Actinemys marmorata Western Pond Turtle
Some other names for this species:
Pacific Pond Turtle
Pescadero Marsh Natural Preserve, San Mateo County, CaliforniaJuly 25, 1998
Western Pond Turtle (Actinemys marmorata)
There aren't too many places along the California coast where it's easy to find turtles anymore, but Pescadero Marsh still has a healthy population.

This species was until recently considered part of the genus Clemmys.

Andrew Molera State Park, Monterey County, CaliforniaSeptember 17, 2000
Western Pond Turtle (Actinemys marmorata)
This tiny little guy was just a couple of inches across. It was sunning itself right near the edge of a river, keeping a wary eye on my camera and tripod. When I got too close, it would swim down to the bottom for a few minutes.
Oso Flaco Lake, San Luis Obispo County, CaliforniaFebruary 23, 2002
Western Pond Turtle (Actinemys marmorata)
Any day upon which you see wild turtles is a happy day, and this was no exception. We saw 8 or 9 adult turtles on the edges of Oso Flaco Lake, basking in the sun. Unfortunately they were all pretty far from us, so I couldn't get a very good photo.
Henry W. Coe State Park, Santa Clara County, CaliforniaFebruary 17, 2007
Western Pond Turtle (Actinemys marmorata)
On a warm winter day, my friend Fred Harer and I were pleasantly surprised to discover a pond with quite a few pond turtles drifting about.
Henry W. Coe State Park, Santa Clara County, CaliforniaJuly 15, 2013
Western Pond Turtle (Actinemys marmorata) Western Pond Turtle (Actinemys marmorata)
The same pond a few years later had several pond turtles hauled out on partially submerged logs. They were very difficult to approach closely; they would slip into the water the instant they were aware of my presence.
Santa Cruz County, CaliforniaJuly 26, 2013
Western Pond Turtle (Actinemys marmorata)
James Maughn showed me this pond in which native and non-native turtles commingle. In this photo, the second turtle from the left is a Red-eared Slider, and the other four are Western Pond Turtles.
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