Ecosystem

Interior Secretary Gale A. Norton will propose today that 28 species of snakehead fish be added to the country's list of injurious species, a move that coincides with the discovery this month that northern snakehead fish have been rapidly multiplying in a Crofton pond and feeding on native species. Inclusion on the list would prohibit the importation of the fish anywhere in the United States and would make it illegal to transport the fish across state lines, according to officials with the U.S. Fish and Wildlife Service.

BACK WHEN exterminating predators passed for wildlife management, conservationist Aldo Leopold made this plea for wolves in an immortal essay, "Thinking Like A Mountain": "I have watched the face of many a newly wolfless mountain, and seen the south-facing slopes wrinkle with a maze of new deer trails." Soon, he said, "such a mountain looks as if someone had given God a new pruning shears, and forbidden Him all other exercise. "I now suspect that just as a deer herd lives in mortal fear of its wolves, so does a mountain live in mortal fear of its deer.

CHESTERFIELD, Mo. - For nine years, two dozen genetic engineers struggled to create a simple soybean that would stand up to a killer herbicide. After tens of thousands of blind alleys, they thought they might have done it: The researchers had created 100 seedlings that contained DNA from soil bacteria, a cauliflower virus and a petunia plant. They planned to test them cautiously in their Monsanto Co. labs. But an eager executive decided to test them all, to douse every plant with a highly potent concentration of the herbicide.

The first page of Phil Hawes' Web site contains a Chinese proverb that reads: "When you hear something, you will forget it. When you see something, you will remember it. Not until you do something, will you understand it." With that spirit, Hawes, a visiting professor at the University of Maryland, Baltimore County helped the students in his summer course to design sustainable environments on regular visits to the woods on the Catonsville campus, where they built a 2-foot dam to help stop erosion and took water and soil samples of area streams.

SPEYSIDE, Tobago - An insistent rain is penetrating the thick canopy of the steamy tropical rain forest, but it offers little relief to hikers along the rugged muddy path of the Gilpin Trace. William Trim pulls an orange poncho over his head to protect his binoculars and gear, despite the enveloping humidity. "This rain may help someone, for we can surely use it," says the man who supervises Tobago's national parks. Drought has parched the Caribbean nation of Trinidad and Tobago as it waits for the imminent advent of the rainy season.

ORGAN PIPE CACTUS NATIONAL MONUMENT, Ariz. - Until recently, this vast park 130 miles west of Tucson and cheek-to-cheek with Mexico was known for its 26 varieties of cactus and stunning high-desert views. But during the past year, Organ Pipe has become a place where someone toting a backpack or driving a camper might be involved in something more than sightseeing. Park officials estimate that illegal users of the back country outnumber legitimate overnight hikers and campers 10 to 1. So far this year, there have been 25 major drug and alien smuggling incidents.

GLOUCESTER POINT, Va. - Scientists at the Virginia Institute of Marine Science will soon launch a three-year project to develop a model for multi-species management of sustainable fisheries within the Chesapeake Bay. Bay fisheries traditionally have been managed on a species-by-species basis, with management plans that do not take into account factors such as the abundance of competitors, predators and forage species. With a $629,000 grant from the Virginia Environmental Endowment, scientists at the Virginia Institute of Marine Science will try a new approach that will consider the entire ecosystem and be based on the development of a food web model for the lower Chesapeake Bay. Scientists know that populations of commercially important fish are greatly affected by the abundance of their prey, their predators and their competitors.

Seeds buried in the mud of Chesapeake rivers for as long as 2,000 years show that human beings, not forces of nature, are to blame for the destructive disappearance of the bay's lush underwater grasses. That's the conclusion of a new study by two Johns Hopkins University scientists who dug deep into 12 bay rivers and creeks, bringing up long cylinders of sediment deposited on the bottom over the past two millennia. Buried in the sediment are pollen, seeds and other clues that tell experts when and how some major changes took place in the bay's environment.

CHARLOTTESVILLE, Va. -- Bob Swap is a big athletic-looking guy. As a walk-on football player for the University of Virginia Cavaliers, he went to the Peach Bowl in 1984. An offensive guard and center, he learned the value of teamwork for achieving success. Today, Swap is a team-building environmental scientist with a Ph.D. from the University of Virginia. Recently NASA appointed him as the U.S. coordinator for the Southern Africa Regional Science Initiative 2000, an extensive international effort to study the atmosphere over southern Africa.

REDMOND, Wash. - Over lunch at his home near Seattle, former Chesapeake scientist Donald Heinle recalls one of the clearest views anyone ever had of the bay. It was windless, late fall or early winter 1963, and Heinle was an observer aboard a military transport that had just scrubbed its mission of dropping paratroopers at Virginia's Fort A. P. Hill. The pilot wanted some flight hours under his belt anyhow, so he flew up and down the length of the Chesapeake. He opened the plane's huge rear cargo door, and for four hours Heinle, a doctoral candidate at the University of Maryland, had an unparalleled view of the 2,500-square-mile estuary passing beneath him. He was not just seeing the bay that day. He was seeing the bottom of the bay - nearly all of it, everywhere but the narrow ship channel, ancient gorge of the Susquehanna River.