THURMONT -- Nowhere in Maryland is the impact of the state's burgeoning deer herd more visible than at Catoctin Mountain Park.
Thought to be capable of supporting 125 to 175 deer, the heavily wooded, 5,700-acre mountain preserve in Frederick County is under assault from an estimated 400 to 800 hungry deer.
The damage isn't immediately visible to casual visitors. In fact, except for the Camp David presidential retreat, Catoctin is probably best known for its abundant deer. More than a half-million people visit the national park each year, many just to catch a glimpse of deer.
"No animal has better public relations," says John Howard, a 37-year-old national park ranger and wildlife management specialist at Catoctin.
"They are beautiful, serene, useful animals. But people don't realize what damage they can do."
In the past decade, Maryland's whitetail deer have multiplied so fast that many people now regard them as pests. The population probably exceeds 150,000, and in some areas the swollen herds are destroying the balance of nature.
Howard says the damage the deer have inflicted on Catoctin's vegetation and wildlife sends a warning to other parts of the state where deer are on the increase.
There is hunting on private lands surrounding the park, and in the adjacent Cunningham Falls State Park. But deer in Catoctin multiply unchecked by hunters or natural predators.
A study by two wildlife scientists, Robert J. Warren and Charles R. Ford of the University of Georgia, concluded that the overabundance of deer could eventually destroy the forested ecosystem of the park.
Already, hungry deer eat everything palatable up to a "browse line" about 4 1/2 feet above the ground. The absence of green below the line is so striking that many visitors believe park rangers trim the foliage.
Moreover, the deer have stripped and eaten long pieces of bark from young elm trees, exposing the elms to fungal and insect infestations.
"We now estimate there are 250 bark-stripped trees in the park, probably more," says Howard. "We're probably looking at the death of 90 percent of the park's elms within five to seven years."
By consuming both plants and seedlings, the herd threatens other species as well: wildflowers, shrubs such as rhododendron and wild azaleas, and even the big hardwood trees that dominate Catoctin.
"If it continues like this, the whole ecosystem of the park will change," says Howard. Much of the tree cover will disappear, he says, and Catoctin "will turn into what they call in the South a 'bald grassy meadow.' "
Long lists of wildflowers noted in a 1985-86 survey, such as lady slipper and trillium, can no longer be found in Catoctin.
The loss of tender plants, seeds and ground cover already has driven many small animals and songbirds from the park and reduced the population of wild turkeys from about 230 in 1983 to around 35 now.
The deer themselves are in sorry shape, says Howard. They are emaciated, their growth is stunted and their coats have no sheen. Birth rates are down, the deer have inadequate fat reserves in winter and they are plagued by tumors and parasites.
In their search for food, the deer are walking out of the park to browse in neighboring wheat fields and apple orchards. Local farmers have lost up to 25 percent of their crops to deer.
Park authorities are caught between the long-standing pleas of farmers to cull the Catoctin herd, and a perceived threat of lawsuits and demonstrations by animal-welfare advocates if hunting is allowed inside the park.
A committee of state and federal wildlife officials, scientists, fruit growers, and animal-welfare representatives is now considering National Park Service recommendations for dealing with the deer.
The proposals include the fencing of threatened plants, increasing hunting on lands surrounding the park and, as a last resort, the shooting of deer inside the park by rangers. A series of public hearings on the recommendations probably will be held this spring.
A controlled hunt by park rangers would be ordered only if five years of monitoring determined that the deer were continuing to cause long-term damage to other animal and plant populations.
But relying on hunger and disease to reduce the deer population is "not going to be pretty," says Howard. "They're going to die in the park, but also in people's front yards and in downtown Thurmont."
Nonetheless, the National Park Service hopes to avoid a major dispute with animal-welfare advocates over hunting. The controversy no doubt would lead to litigation and delays, and Catoctin would become a test case for deer problems on federal land nationwide.
For now, "we're proposing to see whether natural processes will help us," says John Hadidian, a wildlife biologist for the National Park Service. He says the poor condition of Catoctin's deer "seems to indicate the deer population may be limiting itself."
But other scientists, fruit growers and Catoctin's superintendent disagree with the idea of letting nature solve the problem.