Western Pond Turtles:

Habitat and History in Oregon

History of the Western Pond Turtle:
The Western Pond Turtle is native to the Pacific Coast of the United States. Its historical range is from the Puget Sound area in Washington to Baja California. There are two sub species of the Western Pond Turtle: the Southwestern Pond Turtle (Clemmys marmorata pallida) which occurs from Monterey Bay southward, and the Northwestern Pond Turtle (Clemmys marmorata marmorata) found north of the Sacramento Valley.

While the Western Pond Turtle still inhabits the same historical range, their population within the range has declined dramatically.  There are several reasons for the decline in the species.
Turtles are at risk of predation from both wildlife and domestic pets.  They are easily killed by cars on roads, and are losing prime nesting sites due to human development.  In addition to this, non-native plants have altered terrestrial habitat, and prime waterways have been dammed, diverted, and/or polluted. 

Estimating the overall health of Western Pond Turtle populations is difficult due to both the turtles' long lifespans and the difficulties associated with locating and tracking individuals while they are nesting or hibernating.

The greatest danger facing Oregon's Western Pond Turtle population is low juvenile recruitment. The species requires accessible upland nesting habitat near their aquatic habitat. Fragmentation of properties and of land-use types renders this critical habitat requirement increasingly rare. While relatively large populations of mature turtles can be observed in their aquatic habitat, the rate of successful breeding and juvenile recruitment is largely unknown and believed to be too low to maintain population numbers at their current levels. In other words, existing populations in Oregon are likely getting older and few juveniles survive to replace their numbers.