Bully Plants and Creatures Victimize State Park : Pennsylvania: Presque Isle on Lake Erie draws almost as many visitors as California’s Yosemite. But this sand spit is suffering most from an invasion by non-human species.

Bullies are sneaking up on Presque Isle State Park by land, sea and air, and they’re unwilling to negotiate with the locals over turf.

The newcomers are, by and large, the black sheep of Mother Nature’s brood. Species from zebra mussels to a fast-spreading swamp reed are running amok, experts say.

These hardy species have park managers and biologists worried about irreversible changes to the makeup of Presque Isle, a popular park jutting into Lake Erie from northwestern Pennsylvania.

And they are prompting debate about what, if anything, should be done to stop them.

Presque Isle, a 7-mile sand spit, is coveted not only for its beautiful beaches but also for its varied flora and fauna. Nearly half of Pennsylvania’s rare plants can be found here.

“We would give our eyeteeth for a place like this,” said Roger Tory Peterson, the respected author of the Peterson’s Field Guide bird books.

Presque Isle nearly outdrew Yosemite National Park in California last year, with each attracting about 4 million visitors.

The masses are most likely unaware of the invasions taking place around them.

But Jim Bissel notices.

The botanist from the Cleveland Museum of Natural History toured the park with other plant experts recently to investigate the spread of three exotic species--phragmites (frag-MITE-eez), canary grass and Japanese bush honeysuckles.

Many familiar with the park agree that exotic plants are the biggest threats. They rob smaller plants of light and nutrients and dominate acres of land at a time.

Native plants in trouble include the twig rush, Smith’s bull rush and variegated horsetail.

Phragmites--”frags” for short--are among the most visible invaders. The plants reach twice the height of adult humans and can extend roots the size of electrical cables beneath a paved road in one growing season. They already have taken over Dead Pond, which is among the park’s largest bodies of water.

Frags have spread rapidly through Presque Isle since an Erie resident recruited Boy Scouts to plant them as a beautification project in 1971, said Evelyn Anderson, a columnist who is writing a book about the park.

Canary grass also is conquering land, most noticeably near the park entrance, where it resembles fields of wheat.

“First it comes in here in a spot, then there at a spot, and pretty soon it’s an entire meadow,” Bissel said.

The hardy Japanese bush honeysuckles throw nature out of whack because deer dislike them. That gives the exotic plant an advantage over native honeysuckle, which the deer love.

The biggest problem with the spread of exotics, Bissel said, is the elimination of species that have been in the park for centuries. Presque Isle is home to nearly half of the five dozen rare, endangered or threatened plant species in Pennsylvania.

One expensive and controversial tactic supported by Bissel would be wiping phragmites or canary grass with herbicide-soaked sponges. But state parks official Greg Schrum said some environmentalists oppose the introduction of chemicals at Presque Isle.

Without intervention, Bissel said, Presque Isle could end up like the Lake Erie coasts of western Ohio--in his words, “phragmites, phragmites, phragmites, phragmites.” He said exotic plants should be stopped before they eliminate the park’s native species--thinking that contradicts the notion of “only the strong survive.”

“If they gave me a bulldozer for two weeks, I tell you this park would look a lot different,” Bissel said.

An ambitious goal for Presque Isle would be returning its plant population to only species that lived on the sand before European settlement in the 17th and 18th centuries, said Kathy McKenna, a state plant scientist.

Threats on four legs are also catching the attention of park managers. Deer eat rare bushes and young trees, and the bigger the herd, the fewer trees will grow in the park.

Now numbering about 100, deer breed unchecked because nothing on Presque Isle preys on them, outside of an occasional car. And a bigger deer herd means an increased risk of Lyme disease from deer ticks, said Presque Isle Supt. Harry Leslie.

The waters off Presque Isle also are threatened by exotic species, said Ed Masteller, a Penn State aquatic biologist and frequent diver at the park.

Lake Erie’s Thompson Bay teems with tiny hit men of the deep--fingernail-sized quagga and zebra mussels. They piggyback on bigger shellfish and suffocate them by blocking their water siphons.

Masteller said the invading mussels, which came to the Great Lakes during the 1980s in the holds of European freighters, have reduced a dozen bivalve species, including the fat muckle, to negligible numbers.

Sunbathers cut their heels on zebra mussels that washed up last summer on Beach 11, one of the park’s most popular spots. A section of beach was closed briefly as park workers swept away mounds of shells.

Schrum, the resource management chief for Pennsylvania parks, said he sees benefits in protecting endangered species at Presque Isle from intruders who otherwise would almost certainly prevail. Bissel is planning to recruit college students to rip out some plants by next year.

But he is cautious about what good humans can do and whether they would only be delaying an inevitable result.