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July 5, 2004
Western pond turtle 520 is beeping. Or, more precisely, the radio transmitter glued to her shell is transmitting and Chris Soto, holding a small antenna, is picking up the sound on a telemetry receiver, telling him that the adult female turtle is in a nearby lily-rich pond. So far, turtle 520 appears to be staying in the pond at Elijah Bristow State Park where she was trapped and fitted with a radio transmitter this summer. One of six sending signals back to Soto and Kat Beal, a U.S. Army Corps of Engineers biologist, No. 520 seems to be finding what it needs to survive in the stretch of ponds and slough that were once a channel of the Middle Fork of the Willamette River. The ponds are a kind of turtle heaven: plenty of vegetation for cover and half-submerged logs for basking in the sun, a necessity for the reptiles that need the warmth to get their metabolism moving. "But I wouldn't be surprised if half of them moved to Lost Creek," Beal said. Even though the nearby creek water is cooler, turtles have been seen there before, she said. Beal and assistant Soto are studying the Western pond turtle, one of two turtle species native to Oregon but dwindling in the watery habitat where they once thrived. Nobody knows just how many turtles once inhabited the state, but populations may have reached as high as 100,000, Beal said. There's nowhere near that number today. The best guess for the Willamette Valley these days is about 5,000. "They were probably once really common" here, said Beal. "Now they're pretty uncommon." At Elijah Bristow State Park, volunteers are helping Beal and Soto track a small population of perhaps 40 turtles to learn more about how they're doing and where they nest for breeding and wintering. In addition to the six transmitting their location, 20 others have been marked with fingernail polish dabbed on their shells. Initial observation shows that the turtles are nesting near the park's ponds. "We followed one turtle to a nest site that she dug but later abandoned, indicating that the habitat in the vicinity of the nest was probably suitable," Beal said. The effort is part of a larger restoration project at Elijah Bristow, an 870-acre wonder of river, stream, meadow and riparian forest tucked away off Highway 58. The day park is beloved by horseback riders, birders, anglers and picnickers. Elijah Bristow is home to elk, deer, chinook salmon, trout, kingfishers, woodpeckers, red-tailed hawks and dozens of other species. But hardy invasives such as blackberry and Scotch broom have been choking the plant diversity out of the park for decades. The restoration project, overseen by the Middle Fork Willamette Watershed Council, seeks to bring back some of that diversity with help from a $60,000 Oregon Watershed Enhancement Board grant and $15,000 from Oregon Parks and Recreation. The three-phase effort began last winter when volunteers planted more than 1,000 native trees in a 3-acre section of the park. Black cottonwood, big-leaf maple, red alder, Oregon ash and incense cedar saplings just a few feet high now dot an open meadow south of the Middle Fork. That section is part of a broader 27-acre section that once was riparian forest, said project manager John Moriarty. Aerial photos from 1936 and 1954 show the forest as it was, but by 1968 the trees had been cut and the land used for agriculture, he said. When farming ended sometime in the 1970s, a result of statewide efforts to add more parklands to the public roster, the invasive plants moved in and took over. The new saplings have required some tender loving care to get established. They are wrapped in blue plastic sleeves to protect them from small gnawing mammals, and Moriarty designed a solar-powered pump and drip irrigation system to keep them well-watered throughout the dry summer months. Re-establishing the forest should help shade out the invasives, said Moriarty, giving native plants such as wild rose and snowberry the chance to thrive again. "This isn't about eliminating the invasive species. It's about establishing a balance that favors the natives," he said. When the park staff mowed the meadow before the trees were planted, Moriarty noticed that several natives, including the snowberry - a deciduous shrub with pea-sized flowers and blueberry-shaped white fruit - had survived under the great roping blackberry vines. As the first phase of the project winds down, volunteers will begin working on a restoration design for the remaining acres. But that planning won't be complete until the turtle researchers have collected more data, said watershed council coordinator Amy Chinitz. "We don't want to slap down a bunch of trees and find we've disturbed some turtle habitat," she said. Chinitz said people can get used to all the changes made to the land and forget the wonder of seeing an area in a restored state. "We've done a lot of things to alter landscape and make habitats less healthful for fish and wildlife," she said. "This is an attempt to make up for damage that we've done." TO GET THERE Elijah Bristow State Park: Traveling east on Highway 58, turn left on Wheeler Road a few miles east of Pleasant Hill. Park highlights: 847 acres of meadow, woodlands and wetlands along the Middle Fork of the Willamette River just west of Dexter Reservoir. The park includes 10 miles of trails that skirt the river, Lost Creek and a series of small ponds. Look for basking turtles on sunny mornings in ponds with partially submerged logs. Noise spooks the skittish reptiles, so approach quietly. Cost: No fee to use the park, except for group shelters, which can be reserved at $35 per day for 50 people. For information, call (800) 551-6949. Reservations, call (800) 452-5687. Tour: The Middle Fork Willamette Watershed Council plans a tour on July 29 from 6:30 p.m. to 8 p.m. Use the main park entrance and drive to the parking lot on the left after the Lost Creek Bridge. Restoration: To learn more about the work of watershed councils, visit www.oweb.state.or.us/groups/WSC_List.shtml
WESTERN POND TURTLE TRIVIA Long lived: Turtles live at least 20 to 30 years and don't begin reproducing until about their 13th year. Winter's nap: They hibernate, some digging shallow nests in grasslands or forest duff, others burrowing down into the mud at the bottom of a pond, where they shut their metabolism down so that breathing becomes unnecessary, as the oxygen that penetrates their skin is sufficient. They snooze from November to February. Babies: Females nest in June and July, preferring warm clay soil to dig shallow nests where they deposit three to 13 eggs, about an inch long. The young hatch in September, but most stay in the nest throughout the winter to emerge the following February or March. The eggs and young are vulnerable to predators such as foxes and raccoons. Those that survive and make it to water without being eaten spend their first year in shallow ponds feeding on insects and larvae. Heat and gender: The warmth of the nest determines the sex of the turtle. In the warmest nests, the young are all female; in the coolest, all male. In middling warm nests the young are a mix of male and female. Threats: Western pond turtles have been declining primarily because of loss of habitat, and predation by large-mouth bass and bullfrogs, introduced species that target young turtles. The only effective natural predator of an adult turtle is the river otter. Thriving pockets: Researchers have found successfully reproducing populations near the confluences of the Willamette and McKenzie rivers, and the Middle and Coast forks of the Willamette River, the Kirk Pond-Coyote Creek area near Fern Ridge Lake, and the upper reaches of Hills Creek Reservoir. Large populations exist in sloughs and ponds along the Willamette in the southern and central valley and in smaller numbers along the Long Tom, Calapooia and Luckiamute watersheds. The U.S. Army Corps of Engineers manages pond turtles at Fern Ridge, Fall Creek, Hills Creek, Lookout Point and Dorena lakes. Leave them be: If you see a pond turtle away from a pond in June or July, it almost certainly is a nesting female. In spring and fall, turtles are moving to and from wintering nests. Unless it is in imminent danger - on a road, for example - leave it alone. - U.S. Army Corps of Engineers biologist Kat Beal
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