has been teaching in the Department of Biology at Eastern since 2011.  She is a native of Delaware County and coming to teach at Eastern felt like coming home.  She has always been interested in science, whether it was catching tadpoles in the summer, marveling at the leaves as they changed in the fall, or guessing which flowers might bloom first in the spring.  Her love of science led her to study Biology and Oceanography, where she focused on nutrient cycling, specifically nitrogen and phosphorus, in wetland and beach settings and tracking how ecosystems change over time.  These studies allowed her to ask the questions “why” and “how” of these ecosystems, questions any student of science is familiar with asking.  Her graduate work at the University of Delaware led to journal publications and presentations at regional, national, and international meetings.  As a graduate student, she was partially supported by a NASA Delaware Space Grant Fellowship.  She completed her postdoctoral work on a joint project with the University of Delaware and the Stroud Water Research Center focusing on nutrient utilization in ancient diatoms in the Southern Ocean.    

At Eastern, Dr. Hays helped to create the B.S. in Environmental Science major.  She serves as the faculty advisor for Earthkeepers and is on the Institutional Review Board.  She enjoys teaching her courses and labs and also taking students on field trips, where they all get to marvel at the world around them.  She also conducts research with students, focusing on examining ecosystem change using Geographic Information Systems (GIS) and aerial photography.

In her spare time, Dr. Hays loves to read anything from fiction to theology, cook and bake, and spend time with family and friends.   

Courses Taught

BIOL 105 (Introductory Biology), BIOL 152 (General Biology II), BIOL 206 (Ornithology), GEOL 200 (Geology), Marine Biology, BIOL 350B (Vertebrate Zoology), BIOL 320 (Environmental Issues), BIOL 420 (Environmental Regulations and Policy), BIOL 425, 426 (Senior Thesis Literature Review, Senior Thesis Directed Research), INST 150 (Introduction to Faith, Reason, and Justice)

Why I Teach at Eastern

I was first attracted to Eastern because it was a school that would allow me to bring both my love for science and my love for God into my classroom and my interactions with students.  When I arrived, I found a community of faculty, staff, and students that were dedicated to not only learning in the classroom, but also living out their faith in the real world.  Our students are really the main reason why I love teaching at Eastern.  They ask such important questions about science, life, and faith and engage with us in dialogue, both in and out of the classroom.  It is a blessing to teach at a university that encourages students to grow in their knowledge of academics and science and in their faith.

Research Interests

Keyword list- Ecosystem change analysis, Phragmites australis, salt marsh ecology, nutrient cycling, Geographic Information Systems (GIS), estuarine and coastal ocean ecology and processes, groundwater seepage, landscape ecology, watershed hydrology.

My research background is in nutrient cycling in beach and salt marsh ecosystems and in vegetation pattern analysis in salt marshes in the state of Delaware.  For my M.S., I examined how nutrient loads, specifically nitrogen, phosphorus, and silica, change as both fresh groundwater and recycled seawater flow through the beachface at Cape Henlopen, DE.  As part of my Ph.D. work, I expanded upon this work to determine nutrient exchanges between a salt marsh, the Murderkill Estuary (South Bowers, DE), and Delaware Bay.  At this salt marsh, I also examined the relationship between vegetation patterns and elevation in salt marshes and became interested in how invasive species, such as Phragmites australis, can establish themselves in estuarine or salt water setting. 

At Eastern, my work has focused mainly on ecosystem evolution, how an ecosystem has come to be and why it looks the way that it does.  I approach ecology from the standpoint that the biology is closely intertwined with the geology, hydrology, chemistry, and the outside forces (weather, fire, humans, etc.) that influence it.  You cannot look at an ecosystem and separate the biological changes from the abiotic circumstances and conditions that gave rise to them. 

One way to examine this sort of ecosystem evolution is by using aerial photography or satellite imagery.  Such imagery gives us a bird’s eye view of an ecosystem.  This aerial perspective allows for better mapping of the ecosystem – it allows you to see boundaries, ecotones, buildings, etc.  This enhanced viewpoint also removes the research from the ecosystem, allowing them to remove their own biases from the ecosystem classification.  For most purposes, we keep our classifications rather simplistic – buildings, roads, parking lots, forests, wetlands, grasslands, etc. – except when we are focusing on specific species.  We will start with the most recent imagery, which we can groundtruth most accurately, and move backwards in time.  Groundtruthing involves taking the images out into the field to ensure that what is seen on the image is in fact there in real life. 

