Garrett Barr, Ph.D.
Associate Professor of Biology and Environmental Science
Office: 309 Parente
Phone: 570-208-5900 x5729

Educational Background

B.S.,   Biology, Binghamton University, 1995                  

M.S., Natural Resources: Wildlife Ecology, University of New Hampshire, 2000

  • Effects of biotic and abiotic factors on larval Plethodontid salamanders

Ph.D., Natural Resources and Environmental Science, University of New Hampshire, 2007

  • The roles of brook trout and larval two-lined salamanders as predators in streams

Courses Taught

  • Biol 113 Evolution and Diversity
  • Biol 210 Organisms and Their Ecosystems
  • Biol 430 Ecology
  • Enst/Biol 410 Ecological & Environmental Sampling and Analysis
  • Enst/Biol 401A Conservation Biology
  • Enst/Biol 401K Wetland Ecology and Delineation
  • Biol/Enst 401M Tropical Ecosystems: Forests of the Peruvian Amazon (short-term study abroad course)

Research Interests   

I am a community ecologist and primarily study interactions among fish, salamanders, and macroinvertebrates in small streams. My interest in aquatic ecology sort of started with a love of mountains (White Mountain National Forest in NH), and I was quickly captured by the interesting interactions among predators and prey in streams. All organisms are consumers but are also consumed by others. For example, stream salamander larvae actively search for invertebrate prey while trying to avoid becoming prey to larger invertebrates, other salamanders, and fish. These tradeoffs between gathering resources and not becoming a resource for another organism can be fascinating at the individual, population, or community levels.

I am also investigating some aspects of environmental degradation in the region. One big and obvious source of pollution to local surface water is abandoned mine drainage. I’ve been studying the effects of the Old Forge Bore Hole on water and habitat quality in the Lackawanna River. The mine drainage has clear impacts on the Lackawanna River, but habitat and water quality are not good up-river of the bore hole. This has led me to study degradation along the length of the Lackawanna.

I’ve also been studying the effects of acidification (sort of the old acid rain issue) in local conservation lands. The occurrence and effects of acidification across the northeastern US aren’t new, but I stumbled across the issue while looking for field sites for other projects. I often look for streams with waterfalls to study because (they’re beautiful places, and) they can be great sites to study the effects of predators in streams. I found some streams with big, beautiful waterfalls that are effective barriers to fish movement. In the fishless reaches above the falls, I found very few salamanders where they should be thriving. Chronic and episodic acidification (due to a combination of atmospheric deposition, geology, and wetlands) seem to be important issues in these streams, and I’m study their impacts on fish, salamanders, and macroinvertebrates.

Recent Conference Presentations with Students

Laird, A and G Barr 2014. Tracking Digestion in Larval Two-Lined Salamanders with Fluorescently Marked Prey. Poster presented at the 90th Annual Meeting of the Pennsylvania Academy of Science.

Madden, S and G Barr 2014. Effects of Marking Larval Salamanders on Their Survival in the Presence of Trout and Crayfish. Poster presented at the 90th Annual Meeting of the Pennsylvania Academy of Science.

Minier, S and G Barr 2014. Chronic and Episodic Acidification of Fishing Creek: Effects on Two-lined Salamander Abundance. Poster presented at the 90th Annual Meeting of the Pennsylvania Academy of Science. 

Sohle, B and G Barr 2013. Use of Cover by Prey in Response to Single and Multiple Predator Species. Poster presented at the 89th Annual Meeting of the Pennsylvania Academy of Science.

Bauza, J, B Sohle, and G Barr 2012. Anti-Predator Behavior Exhibited by Stream Macroinvertebrates When Exposed to Multiple Predators. Poster presented at the 88th Annual Meeting of the Pennsylvania Academy of Science.

Stavish, G and Garrett Barr 2012. Effects of Fish on the Feeding Habits of Salamanders in Streams. Poster presented at the 88th Annual Meeting of the Pennsylvania Academy of Science.

Rafter JL* and GE Barr 2010 Impacts of stocking trout on resident fish and benthic macroinvertebrates in streams in Northeastern PA. Poster presented at the 95th Annual Meeting of the Ecological Society of America. Pittsburg, PA.


  • Barr GE and KJ Babbitt. 2007. Trout affect the density, activity, and feeding of a larval Plethodontid salamander. Freshwater Biology 52:1239-1248.
  • Barr GE and KJ Babbitt 2002. Effects of biotic and abiotic factors on the distribution and abundance of Eurycea bislineata. Oecologia. 133:176-185.
  • Barr GE and KJ Babbitt 2001. Two methods to sample larval Plethodontid salamanders in streams. Wildlife Society Bulletin. 29(4):1238-1242