Tag N. Engstrom

Tag N. Engstrom

Associate Professor

Department of Biological Sciences
California State University
Chico, California 95929-0515

Office: Holt 221

Campus phone # (530) 898-6748

Campus FAX # (530) 898-5060



  • Biology University Experience (BIOL 109)
  • Principles of Ecological, Evolutionary, and Organismal Biology (BIOL 152)
  • Evolution - Capstone (BIOL 302Z)
  • Field Ecology (BIOL 484)
  • Research in Biological Sciences (BIOL 600)
  • Biological Seminar (BIOL 605)
  • Methods in Population Ecology (BIOL 613)
  • Topics in Ecology/Systematics (BIOL 614)


  • Zoology, Ecology


My general research interests are in the systematics, ecology and conservation of amphibians and reptiles, particularly turtles. I currently have active research projects or supervise masters students with active research in:

  • Conservation ecology of Western Pond Turtles
  • Conservation genetics of Giant Garter Snakes
  • Conservation genetics of marine turtles
  • Conservation and invasive species issues in Hawaii
  • Systematics of softshell turtles
  • Eco-morphology of garter snakes
  • Sexual selection and asymmetry in fence lizards

Past Masters Students:

  • Eric Hansen – Eric is a biological consultant working on distribution and conservation ecology of Giant Garter Snakes in the Sacramento Valley.
  • David Kelly – Dave studied demographics, reproductive biology, population genetics and morphology of western pond turtles in the Central Valley and Foothills and is now works for the USFWS in Sacramento.
  • Akiko Masuda – Akiko is using genetic markers to trace origins of loggerhead marine turtles when she is not playing mommy to her 95 percentile in height and weight daughter.
  • Julie Nelson – Julie studied the interactions of garter snakes, Yosemite toads and pacific chorus frogs in grazed and ungrazed meadows in the Sierra Nevada. She is now working on a sea turtle nesting beach in Costa Rica.
  • Eric Olson – Eric did a herp inventory of the new Sutter Buttes State Park and is now working as a biological consultant for Condor Country Consultants.
  • Jackson Shedd – Jackson is studying sexual selection and asymmetry in western fence lizards and is also the author/illustrator of a field guide to the Amphibians and Reptiles of Bidwell Park.
  • Heyo Tjarks – Heyo is working on ecomorphology and sexual dimorphism in garter snakes using geometric morphometrics. He also sometimes jumps out of airplanes.

Past Undergrad Students:

  • Rachel Bender – Rachel worked with Dave on the WPT project and on her own project looking at co-evolution of garter snakes and the toxic newts that some species prey upon.
  • Kyle Kappenman – Kyle was a key element of Team Pond Turtle and is interested in all things herpetological