A Guide to the Amphibians
and Reptiles of California

Actinemys marmorata - Pacific Pond Turtle

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Range in California: Red

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Former Northern Subspecies

Adult female, Mendocino County

Adults, Alameda County

Adults and juveniles, Alameda County

Adult female, Contra Costa County

Adults and juveniles, Alameda County

Adult male, Kings County
© Patrick Briggs

Plastron of adult male (left)
Plastron of adult female (right)
© Pierre Fidenci

Adult, Mendocino county

Tiny juvenile, Mendocino county

Adult, Napa County © James R. Buskirk

Adult female, Butte County
© Jackson Shedd

Adult, Colusa County © Kinji Hayashi

Adults, Modoc County
© James R. Buskirk

Basking adults, Shasta County
© James R. Buskirk

Adult, Del Norte County. © Alan Barron

Adult, Napa County (showing inguinals on right) © James R. Buskirk

Adult female, Solano County
© Adam Clause.
Animal captured and handled under state Scientific Collecting Permit and released at point of capture.

Head and neck are mottled

Hatchling, Fresno County © Patrick Briggs

Former Southern Subspecies

Adult, Santa Barbara County
© Brian Hubbs

Adult, San Luis Obispo County
© Brian Hubbs

Adult male, San Luis Obispo Co.,
© Andrew Harmer

Basking adult female, San Mateo County

Hatchling, Orange County
© Jason Jones

Young male, Orange County
© Jason Jones

Basking adult male (left) and female (right), San Mateo County.

Adult female, crossing a trail in late May, San Mateo County.

Adults, Monterey County

Basking adult, San Mateo County

Adult male, San Mateo County

Adult male, Ventura County
© Patrick Briggs

Adult in habitat, Santa Barbara County
© Jason Butler

Adults basking in February, Santa Barbara County. © Brian Hubbs

Adult, Fresno County © James R. Buskirk

Hatchling, Monterey County
© Kinji Hayashi

Adult, San Luis Obispo County

Adult male, Santa Barbara County
© Jason Butler

Adult male, Kings County, (showing piebald melanism which is characteristic of males in the San Juaquin Valley.)
© Patrick Briggs

Adult male, Los Angeles County © James R. Buskirk

Hatchling, basking in situ, Los Angeles County © James R. Buskirk

Adult, Monterey County © Kinji Hayashi

Adult female, Monterey County
© Kinji Hayashi

Eggs

A. marmorata Eggs, © Patrick Briggs

Western Pond Turtle Life Cycle:
Adult, Juvenile, and Egg, Butte County.
© The Chico Turtle Lab

Identification Confusion with Melanistic Red-eared Sliders

Melanistic adult Red-eared slider - Trachemys scripta elegans, Riverside County. © Bob Parkard

Introduced melanistic sliders and old sliders whose red "ears" have faded, are often difficult to distinguish from the California native Pacific Pond Turtles, especially at a distance in the field, and even in hand. According to Bob Packard, with the Western Riverside County MSHCP Biological Monitoring Program, they confirm the identification based on the presence of large inguinal and axillary scutes on the sliders, which are absent on the pond turtles, and by an interesting behavioral clue: the majority of sliders tend to be aggressive, biting readily, while pond turtles are far more reluctant to bite.

Habitat

Habitat, river, Mendocino County

Habitat, large pond, Marin County

Habitat, forest creek, Mendocino County

Habitat with turtle, San Joaquin County
© James R. Buskirk

Habitat, large lake, Sacramento County

Habitat, small creek, Santa Clara County

Habitat, Contra Costa County

Habitat, a small pond in Alameda County

Habitat, 2,300 ft., Monterey County

Habitat, San Luis Obispo County

Habitat, Afton Canyon, San Bernardino County. According to Stebbins (2003) the turtles in this desert population may be a distinct taxon.

Habitat, San Mateo County

Adult basking on branches in pond, Contra Costa County. Where no objects are available in the water for basking, pond turtles will use branches overhanging the water, or they will bask on the shore.

San Mateo County Sign

Short Videos

Pacific Pond Turtles compete for basking space on a small pond.

Pacific Pond turtles basking in the sun.

Pacific Pond turtles in an Alameda County pond.

