MIDDLE TOWNSHIP — Laurie Pettigrew scans the skies above the salt marsh near the Wetlands Institute and spots four bald eagles.

“Good grief, look at that. One adult and three immatures,” said Pettigrew, a biologist with the state Department of Environmental Protection’s Bureau of Land Management.

Large raptors flying overhead are a clear sign that the marsh surrounding the Wetlands Institute is healthy and teeming with food this mid-winter day,

But for how long?

Federal and New Jersey Fish and Wildlife agents have, for the past decade, been racing to buy wetlands and nearby high ground surrounding existing refuges to ensure that rising sea levels won’t turn these wildlife-rich areas into barren islands.

With sea levels rising, today’s upland could be future salt marsh, said Andrew Milliken, a coastal ecologist with the U.S. Fish and Wildlife Service.

Wildlife officials believe that by buying the high ground, they are preserving room for the existing marsh to migrate there, as a result of global warming and the rising sea level that is occurring.

But if that land is privately owned, the likelihood grows that the owner will add a bulkhead, a move that will protect their investment, but one that would turn the marsh into less productive open water.

U.S. Fish and Wildlife has spent $300 million buying properties from willing owners in New Jersey since 1992.

On this day, Pettigrew is scouting for another buying opportunity.  The state and federal governments buy marshland because of its benefits to wildlife, flood control, water quality and recreational pursuits that include hunting, fishing, bird-watching, crabbing and boating.

“Climate change in general, and sea level rise in particular, are more and more being incorporated into our planning. We need to protect upland buffers as a place this marsh could eventually migrate to,” Milliken said.

Lots of life

In the winter, the marsh looks brown and dead, but it’s alive with great blue herons, boat-tailed crackles, wintering sparrows, loons, brant and other species. Many of those birds are still eating fish in large numbers in the back bays during the winter. In the summer, a whole different set of birds arrives, including the endangered black skimmer and the threatened black-crowned night heron.

That’s one of the reasons the state and federal governments have been buying up coastal wetlands for years. Saltwater wetlands are the second-most productive ecosystem on Earth, Pettigrew said.

Pettigrew is scanning wetlands the state has already purchased, part of the 17,273-acre Cape May Wetlands Wildlife Management Area, which is buffered on the western side by stands of timber. She is also scanning that timber line.

The state recently received $2.2 million in grant funds to purchase 140 acres in the Middle Township marshes and the adjoining upland.

The forest land is the next target of state and federal wildlife agencies. Officials don’t want the exact locations known yet, but say they will only buy from willing sellers.

There are a couple of houses toward the Garden State Parkway, some farmland and some upland forested area. The rest is transition from uplands to salt marsh next to Jenkins Sound,” said Eric Shrading, a biologist at the U.S. Fish and Wildlife Service office in Pleasantville.

 Much of the $300 million funding from the National Coastal Wetlands Conservation Grant Program comes from an excise tax on fishing equipment and motorboat fuel. Marsh acquisition funding also comes from state Green Acres money, waterfowl stamps, fish licenses and other such sources.

Rising sea level

Milliken said sea level rise could range from 6 inches to 4 feet by the end of the century based on calculations from the Intergovernmental Panel on Climate Change, or the IPCC.

“It’s a huge range. What that rate is matters a lot. We’re expecting about one meter, which is a lot,” Milliken said.

As the Earth warms, sea levels rise due to melting ice and thermal expansion of sea water. Some coastal areas, including southern New Jersey, will also suffer due to land sinking after the last ice age ended.

“The Mid-Atlantic is an area where there will be a higher level of sea level rise because the coastal area is still subsiding,” Milliken said.

Professor Kenneth Miller, of the Rutgers University Department of Earth and Planetary Sciences, said he expects sea level to rise by 3 feet by the end of the century, but the land will also sink by about 4 inches in this region during that time. Miller said some specific areas, including Atlantic City, will sink more due to groundwater withdrawals.

Climate predictions are an inexact science and Miller added some perspective. He said 50 million years ago there was no ice on Earth and the ocean was 200 feet higher.

As the atmosphere cooled, ice formed and ocean waters shrunk. By 125,000 years ago, Miller said, sea levels were only 15 feet higher than today.

The last ice age, Miller explained, ended 20,000 years ago and the waves broke 70 miles further out than today.

“You could about sit on the beach and fish in the canyons,” Miller said.

Still, Miller agrees with the planning effort.

“With bulkheads, you lose commercial fisheries and recreational uses of the marsh. You can’t have people building right up to the edge of the marsh and not have a place for the marsh to roll to,” Miller said.

Environmental groups also support the effort.

“It’s good. With sea level rise and storm surge, this helps people inland. They know there’s going to be a problem, so you have to set those areas aside now,” said Jeff Tittel, director of the New Jersey Chapter of the Sierra Club.

Contact Richard Degener:

609-463-6711

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