Theo Light

Professor

Office Location: FSC 233

Phone Number: (717) 477-1093

Education

Ph.D. (2002) Ecology, University of California, Davis

B.A. (1992) Conservation and Resource Studies, University of California, Berkeley

Brief Profile

My academic training and research interests are mainly in the broad area of freshwater ecology, and focus on applied issues related to water quality, exotic species invasions, and conservation. As an undergraduate at the University of California, Berkeley, I spent two summers surveying for endangered (and exotic) crayfish in northeastern California, which led to my ongoing interest in crayfish ecology and conservation. As a graduate student and postdoc (still in California), I investigated the behavioral and food web effects of invading crayfish on native stream fish, and contributed to two projects examining broad-scale patterns of species invasions in California’s watersheds and estuaries. Since coming to Shippensburg University in 2004, I’ve incorporated more water quality questions into my research, working with students on projects ranging from the food web ecology of acidified streams to the estrogenic effects of municipal wastewater on fish. Several recent projects have used stable isotope analysis to analyze food webs and identify anthropogenic inputs to aquatic systems. I am interested in pursuing collaborative research projects with undergraduate and graduate students in these and many other areas of aquatic ecology or fisheries biology.

Research Interests

Aquatic ecology, especially of streams and rivers

Conservation biology of fish and aquatic invertebrates

Invasion ecology

Fish and invertebrates as biotic indicators of water quality

Courses Taught

BIO 162 Principles of Biology: Organismal Diversity

BIO 145 Environmental Biology

BIO 142 Introduction to Ecology

BIO 412 Ichthyology

BIO 442 Aquatic Ecology

BIO 464 Freshwater Invertebrate Zoology

BIO 593 Biometry (graduate)

BIO 594/595 Special Topics: Community Ecology (graduate)

Undergraduate Student Research Projects

Alicia Helfrick (2009 – 2011), Elizabeth Murphy (2010 – 11), and Hannah Richardson (2011-12): Diet and behavior of Appalachian brook crayfish in acidic and neutral pH mountain streams

Mark Shaeffer (2009 – 2010) Diversity and composition of Pennsylvania fish communities: assessing changes over time

Karen Burke, Rachael Kells, and Emilie Kohler (2007 – 2008) An investigation into hybridization between two related species of crayfish in Central Pennsylvania

Kaitlyn Travis (2008) Comparison of the ecological impacts of Orconectes virilis and Orconectes rusticus on community structure in freshwater streams of south-central Pennsylvania

MS Student Research Projects

Tammy Smith (2012 – ) Invertebrate and chemical assessment of water quality in Middle Spring Creek, Shippensburg, PA

Lauren Kesslak (2011 – 2012) Intersex in blacknose dace (Rhinichthys atratulus) downstream of waste water treatment plants in south-central Pennsylvania

Sara Grisé (2009 – 2011) Climate change and aquatic invasive species risk in Pennsylvania

Bill Humbert, Cynthia Tucker, Amanda Ritz and Lauren Kesslak (2010 – 2011) Land-use effects on fish health and biotic integrity in streams of the Susquehanna River drainage

Steve Chervenyak (2009 – 2010) Effects of stream acidification and predation risk on the dietary niche width of Appalachian brook crayfish Cambarus bartonii

Eric Snyder (2007 – 2009) Do invasive rusty crayfish (Orconectes rusticus) increase predation on tessellated darter (Etheostoma olmstedi) by largemouth bass (Micropterus salmoides)?

Selected Publications

Baer-Lehman, M.L., T. Light, N.W. Fuller, K.D. Barry-Landis, C.M. Kindlin, and R.L. Stewart, Jr. 2012. Evidence for competition between Ixodes scapularis and Dermacentor albipictus feeding concurrently on white-tailed deer. Experimental and Applied Acarology 58: 301–314.

Lapointe, N. W. R. and Light, T. 2012. Landscape-scale determinants of non-native fish communities. Diversity and Distributions 18: 282–293.

Light, T. 2009. Using case studies to reinforce the scientific method and core concepts in a non-majors class. Journal of the Pennsylvania Academy of Science 82:107-110.

Light, T. and M.P. Marchetti. 2007. Distinguishing between invasions and habitat changes as drivers of diversity loss among California’s freshwater fishes. Conservation Biology 21(2): 434–446.

Marchetti, M.P., J.L. Lockwood, and T. Light. 2006. Effects of urbanization on California’s fish diversity: differentiation, homogenization, and the influence of spatial scale. Biological Conservation 127(3):310-318.

Light, T. 2005. Behavioral effects of invaders: alien crayfish and native sculpin in a California stream. Biological Invasions 7(3):353-367.

Marchetti, M.P., T. Light, P.B. Moyle and J. Viers. 2004. Fish invasions in California watersheds: testing hypotheses using landscape patterns. Ecological Applications 14(5):1507–1525.

Light, T. 2003. Success and failure in a lotic crayfish invasion: the roles of hydrologic variability and habitat alteration. Freshwater Biology 48(10):1886-1897.