By mapping an area over multiple years, you can examine how the ecosystem has evolved.  Current ecosystem evolution is most likely related to human actions and less so related to natural actions.  The way that an ecosystem has evolved will allow us to see how it has been used and impacted by humans.  Human impacts on ecosystems are not generally examined from an aerial perspective, but should be.  The aerial perspective, once again, gives us a better idea of how the system is acting and allows for changes “downstream” to be more evident.  Additionally, sometimes changes in an ecosystem are only noticeable when this time-lapse aerial approach is utilized.

One of my research groups examined historical aerial photography of Eastern’s campus and we tracked how the ecosystem changed as Eastern went from the Walton Estate to the modern-day Eastern campus.  We found that Eastern actually created more natural areas as they built the campus than there had been as part of the Walton Estate.  Another group examined how development had changed their hometowns and the rate at which natural areas were being converted to homes.  They also correlated their data to local laws regarding development or local socioeconomic factors.  I have also worked with students on expanding upon my analysis of the extent of invasive Phragmites australis in The Great Marsh, Lewes, DE.  I am hoping to identify if there are natural phenomena, such as sea level rise or weather patterns, that may be involved in the contraction and/or reduction of Phragmites australis stands.  I love working with students in my research and would ask that any interested students please contact me.   

Select Articles

  • Billups, K., Aufdenkampe, A., and Hays, R. 2013. Late Miocene through early Pleistocence nutrient utilization and export production in the Antarctic Zone of the Southern Ocean. Global and Planetary Change 100: 353-361.
  • Hays, R.L. 2009. Study Revealing Contaminants Caught in ‘Webb’ of Salt Marsh.  Estuary News 20: 14-15.
  • Hays, R.L. and W.J. Ullman. 2007. Dissolved nutrient fluxes through a sandy estuarine beachface (Cape Henlopen, Delaware, USA): Contributions from upland groundwater discharge, seawater, and diagenesis. Estuaries and Coasts 30: 710-724. (erratum Estuaries and Coasts 31: 606)
  • Hays, R.L. and W.J. Ullman. 2007. Direct determination of total and fresh groundwater discharge and nutrient loads from a sandy beachface at low tide (Cape Henlopen, Delaware). Limnology and Oceanography 52: 240-247.

Selected Abstracts of Presentations:

  • Kulfan, T.*, Goodwin, S.*, and Hays, R. 2014. Tracking Human Alteration of Rural Communities in Foster, RI and Ephrata, PA. Abstract for Saint Joseph’s University Sigma Xi Student Research Symposium 2014, Philadelphia, PA, April 2014.
  • Martin, A.*, Sioma, D.*, Underwood, S.*, and Hays, R. 2013. Mapping the changing human and natural landscapes of Eastern University from 1937-2010. Abstract for Saint Joseph's University Sigma Xi Student Research Symposium 2013, Philadelphia, PA, April 2013.
  • Hays, R.L., Aufdenkampe, A.K., and K. Billups. 2011. A Streamlined Method for Determination of 815N of Diatom-bound Organic Matter: Application to the Pliocene Southern Ocean. Abstract for the Geological Society of America Northeastern/North-Central Joint Meeting 2011, Pittsburgh, PA, March 2011.
  • Aufdenkampe, A.K., W.J. Ullman, and R.L. Hays. 2009. The role of a salt marsh in processing estuarine carbon and nitrogen: A complete species and isotope seasonal balance. Abstract for The Delaware Estuary Science and Environmental Summit 2009, Cape May, NJ, January 2009.
  • Hays, R.L. 2007.  A decade of distributional changes of Phragmites australis in the Great Marsh, Lewes, DE (1992-2002). Abstract for Estuarine Research Federation Meeting, Providence, RI, November 2007.
  • Hays, R.L. and W.J. Ullman. 2006. Groundwater Discharge and Attenuation of Nitrogen and Phosphorus Loads by Sandy Beach Sediments at Cape Henlopen, Delaware (USA). Abstract for ASLO/AGU/TOS 2006 Ocean Sciences Meeting, Honolulu, Hawaii. February 2006.
  • Hays, R.L. and W.J. Ullman. 2005. Attenuation of nitrogen fluxes during groundwater seepage across a beachface at Cape Henlopen, Delaware. Abstract for Delaware Estuary Science Conference, Cape May, NJ, January 2005.

A * indicates that the work presented was completed with Eastern University students.

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