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Updated: May 14, 2026
07:08
Long-term Behavioral and Reproductive Consequences of Embryonic Exposure to Low-dose Toxicants
Published on: March 6, 2018
Mercury exposure is associated with negative effects on turtle reproduction
Brittney C Hopkins1, John D Willson, William A Hopkins
1Department of Fish and Wildlife Conservation, 100 Cheatham Hall, Virginia Polytechnic Institute and State University , Blacksburg, Virginia 24061, United States.
Environmental Science & Technology
|January 31, 2013
Summary
Maternal mercury transfer negatively impacts turtle egg hatching success due to infertility and embryonic death. Common snapping turtles may be resilient to mercury, suitable for long-term contamination monitoring.
Area of Science:
- Environmental toxicology
- Herpetology
- Reproductive biology
Background:
- Mercury (Hg) is a toxic contaminant affecting reproduction in fish, amphibians, and birds.
- Reptilian reproductive effects of mercury exposure are understudied.
- Aquatic omnivores like the common snapping turtle are potential bioaccumulators of environmental toxins.
Purpose of the Study:
- To investigate the consequences of maternally transferred mercury on the reproductive success of the common snapping turtle (Chelydra serpentina).
- To assess the correlation between mercury levels in female turtles, their eggs, and offspring viability.
- To determine if common snapping turtles serve as effective indicators of mercury bioavailability and adverse effects.
Main Methods:
- Collected eggs and tissues from gravid female common snapping turtles along a mercury contamination gradient.
- Incubated eggs in a laboratory setting to quantify embryonic mortality, infertility, and hatching success.
- Assessed hatchlings and dead embryos for gross morphological malformations.
- Quantified mercury concentrations in female tissues and eggs.
Main Results:
- Egg mercury concentrations were positively correlated with mercury levels in female tissues.
- Increased egg mercury levels were negatively correlated with hatching success.
- Both increased egg infertility and embryonic mortality contributed to reduced hatching success.
- Common snapping turtle embryos exhibited a degree of resilience to mercury exposure compared to other amniotes.
Conclusions:
- Maternally transferred mercury significantly reduces hatching success in common snapping turtles through increased infertility and embryonic mortality.
- Common snapping turtles may be more resilient to mercury's adverse reproductive effects than previously studied amniotes.
- This species may be better suited for long-term monitoring of mercury bioavailability rather than as direct indicators of adverse effects.
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