Photo courtesy of US Fish & Wildlife Service
By Bob Garrison
Outdoor California -- May/June 1998
Nothing represents the approaching days of summer better than a line of western pond turtles basking in the sun atop an old snag. These cold-blooded reptiles spend much of their day regulating their body temperature. In cool weather, they leave the water to bask in the sun at favorite basking sites. During hot weather, they float in the cool water. The turtles spend most of their lives in the water, but need well-drained silty soil to lay their eggs. The female will travel over 400 meters to find suitable nesting sites in upland areas away from the water. In late spring, one to 13 eggs are laid in a shallow hole which is then covered with dirt. Nests are highly susceptible to predators as well as to trampling by cattle or people. The western pond turtle is the only native turtle that lives in California. It ranges from Washington to Baja California.
Once a common site along most low elevation ponds and streams, the western pond turtle is quietly disappearing from the California landscape. Over 90 percent of the freshwater ponds, marshes and year-round streams where the turtles once lived have been drained, diverted or developed. Where the turtles can still be found, many populations no longer produce offspring, the result of disturbed nesting grounds and the predation of you turtles by non-native bullfrogs and black bass. With a life span of over 40 years, the presence of turtles may be a false indication that populations are healthy. As a result, western pond turtles have been classified as a species of special concern and require careful monitoring.
Finding western pond turtles can be a challenge. Beyond their declining population, western pond turtles look similar to many types of non-native turtles that now live in California's waterways. The turtles commonly seen in city park ponds are most likely painted turtles, slider or spiny softshell turtles. These mid-west and east coast species were once sold in pet shops and many were released in ponds when they grew too big for their aquarium. When you spot a turtle basking in the warm sunshine, use a good pair of binoculars to look at its head. Western pond turtles have a blunt nose and black spots or blotches on the light-colored head. Sliders and painted turtles have similar shaped heads but have light stripes or whorls on a dark head. The spiny softshell turtle has a pointed nose.
As a wildlife viewer, you can help the turtles a number of ways. First, watch from a distance. Stay back so you don't scare the turtles from their basking areas. Do not create a path to the water's edge. Raccoons, skunks, cats and other predators will use your trail to hunt for nest sites. Keep track of the locations and numbers of western pond turtles you observe. In particular, watch for young turtles to determine if the population is successfully breeding. Keep land managers informed of your observations.