Western Pond Turtle Recovery Plan

The Western Pond Turtle Recovery Project is designed to protect pond turtles from threats. The biggest threat to Western pond turtles is American Bullfrogs (Rana catesbiana).

Life span in the wild: 7-9 years
Size: 3.5-8 inches (9-20 cm)
Weight: 1.1 lb (0.50 kg)
Habitat: freshwater ponds and lakes
Diet: Carnivore
Reproduction: Lay around 20,000 eggs in June and July. Eggs float on the surface of the water after they are laid. Eggs hatch within 3-5 days. (6)

Since bullfrogs are not native to the Pacific Northwest, native species do not have natural defenses against them and therefore are prey to bullfrogs. Young Western pond turtles are a common source of food for the bullfrog. The population of bullfrogs is large enough (due to egg masses) to consume many pond turtles, becoming their largest threat for extinction.

Under this recovery project, newly-hatched Western pond turtles are kept and raised in captivity until they reach a size where they are too large to be consumed by bullfrogs. They are then released back into the wild.

Baby Western pond turtle
Over the 20 year period that the Western Pond Turtle Recovery Project has been implemented, the Western pond turtle population has increased from 150 to 1,500.

1991: Only 150 Western pond turtles left in Washington—The Woodland Park Zoo starts working on recovery of Western pond turtles.
1993: The Western pond turtle (Clemmys marmorata) is listed as an endangered species in Washington.
1999: The Washington State Recovery Plan is written by the Washington Department of Fish and Wildlife.
2000: The Oregon Zoo joins the Woodland Park Zoo’s recovery efforts.
2000: The first Western pond turtle reintroduction site in the Columbia Gorge is formally identified.
2000: At this point, the Western pond turtle is wiped out completely from the Puget Sound are, but two small populations of the Western pond turtle are found in the Columbia River.
2002: The Refuge and other agencies start repopulating certain creeks with the Western pond turtle with the hopes that they will no longer be endangered.
2004: WDFW and USFS develop an agreement for Western pond turtle recovery.
2005: The number of pond turtles reaches 1,000.
2011: The number of pond turtles reaches 1,500. (7, 8)

This is the figure that I created by analysing the information from two sources. The information is taken from David Hays's report on "Washington State Recovery Plan for the Western Pond Turtle" from page 8 (8), and from the Woodland Park Zoo's web page about Wester Pond Turtles (7).

Graph shows the success of WA Recovery Plan.

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