Leo Nico, Ph.D.



Ph.D., Zoology, University of Florida, 1991
Dissertation: Trophic Ecology of Piranhas (Characidae: Serrasalminae) from Savanna and Forest Regions in the Orinoco River Basin of Venezuela. (Committee Co-Chairs: Horst Schwassmann and Carter Gilbert)

M.S., Biology, Southern Illinois University, 1982
Thesis: Life History and Ecology of Orinoco Basin Annual Killifish. (Committee Chair: Jamie E. Thomerson)

B.A., Biology with Departmental Honors, Southern Illinois University, 1979


Leo Nico is a Research Fishery Biologist with the US Department of Interior and US Geological Survey (1993-present).  The mission of his USGS research program is to conduct basic and applied research on invasive and other nonindigenous fishes.  Over the course of his non-government and government career, Nico has conducted research throughout the USA and in other parts of the world, including Venezuela, Brazil, Ecuador (including the Galapagos), Southeast Asia (Thailand), and Micronesia (e.g., Guam, Palau).  He has authored over 50 scientific and popular publications including two books on nonindigenous fishes and is one of the DOI’s authorities on nonindigenous fishes.  

Nico is basically an ichthyologist by training and his research is diverse.  Together with an assortment of US and foreign collaborators, he has conducted research and published widely on a variety of both invasive and native fishes, covering such topics as natural history, ecology, aquatic biology, taxonomy/systematics, biogeography, genetics, age and growth, risk assessments and ecological impacts of invasive fishes, geographic distribution and dispersal of invasive fishes, eradication of invasive fishes, among other fields.  A few of the nonindigenous fishes that he has studied include Asian swamp eel (Synbranchidae), black carp (Cyprinidae), suckermouth armored catfishes (Loricariidae), and various cichlids (e.g., tilapia).  

Nico is involved in various new projects--including collaborative research on parasites and introduction pathways of Asian swamp eel and an analysis and assessment of methods to eradicate invasive fish populations.


Leo Nico was born in Illinois and grew up in a small town in the southern part of the state.  He received his BSc (1979) and MSc (1982) degrees in Biological Sciences from Southern Illinois University – Edwardsville.  Upon completion of his MSc, Nico spent the next two years in Venezuela where he was affiliated with the University of the Llanos (UNELLEZ) and collaborated with professor Don Taphorn conducting research and field work on freshwater fishes.  Following that hiatus, he was acceptted into the University of Florida – Department of Zoology – where he received his PhD in 1991.  For his MSc and PhD research Nico conducted field work in South America and intermittently continued to travel and conduct research on freshwater fishes in the Neotropics – ultimately -- between 1980 and 2010 spending some 5+ years in that region of the world.