Columbia Environmental Research Center

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    • Tanner, Mike
    • Tegerdine, George
    • Thorsby, Roy, , Hydrologic Technician
    • Tillitt, Donald, PhD, Branch Chief, Biochemistry/Physiology
    • Tillitt, Robin
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    • Troutt, Eric, ASRC, Biologist I
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CERC Internet Home Page -> Staff -> Donald Tillitt PhD, Branch Chief, Biochemistry/Physiology
Donald Tillitt PhD, Branch Chief, Biochemistry/Physiology
Donald Tillitt PhD, Branch Chief, Biochemistry/Physiology
Appointment Type: USGS
Staff Type: Center Staff
Duty Station: Columbia Environmental Research Center
Job Title: Supervisory Research Chemist
Email: dtillitt@usgs.gov
Phone: (573) 876-1886
Fax: (573) 876-1896
URL: http://www.cerc.usgs.gov/Staff.aspx?StaffId=202
I lead an active research program on the effects of chemicals on fish and wildlife, with an emphasis on reproduction and development in fish. Our research interests focus on developmental effects of persistent chemicals in fish. Multiple levels of biological organization are generally evaluated in our research efforts, with endpoints consisting of molecular, biochemical, histology, and behavioral-level effects. Current research projects in our laboratory include 1) effects of contaminants on visual development and linkages to behavioral deficits (predator avoidance and prey capture); 2) causes and effects of thiamine deficiencies on Great Lakes salmonines; and 3) effects of chemicals on sexual differentiation and gonad development in fish; 4) effects of atrazine on fish reproduction and development; 5) gene expression patterns along the hypothalamus-pituitary-gonad axis of fish after methylmercury exposure; and 6) characterization of steroid hormones, gonadotrophins, and gonad development patterns in shovelnose sturgeon.
Affiliations
  • International Association of Great Lakes Research
    (1/1/1988)
    Active Member
  • Society of Environmental Toxicology and Chemistry
    (1/1/1988)
    Active Member
  • American Fisheries Society
    (1/1/1985)
    Active Member
Education
  • PhD, Michigan State University, East Lansing
    (5/1/1989)
    Environmental Toxicology/Fisheries and Wildlife, Dissertation title: Assessment of Complex Mixtures of Planar Chlorinated Hydrocarbons in Great Lakes Fish and Wildlife.
  • Master's of Science, Michigan State University, East Lansing
    (5/1/1986)
    Fisheries and Wildlife (Fish Physiology), Thesis title: In Vitro Mitogenesis of Peripheral Blood Lymphocytes from Rainbow Trout (Salmo gairdneri)
  • Bachelor of Science, Michigan State University, East Lansing
    (5/1/1981)
    Ag Biochemistry and Fisheries and Wildlife
Experience
  • Biochemistry and Physiology Branch Chief
    (8/1/1997)
    from 1997 to present, Columbia Environmental Research Center
  • Organic and Biochemistry Section Leader
    (7/1/1990)
    1990 to 1997, Columbia Environmental Research Center
University Appointments
  • Adjunct Faculty, Department of Fisheries and Wildlife, University of Missouri, Columbia
    (1/1/2001)
    2001 to present, Instuctor: Environmental Toxicology
  • Adjunct Faculty, Biochemistry Department, University of Missouri - Columbia
    (1/1/1991)
    1991 to present
Branches
Current Research Projects
In The News
  • Wednesday, September 16, 2009
    Study: Gender-Bending Fish Widespread in U.S.
    (National Public Radio (NPR))
    A survey of fish in rivers and streams around the country shows that a large percentage of male bass have acquired feminine characteristics. Scientists say it's the biggest survey of this gender-bending condition in U.S. waters. And while they can't be sure of the cause, they suspect industrial and pharmaceutical chemicals are the culprit.
  • Tuesday, September 15, 2009
    13 of the Most Gender-Bent U.S. Rivers
    (The Daily Green)
    The nation's fish -- particularly two species popular with anglers -- are facing a widespread and ill-defined threat that is blending their genders. In the most comprehensive study to date -- of 16 species in nine river systems over nine years -- government scientists have for the first time documented the surprising pervasiveness of so-called intersex fish.
  • Tuesday, September 15, 2009
    Widespread Occurrence Of Intersex Bass Found In U.S. Rivers
    (Science Daily)
    Of the 16 fish species researchers examined from 1995 to 2004, the condition was most common by far in smallmouth and largemouth bass: a third of all male smallmouth bass and a fifth of all male largemouth bass were intersex. This condition is primarily revealed in male fish that have immature female egg cells in their testes, but occasionally female fish will have male characteristics as well.
  • Tuesday, September 15, 2009
    More Hermaphrodite Fish in U.S. Rivers
    (Discovery Channel)
    Male fish with female body parts have been showing up in our nation's rivers for a while now, but a new study found a surprising number of mixed-up fish.