Description

Size

3.5 - 8.5 inches in shell length (8.9 - 21.6 cm). (Stebbins 2003) Hatchlings are aproximately 1 inch (2.5 cm) in shell length. The tail of a young turtle is almost as long as its shell.

Appearance

A small to medium-sized drab dark brown, olive brown, or blackish turtle with a low unkeeled carapace and usually with a pattern of lines or spots radiating from the centers of the scutes. The plastron lacks hinges, and has 6 pairs of shelds which can be cream or yellowish in color with large dark brown markings, or unmarked. The legs have black speckling and may show cream to yellowish coloring. The head usually has a black network or spots may show cream to yellowish coloring.
Turtles south of the Transverse Ranges tend to be lighter, from yellowish brown to light brown.

Males usually have a light throat with no markings, a low-domed carapace, and a concave plastron.
Females usually have a throat with dark markings, a high-domed carapace, and a flat or convex plastron which tends to be more heavily patterned than the male's.

Behavior & Natural History

Diurnal. Thoroughly aquatic. This turtle is often seen basking above the water, but will quickly slide into the water when it feels threatened. Seldom basks by floating at the surface. Active from around February to November. May be active during warm periods in winter. Hibernates underwater, often in the muddy bottom of a pool. Estivates during summer droughts by burying itself in soft bottom mud.

When seeking or protecting a basking spot, turtles may show aggressive behavior by opening the mouth and exposing the yellow and pinkish mouth lining to scare off another turtle. Occasionally they will also bite or ram.

Diet

Eats aquatic plants, invertebrates, worms, frog and salamander eggs and larvae, crayfish, carrion, and occasionally frogs and fish.

Reproduction

Mating occurs in April and May. Adults do not mate until they are aproximately eight to ten years old. Sometime between April and August, females climb onto land to dig a nest, usually along stream or pond margins, where they lay a clutch of 2 - 11 eggs. Some females lay two clutches in a year while others lay eggs every other year.

Range

Found along the entire western part of California, including the coast ranges and the central valley, north into Washington and British Columbia (west of the crest of the Cascades and Sierras) and south into northern Baja California (where it has disappeared throughout most of its former range.) (It may now be extinct in western Washington and British Columbia.) Isolated populations occur at Susanville. According to Stebbins 2003*, another isolated population occurs in Nevada in the Truckee, Carson, and East Walker Rivers.

Another isoloated population occurs along the Mojave River at Camp Cody and Afton Canyon where water is still present in the mostly-dry river. These turtles in the middle of the Mojave Desert are a relict population from a time many thousands of years ago when the region received more rainfall and streams that drained the mountains and flowed into the Pacific were ony a few miles from streams that fed the Mojave river, which flowed year-round. Apparently some turtles were able to cross the distance to the Mojave River drainage. (Read more about these desert turtles here - James Cornett, The Desert Sun, 6/30/12.)

Habitat

Found in ponds, lakes, rivers, streams, creeks, marshes, and irrigation ditches, with abundant vegetation, and either rocky or muddy bottoms, in woodland, forest, and grassland. In streams, prefers pools to shallower areas. Logs, rocks, cattail mats, and exposed banks are required for basking. May enter brackish water and even seawater.
Found at elevations from sea level to over 5,900 ft (1,800 m).

Taxonomic Notes

This turtle was formerly named Clemmys marmorata.

The current SSAR list does not recognize subspecies of A. marmorata, but two subspecies have been traditionally recognized: A. m. pallida, and A. m. marmorata. However, the characteristics used to define the two subspeces are ambiguous and poorly-defined and a large area of intergradation occurs in the central part of the state. Spinks and Shaffer argued that these subspecies should be abandoned because they are not supported on molecular grounds. They also showed that the current species may actually consist of up to four species, though they did not name any. (Spinks and Shaffer - 2005 Mol. Ecol. 14:2047-2064)

Janzen, Hoover, and Shaffer (1997 Chelonian Conservation Biology 2(4): 623-626) concluded that southern populations of A. marmorata, found in Baja California and adjacent southern California, are a different species from those to the north.

The Afton Canyon population may be a distinct taxon. (Stebbins 2003)

Conservation Issues (Conservation Status)

In decline in most of its range (from 75 - 80 % according to Stebbins, 2003)
Once very abundant in the southern San Joaquin Valley, with population estimates of over 3 1/3 million. Now almost extinct there.

