San Diego Natural History Museum--Your Nature ConnectionSDNHM Field Guide
Pacific Pond Turtle, photographed at Barrett Lake, SD County, by Jim Melli

Clemmys marmorata
Pacific Pond Turtle

EMYDIDAE

Clemmys in Greek means turtle; marmor is Latin for marble.

Description

The Pacific Pond Turtle reaches a length of 7 1/2 inches (187.5 mm).

This species varies in color from dark brown and olive to black with a radiating pattern of spots on the carapace shields. The plastron is yellowish. Other than its olive-drab appearance and relatively flat profile, this turtle has no notable features.

Subspecies: Two subspecies have been recognized: the Southern Pacific Pond Turtle (C. m. pallida) and the Northern Pacific Pond Turtle (C. m. marmorata). The Southern Pacific Pond Turtle subspecies occurs in this region.

Range and Habitat

The Pacific Pond Turtle ranges from the state of Washington, south along the Pacific slopes and interior valleys into northPacific Baja California. It is San Diego County's only native freshwater turtle.

It lives where water persists throughout the year -- in ponds along foothill streams or in broad washes near the coast where water is concentrated from back country streams. The ponds favored by turtles are characterized by various emergent and floating vegetation such as cattails and mats of algae. These islands of vegetation are usually large enough to ensure a fair supply of food and protection for the pond turtle.

Natural History

Behavior: When undisturbed these turtles will sun themselves on rocks protruding from the pond or on partially sunken logs. Sometimes, they float on large patches of green algae. At the first sign of danger, they quickly splash into the safety of the pond, where they become invisible to predators.

In years past, San Diego's Mission Valley supported a large population of these turtles. Due to human encroachment, populations in the valleys and along the coast appear to be less stable than those away from urban sprawl. In some cases populations are enhanced by artificial reservoirs and farm ponds.

Prey and Predators: Their diet includes small fish, frogs, various aquatic insects, and some plants. Insects are the best represented group of animals in ponds, and make up a large part of the pond turtle diet. The larvae and nymphs of caddisflies and dragonflies probably serve as an important food source.

Predators include raccoon and coyotes. Young turtles are preyed upon by a wider range of creatures, such as raptors, ravens, weasels, and large fish species.

Breeding: In mid to late spring, the turtles breed and lay up to eleven eggs in a clutch. The female deposits her eggs in sand or loose soil, usually near the pond. Hatchlings appear in about 12 weeks.

Conservation Status

The Pacific Pond Turtle is currently a Federal Special Concern species (FSC) and protected as a California Special Concern species (DFG-CSC).


Text by Dick Schwenkmeyer.
Photo by Jim Melli.

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