National Park superintendent: 'I don't think there are rabbits' in prairie area prepped for summer restoration work
July 28, 2010 · Updated 3:07 PM
The National Park Service sprayed the herbicide Roundup over a three-acre area of the American Camp prairie in June, in preparation for a prescribed burn and planting of native grasses.
That's according to Peter Dederich, the National Park superintendent, as he prepared for a public meeting Tuesday on the proposed removal of European rabbits as part of the prairie restoration plan. The burn was postponed because of dampness and, later, because of wind. Dederich expects the burn will take place in September.
Dederich said he didn't expect that the spraying had any effect on rabbits in the sprayed area, because he believes the rabbits had moved. Before the spraying, the area was checked for Island Marble butterflies, a rare species once believed to have been extinct, and for foxes, he said.
"I don't think there are rabbits in that area," Dederich said. "They have been gone from that area, we think, trying to avoid predation. On the gravel path to the parade ground and the laundress's quarters, there are scads of rabbits."
Several studies conducted between 1998 and 2009 showed Roundup's active and inactive ingredients can inhibit the production of endocrine and progesterone in mice and rats, and can cause genetic damage in mice. It's lethal to aquatic animals.
The three-acre area is separated from surrounding grasses by a mowed strip. Dederich didn't know when the strip was mowed, but on the morning of July 24 tire tracks were visible to the area from Pickett's Lane, about midway between the beach parking lot and the road to the redoubt. No rabbits were visible in the area, although seemingly fresh rabbit droppings were visible near burrows. In one spot next to a rabbit fence, rabbit fur seemed to indicate a recent predator/rabbit encounter.
The rabbit population is at its lowest since 1985, according to National Park rabbit population counts. The population in winter 1973 was estimated at 8,400 on 827.8 acres of prime habitat, and 1,700 on 415.1 acres at American Camp. The population in spring 2005 was estimated at 1,818 on 173 acres of prime habitat at American Camp. University of Washington's College of Forest Resources estimated the population on those 173 acres as between 95 and 330 in 2009 and 414-884 this year.
The National Park has used rabbit fences to keep the rabbit population at bay. But before and during Tuesday's public meeting, islanders questioned the impact of herbicides on the rabbit population — and expressed concern that the elimination of the rabbits was already under way. One proposal is to eliminate the rabbits by shooting; that has been most alarming to rabbit fans. Another proposal is to continue the current course of management, which the National Park says inhibits work to restore the prairie and protect habitat for sensitive species.
Keith Van Cleve is a forest ecologist and wildlife photographer whose picture of an Island Marble butterfly nectaring on American Camp mustard has been widely published. He said he stopped visiting American Camp because "I got tired of seeing all the death." During one walk, he saw National Park workers spraying herbicide on blackberries while hummingbirds flittered nearby. He's seen very few rabbits.
"The thing that amazes me is, they say rabbits are burrowing into both sides of the redoubt. The only thing I've seen are fox kits and family of foxes, in and out of three holes there."
Tempers flared at the meeting Tuesday, and resident Linda Blue stepped in as mediator. But some possible alternatives did emerge.
Sandi Ackerman of Rabbit Meadows Feral Rabbit Sanctuary in Seattle said the American Camp rabbits could be trapped, neutered and released back into the wild; or trapped, neutered and relocated to the sanctuary. She said a neutered rabbit population would die off naturally within a couple of years. "It's a humane option," she said.
Others said sensitive areas could be protected with rabbit fences.
European rabbits are believed to have been introduced to the island as a food source between 1875 and 1895. They were hunted through the mid-20th century, and Sports Illustrated featured the sport of San Juan Island rabbit hunting on Sept. 28, 1964.
The National Park Service says the rabbits prevent native grasses from flourishing on the prairie, which in turn destroys habitat for sensitive species such as the Island Marble butterfly. The butterfly was believed to have been extinct until its re-discovery on the prairie in 1998. The butterfly has disappeared from Canada's Gulf Islands, its habitat destroyed by grazing.
National Park officials say rabbit burrows also threaten cultural resources like the redoubt, a fortification built by U.S. troops during the joint military occupation of 1859-1872.
Opponents of the rabbit removal plan say the rabbits' removal will disturb the ecosystem that is in place now, and would remove a food source for eagles and foxes.
Jackie Scherer said that while the charge of the National Park is to preserve and interpret the history of American Camp as it was from 1859-1872, the site had been a sheep farm before U.S. troops arrived. "The whole place was a disturbed area to begin with," she said. "It wasn't a pristine prairie."
Richard Weisbrod, a retired professor at U.W.'s College of Forest Resources, is listed as co-author of "The Rabbits of San Juan Island National Historical Park," published by the National Park in the mid-1970s. Weisbrod said his graduate student and co-author, W. Frederick Stevens, was the primary author. Janet Thomas held the book up at the public meeting, and made note of the section titled "The Art of Rabbit Watching."
Weisbrod believes native grasses and rabbits can co-exist. "Native grasses have had lots of different herbivores feeding on them — deer, squirrels, mice, rabbits. They are adapted as grasses to tolerate pretty heavy predation. Oak trees don't do that, pines and firs don't do that either, but grasses do."
Weisbrod agrees that rabbits have altered the landscape. "But have they altered the landscape any more than people have altered the landscape? They have been here long enough to be part of that ecological system. It's not a wise idea to try to eliminate them. The National Park can manage them where they occur by fencing off the sensitive areas."
Prairies are increasingly rare in Western Washington. All told, the American Camp prairie is about 600 acres, almost the same size as Mima Mounds Natural Area Preserve in Littlerock. Mima Mounds is managed by the state Department of Natural Resources.
Hannah Anderson, who coordinates the recovery of rare species for the Nature Conservancy, said "not more than 3 percent of the historic extent" of Washington's prairies exist today, gone to make way for agriculture and development.
Anderson said prairies are important because they are home to rare and declining species, including animals, insects and plants that only live on prairies. Prairie grasses help sustain some of the world's oxygen. "There's a huge biomass in grasses," she said
"Each prairie is its own special system. When we have so little left, we have to conserve what remains."
The next step: You can submit comments to the National Park by Aug. 12 (an earlier story incorrectly said Aug. 10 on the National Park's Planning, Environment and Public Comment website or by mail to Superintendent, San Juan Island NHP, P.O. Box 429, Friday Harbor, WA 98250.
To view and download the environmental assessment, visit the Planning, Environment and Public Comment website.