As with most other turtle species, the incubation temperature of western pond turtle eggs determines the gender of the turtles developing inside. Those incubated below 86 degrees Fahrenheit typically become males, while those incubated above that temperature usually become females. It will take years for the hatchling turtles to develop secondary sexual characteristics that enable easy gender determination.
Big Headed Boys
Male western pond turtles (Emys marmorata) have larger heads than females do, and their snouts come to sharper, more acute points than those of females. The chins and throats of males are marked with white and yellow, as opposed to the dark markings found on females. The males’ necks are wider. Males have larger, thicker tail bases to accommodate their reproductive organs, which they normally keep inverted and withdrawn inside their tails.
A Long Time Coming
Many sea turtles' rate of maturity depends on environmental factors such as available food and water temperature. That's true of the western pond turtle. With that in mind, it takes about 8 years for specimens to reach maturity.
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