*Pond turtles were hunted extensively in the Bay Area in the late 19th and early 20th centuries for use as food, after the release of Diamondback Terrapins into marshes in the bay was did not successfully establish breeding populations. Pond turtles replaced Terrapins in upscale restaurants until turtle meat went out of favor, possibly during Prohibition, due the use of wine in their preparation. Thousands of pond turtles were taken every year - 53,935 in 1899, alone.
(*Matthew Bettelheim - BayNature Magazine, April-June, 2010.)

Taxonomy
Family	Emydidae	Box and Water or Pond Turtles
Genus	Actinemys	Western Pond Turtles
Species	marmorata	Pacific Pond Turtle
Original Description
Clemmys marmorata - (Baird and Girard, 1852) - Proc. Acad. Nat. Sci. Philadelphia, Vol. 6, p. 177 from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz
Meaning of the Scientific Name
Actinemys - actin - ray or beam, and -emys - turtle. marmorata - Latin - marbled - refers to the marbled carapacial pattern from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz
Alternate Names
Northwestern Pond Turtle Actinemys marmorata marmorata - Northern Pacific Pond Turtle - subspecies Actinemys marmorata pallida - Southern Pacific Pond Turtle - subspecies Emys marmorata Formerly called Clemmys marmorata marmorata Formerly called Emys marmorata marmorata
Related or Similar California Turtles
A. m. pallida - Southern Pacific Pond Turtle C. p. bellii - Western Painted Turtle T. s. elegans - Red-eared Slider
More Information and References
Natureserve Explorer California Dept. of Fish and Game SDNHM James R. Buskirk has generously provided age and gender identification for many of the turtles shown here. Stebbins, Robert C., and McGinnis, Samuel M. Field Guide to Amphibians and Reptiles of California: Revised Edition (California Natural History Guides) University of California Press, 2012. Stebbins, Robert C. California Amphibians and Reptiles. The University of California Press, 1972. Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003. Behler, John L., and F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992. Powell, Robert., Joseph T. Collins, and Errol D. Hooper Jr. A Key to Amphibians and Reptiles of the Continental United States and Canada. The University Press of Kansas, 1998. Bartlett, R. D. & Patricia P. Bartlett. Guide and Reference to the Turtles and Lizards of Western North America (North of Mexico) and Hawaii. University Press of Florida, 2009. Carr, Archie. Handbook of Turtles: The Turtles of the United States, Canada, and Baja California.* Cornell University Press, 1969. Ernst, Carl H., Roger W. Barbour, & Jeffrey E. Lovich. Turtles of the United States and Canada. Smithsonian Institution 1994. St. John, Alan D. Reptiles of the Northwest: Alaska to California; Rockies to the Coast. Lone Pine Publishing, 2002. Lemm, Jeffrey. Field Guide to Amphibians and Reptiles of the San Diego Region (California Natural History Guides). University of California Press, 2006. Watch more short movies of this turtle at Endangered Species International (www.endangeredspeciesinternational.org)

Conservation Status
The following status listings come from the Special Animals List which is published by the California Department of Fish and Wildlife. Notes from the 1/11 Special Animals List: Emys marmorata western pond turtle 1) The paper: Spinks, Phillip Q. & H. Bradley Shaffer. 2005. Range-wide molecular analysis of the western pond turtle (Emys marmorata): cryptic variation, isolation by distance, and their conservation implications. Molecular Ecology (2005) 14, 2047-2064. determined that the current subspecies split was not warranted. Therefore, we are now tracking the western pond turtle only at the full species level. 2) The paper: Spinks, Phillip Q., & H. Bradley Shaffer. 2009. Conflicting Mitochondrial and Nuclear Phylogenies for the Widely Disjunct Emys (Testudines: Emydidae) Species Complex, and What They Tell Us about Biogeography and Hybridization. Systematic Biology. 58(1): pp. 1-20 determined that the correct genus name is Emys.
Organization	Status Listing
U.S. Endangered Species Act (ESA)	None
California Endangered Species Act (CESA)	None
California Department of Fish and Wildlife	SSC	Species of Special Concern
Bureau of Land Management	BLM:S	Sensitive
USDA Forest Service	USFS:S	Sensitive
Natureserve Global Conservation Status Ranks	G3G4T3 S3	Vulnerable
World Conservation Union - IUCN Red List	IUCN:VU	Vulnerable

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