    From the Mississippi to the Rio Grande, from the Appalachia to the Colorado, researchers found large numbers of river fish with egg cells in their testes, particularly in two species: smallmouth and largemouth bass.
  • Tuesday, September 15, 2009
    U.S. Finds Hermaphroditic Bass Widespread in Nation's Rivers, Including Columbia
    (Oregon Environmental News)
    Sexual deformities in smallmouth and largemouth bass are more widespread than previously thought in river basins across the country, including the Columbia River basin in the Northwest.
  • Tuesday, September 15, 2009
    In Western Colorado, A Rising Number of Intersex Fish
    (Colorado Independent)
    A new study released Monday finds surprisingly high incidences of male fish carrying immature eggs in their testicles. The “intersex” fish are appearing throughout the nation, including in western Colorado. The study did not examine why the aquatic hermaphrodites were so prevalent in the nation’s waterways, though lead author Jo Ellen Hinck suggested it was unlikely any one human activity or contaminant was responsible. She added that far more research would have to be conducted before any reliable assertions could be made on the matter.
  • Tuesday, September 15, 2009
    Male Bass in Many US Rivers Feminized, Study Finds
    (The Washington Post)
    Government scientists figure that one out of five male black bass in American river basins have egg cells growing inside their sexual organs, a sign of how widespread fish feminizing has become. The findings come from the U.S. Geological Survey in its first comprehensive examination of intersex fish in America, a problem linked to women's birth control pills and other hormone treatments that seep into rivers. Sporadic reports of feminized fish have been reported for a few years.
  • Tuesday, September 15, 2009
    Gender-bending Bass Found in Yampa River
    (Denver Post)
    Male bass in Colorado rivers and other basins around the nation widely exhibit feminine sex traits, a federal fish study released Monday shows. This gender-bending was most common in the southeastern U.S. as well as in western Colorado, in the Yampa River, where 70 percent of male bass had eggs developing alongside their testicular organs, the U.S. Geological Survey study found.
  • Tuesday, September 15, 2009
    Widespread Occurrence of Intersex Bass Found in U.S. Rivers
    (Sign of the Times - The Living Planet)
    Intersex in smallmouth and largemouth basses is widespread in numerous river basins throughout the United States is the major finding of the most comprehensive and large-scale evaluation of the condition, according to U.S. Geological Survey (USGS) research published online in Aquatic Toxicology.
  • Monday, September 14, 2009
    Widespread Occurence of Intersex Bass Found in U.S. Rivers
    (USGS Newsroom Press Release)
    Intersex in smallmouth and largemouth basses is widespread in numerous river basins throughout the United States, is the major finding of the most comprehensive and large-scale evaluation of the condition, according to U.S. Geological Survey (USGS) research published online in Aquatic Toxicology.
    Contact: Jo Ellen Hinck at 573-876-1808 or jhinck@usgs.gov
    CERC Pub Brief
  • Monday, September 14, 2009
    Intersex Bass Found in U.S. River Basins
    (United Press International - Science News)
    A U.S. Geological Survey study has found intersex in smallmouth and largemouth bass to be widespread in numerous U.S. river basins. USGS scientists said their finding is the result of the most comprehensive and large-scale evaluation of the condition, which is primarily revealed in male fish having immature female egg cells in their testes, and occasionally female fish with male characteristics as well.
  • Monday, September 14, 2009
    American Rivers Could Be Causing Intersexed Fish
    (KTXL Sacramento)
    The agency looked at past data from nine river basins - covering about two-thirds of the country - and found that about 6 percent of the nearly 1,500 male fish had a bit of female in them. The study looked at 16 different species, with most not affected. But the fish most feminized are two of the most sought-after freshwater sportfish: the largemouth and smallmouth, which are part of the black bass family. Those two species were also the most examined with nearly 500 black bass tallied.
  • Monday, September 14, 2009
    Widespread Occurrence of Intersex Bass Found in US Rivers
    (e! Science News)
    Intersex in smallmouth and largemouth basses is widespread in numerous river basins throughout the United States is the major finding of the most comprehensive and large-scale evaluation of the condition, according to U.S. Geological Survey (USGS) research published online in Aquatic Toxicology. Of the 16 fish species researchers examined from 1995 to 2004, the condition was most common by far in smallmouth and largemouth bass: a third of all male smallmouth bass and a fifth of all male largemouth bass were intersex. This condition is primarily revealed in male fish that have immature female egg cells in their testes, but occasionally female fish will have male characteristics as well.
  • Monday, September 14, 2009
    Male Bass in Many US Rivers Feminized, Study Finds
    (San Diego Union-Tribune)
    Government scientists figure that one out of five male black bass in American river basins have egg cells growing inside their sexual organs, a sign of how widespread fish feminizing has become. The findings come from the U.S. Geological Survey in its first comprehensive examination of intersex fish in America, a problem linked to women's birth control pills and other hormone treatments that seep into rivers. Sporadic reports of feminized fish have been reported for a few years.
CERC Publications
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