Climatic warming, sex ratios, and red-eared sliders (Trachemys scripta elegans) in Illinois

John K. Tucker, Chad R. Dolan, James T. Lamer, Emily A. Dustman

Research output: Contribution to journalArticle


Sex ratios for hatchlings and adult turtles collected in aquatic habitats were examined for red-eared sliders (Trachemys scripta elegans) collected at Long Lake in west-central Illinois. We found that sex ratios were initially balanced but became progressively more male biased with the passage of time. Large cohorts of newly recruited males seem to underlie the increasing male bias. Recruitment more than doubled between 2001 and 2004, and these turtles were strongly male biased. Climatic warming may have led to the current male bias. A period of warming at the site has allowed females to lay more eggs by lengthening the nesting season. Females are laying an extra clutch, which accounts for the increased recruitment. This clutch is laid when soil temperatures are relatively low, explaining the male bias in newly recruited turtles. The impact of the increased number of male turtles on the population is uncertain. However, female condition declined about 7% between 1994 and 2006, suggesting that an effect may be occurring.

Original languageEnglish (US)
Pages (from-to)60-69
Number of pages10
JournalChelonian Conservation and Biology
Issue number1
StatePublished - Aug 1 2008


  • Climatic warming
  • Emydidae
  • Illinois
  • Reptilia
  • Sex ratio
  • Temperature-dependent sex determination
  • Testudines
  • Trachemys scripta elegans
  • Turtle
  • USA

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Animal Science and Zoology

Fingerprint Dive into the research topics of 'Climatic warming, sex ratios, and red-eared sliders (Trachemys scripta elegans) in Illinois'. Together they form a unique fingerprint.

  • Cite this