Raccoons scourge of turtle young in northeastern Ohio (Steve Pollick)

THE BLADE (Toledo, Ohio) 15 June 08 Raccoons scourge of turtle young in northeastern Ohio (Steve Pollick)
Seventeen rare Blanding's turtles were released last week into the 465-acre Sheldon Marsh State Nature Preserve, hard by Lake Erie in Erie County.
Wish them well. Their kind has been walking around with bull's-eyes on their backs for years, and raccoons are the predators that have had them in the crosshairs.
The turtles released this week have been raised in captivity for three years and now are thought to be large enough to better survive the raccoon threat -being bigger and tougher than a mouthful of egg or a hatchling.
The development is the result of a fortuitous union of field researchers, naturalists, conservationists, and fur trappers who have pooled their talents to devise a plan to keep these declining but interesting turtles in their niche in northern Ohio marshlands.
The Blanding's is a medium-size turtle, about seven to nine inches long and weighing a half to three-quarters of a pound. It is readily told by its bright yellow neck and boxlike shell having pale yellow spots.
Though its range nowadays includes scattered populations in the Canadian Maritimes and across the Northeast, Midwest, and northern prairies in the United States, the Blanding's has been in decline because of losses and threats to wetlands, it primary habitat, plus illegal collecting. In Ohio it is found today only in wetlands in Lucas, Ottawa, Erie, and Cuyahoga counties.
Now, after years of field research that has included radio-tracking pregnant female turtles, researchers from the Cleveland Metroparks and Ohio Division of Natural Areas and Preserves have figured out that raccoon predation is a major problem in the decimation of remaining Blanding's populations.
"We literally were seeing 100 percent losses of every nest we observed," said Gary Obermiller, north regional manager for DNAP. "Every one was raided and destroyed that same evening [on which the eggs were laid]. Raccoons were just scenting these turtles like a beagle on a rabbit."
As a result of the research, DNAP is widening its scope of concern. "We're looking at our wetland preserves where we have diverse and abundant turtle populations like the spotted turtle, a listed species." Obermiller also is concerned about the painted, snapping, and map turtles - "even these common species, they're all at risk."
Among the state nature preserves getting DNAP's attention are Irwin Prairie in western Lucas County and Sheldon Marsh. Several other sites in Lake, Portage, and Clark counties also are on the management list.
"We noticed there was a recruitment problem with the Blanding's turtle at Sheldon Marsh in particular," said Obermiller. "We weren't seeing any young turtles." Similar problems were seen at the Cuyahoga Valley National Recreation Area.
Working under a grant from the Ohio Office of Coastal Management, field researchers from the zoo's natural resources division trapped pregnant female Blanding's turtles from several sites at Sheldon, and collected and incubated the eggs, raising the hatchlings at the zoo for a year 'to get them to a good size."
Other sites included in the field work were the private Winous Point Marsh Conservancy in Ottawa County, the Ohio & Erie Canal Restoration in Cuyahoga County, and Mentor Marsh State Nature Preserve in Lake County.
Researchers attached miniature radio transmitters in backpacks to the young turtles. "They were glued right to the shell." Then the hot-wired turtles were released near the nests where they originated, along with captive adult females. Tracking the turtles helped outline their habitats, hibernation sites, food sources, and survival rates.
The conclusion was that nest predation and predation of young by overabundant raccoons was a major problem. So was roadkill, in which turtles migrating short distances would be crushed by passing motor vehicles. A Blanding's may cover a half-mile or more in its wanderings.
"Researchers saw turtles dying in a multitude of ways," Obermiller said. But he said that specific work by self-employed biologist Greg Lipps fingered the raccoons. Lipps, based in northwest Ohio, does contract work for various conservation agencies and organizations statewide.
"Greg made us aware that raccoon predation of these turtles nests definitely was a factor in young turtle survival. He recommended removal of some raccoons."
As a result, Obermiller said, "we are working with local trappers to effectively manage our raccoon population during furbearing [trapping] season." Last fall at Sheldon, trappers took 38 raccoons alone.
This spring is the first season that DNAP staff at Sheldon has seen young snapping turtles on the beach there. Obermiller said that it cannot be said for sure after just one season that the raccoon removal is the reason behind the presence of young turtles, but it looks suspiciously coincidental.
"What will really tell the tale are the turtles that are starting to nest right now. We're going to monitor the predation rates of those nests.
"This is a big thing nationwide," Obermiller added. "Organizations like ourselves, The Nature Conservancy, and others have been managing plant species and ignoring [management of] the animal species. It's a biodiversity approach. We've always prided ourselves on that but we've not done a good job of following up ourselves."
Lipps could not agree more. "It's really the future of a lot of this," he said of management needs of preserved habitats. We're going to have to do more management of wildlife, not just the plants."
A parallel problem is the impact of overabundant white-tailed deer in unhunted populations; the deer eat every plant in sight, endangered or not, up to a "browse line," which is measured by as high as they can stretch their necks.
On the raccoon-turtle issue, Lipps noted that museum specimens of turtles show predation marks on shells - "two perfectly spaced canine tooth indentations on the shell." The toothmarks perfectly match the raccoon jaw. Still, Lipps noted, an adult turtle survives the raccoon attack; the eggs and young do not.
The problem, moreover, is not readily apparent to the casual eye, Lipps said. "Turtles have long lives and oftentimes you will see individuals in a population long after the population has in effect become extinct." That is because of no survival among hatchlings or eggs on nest.
Lipps cites research that shows that urban and suburban raccoon populations are much higher than rural populations. "I think this is the important point - the increased suburbanization of our state and encroachment [by development] upon natural areas has led to the artificially high raccoon densities.
"We caused the problem and we need to fix the problem. This isn't our granddaddy's predator control - killing predators out of fear and ignorance. This is taking responsibility for the problems we have created."
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