Western Pond Turtle

Actinemys marmorata

Western Pond Turtle

Actinemys marmorata
Other Common Names
Pacific Pond Turtle
Other Common Names
Pacific Pond Turtle

At the Aquarium

Presentation Spaces

Appearance

The upper shell of western pond turtles range in color from brown to black with lighter marbling. The lower shell is black and yellow. The head and legs are dark with possible yellow markings.

Males have a light or pale yellow throat, whereas females have a brownish throat with dark marks. Males tend to have a longer tail than females. Male’s shells are also usually flatter and less marked than female’s.

The western pond turtle grows to lengths of 15 to 20 cm and weighs 1 to 2.4 pounds. Hatchlings are about one inch in shell length.

Habitat

Streams, ponds, lakes, and wetlands.

Diet

Variety of insects, tadpoles, frog eggs, snails, leeches, aquatic beetles, dragonfly larvae and fish. They also eat filamentous algae, lily pods, tule and cattail roots.

Life History

Western pond turtles spend most of their lives in water, but they also need terrestrial habitats for nesting. They also prefer habitats with logs and boulders where they can bask in the sun.

Mating occurs in the spring and sometimes fall. Nesting typically takes place from late May through the middle of July. Females dig a hole for the nest, usually in an area with dry soil and sparse vegetation. The female first softens the soil with urine then scoops the soil out of the nest using her hind feet.

Once the nest is prepared, the female lays 3 to 13 eggs. The hole is then filled with vegetation and dirt and covered with wet soil. The eggs incubate in this humid underground environment for 90 to 130 days.

In the wild the western pond turtle lives up to 50 years. This species reproduces relatively slowly, with turtles reaching sexual maturity between 7 and 12 years of age.

IUCN Status

Vulnerable

Ecosystem & Cultural Importance

Western pond turtle populations are in decline due to disease, habitat loss, degradation of nesting areas by invasive plants, as well as the introduction of predators. Invasive bullfrogs and the introduction of warm freshwater fish (like bass) are the biggest threats to this species. Both the bullfrog and bass prey on small juvenile turtles. Raccoons are also predators, particularly at the edges of urban areas and around campgrounds.

Western pond turtles are important to the overall health and biodiversity of the ecosystems they inhabit. At all life stages they are important prey for natural predators and they are also consumers of a variety of plants and animals.
From the Puget Sound lowlands in Washington through Western Oregon and California, south to Baja California, Mexico.
The western pond turtle lives in areas primarily west of the Cascades. The largest populations in Oregon are found in the Willamette, Umpqua, Rogue, and Klamath River drainages. They are classified as an Oregon Conservation Strategy Species in the Coast Range, East and West Cascades, Klamath Mountains and Willamette Valley ecoregions. Strategy Species are species of greatest conservation need.
The western pond turtle is one of the two native turtle species in Oregon. The other native turtle species is the western painted turtle.

Aestivation is the summer equivalent of hibernation where animals become dormant to escape harsh conditions in their environment. In Oregon, the western pond turtle is known to aestivate on land during periods of hot dry weather.

Citations & Other Resources

  • Tortoise and Freshwater Turtle Specialist Group. 1996. Actinemys marmorata (errata version published in 2016). The IUCN Red List of Threatened Species 1996.
  • U.S. Fish & Wildlife Service. N.d. Western Pond Turtle. https://www.fws.gov/species/western-pond-turtle-actinemys-marmorata
  • Oregon Department of Fish & Wildlife. N.d. Western pond turtle. https://myodfw.com/wildlife-viewing/species/western-pond-turtle
  • Seattle Audubon Society., H.A. Brown, R.M. Storm, and W.P. Leonard. 1995. Reptiles of Washington and Oregon. Seattle Audubon Society.
  • Oregon Conservation Strategy. 2016. Oregon Department of Fish and Wildlife, Salem, Oregon.
  • St. John, A. D. 2002. Reptiles of the Northwest. Lone Pine Pub.
  • Oregon Department of Fish and Wildlife, Port of Portland (Or.), and Oregon Native Turtle Working Group. 2015. Guidance for conserving Oregon’s native turtles including best management practices. Oregon Department of Fish and Wildlife.