Experts warn of shrinking shoreline

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Within 100 years homes, marinas and boatyards could be forced back by rising ocean levels

Within 100 years homes, marinas and boatyards could be forced back by rising ocean levels

Charterboat Capt. Dan Kipnis preaches the gospel of global warming with the fervor of a tent-revival evangelist.

“If you go to England, they believe it. If you go to Germany, they

Read the other story in this package: Global warming a concern for sportsmen

believe it. If you go anywhere abroad, they believe it,” he says.

Here in this country, though, we have lagged behind in believing that the earth’s atmosphere is warming, Kipnis says. He believes science shows it is probably due to the insulating effect of greenhouse gas — carbon dioxide released by burning coal, oil and gas.

Kipnis, who used to run the Reward fleet of party fishing boats in Miami, is president of the Miami Beach Rod and Reel Club and a member of the Florida Wildlife Federation. He shared some new information with Florida sportsmen about likely effects of global warming and sea rise on Florida’s best fishing grounds over the next century. Kipnis and Jerry Karnas, a National Wildlife Federation global warming staffer, presented the results of a new study — “An Unfavorable Tide: Global Warming, Coastal Ecosystems and Recreational Fishing” — May 11 to a group of sportsmen and environmentalists at the rod and reel club.

The federation, working with Jonathan Clough, of Warren Pinnacle Consulting, Inc., set out to see what a 15-inch sea rise over the next century would do to coastal habitat around Pensacola, Apalachicola, Tampa Bay, Charlotte Harbor, the Ten Thousand Islands, Florida Bay, Biscayne Bay, the St. Lucie River, and the Indian River Lagoon. Fifteen inches is the middle-road projection of the Intergovernmental Panel on Climate Change’s “Climate Change 2001: Synthesis Report.” Kipnis says many now think that projection is very conservative in light of the accelerated rate at which the polar ice caps are melting.

The study found that nearly 50 percent (9,294 hectares, or 22,956 acres) of critical salt marsh and 84 percent (67,438 hectares) of tidal flats at these sites would be lost. The area of dry land around these fishing grounds is expected to decrease by 14 percent (70,680 hectares), and roughly 30 percent (405 hectares) of ocean beaches and two-thirds (2,380 hectares) of estuarine beaches would disappear.

“This will affect fish and make for a lot of changes,” says Manley Fuller, the Florida Wildlife Federation’s president and a biologist.

Not to mention its impact on humans. This study is primarily about how sea rise will affect fish and wildlife, yet, “Much of this dry land that will be lost is worth tens if not hundreds of billions of dollars,” Kipnis says. “I have a house on the water. It’s only 3 feet off the water.”

Many homes, businesses, marinas and boatyards will be forced back from what is now the water’s edge, and fishing in Florida will be very different in the year 2100 than it is today.

“Massive changes are in store,” Karnas says. “Where my grandfather fished and where I fish are going to be completely different places from where my grandkids fish,” he says.

One hundred years from now there will be a lot more open ocean, fewer flats, barrier islands and beaches, less salt marsh and more mangroves pushing inland, he says. On average, the temperature of the upper 1,000 feet of the world’s oceans has risen about 0.5 degrees F since the 1950s, and that trend is likely to continue, the report says. Coastal waters will keep getting warmer, as well, to the detriment of some coastal fish species.

One could expect new fish habitat to develop inland as the water rises, and this will happen, but scientists doubt the creation of new habitat — which in the natural course of events takes thousands of years — will keep up with the accelerating rate of sea rise, especially since a lot of new habitat will be over roads and parking lots, and around buildings.

In this radically changed scenario, not only will fish habitats change but some fish species will struggle and even disappear from Florida’s coastal waters. Others will thrive. On balance, though, there likely will be a net habitat loss and fish will suffer, the report says. “Some species are going to win big,” Kipnis says. “Some are going to lose big, but the biggest losers are us. We’ve got to learn to deal with this.”

These changes are in addition to habitat that has been lost already to coastal development. Since the 1940s Florida has lost nearly a third of its seagrass beds and more than half its salt marsh, mangroves and other wetland habitat, contributing to significant declines in fish and wildlife, the report says. The report notes, too, that globally the oceans already have risen an average of 6 inches over the last century. The rate of sea rise would more than double over the next 100 years.

Among the report’s more striking projections:

• Along Florida’s gradually sloped shores, a 15-inch sea rise would translate into water advancing inland by as much as 250 feet.

• Ninety-one percent of Florida Bay’s tidal flats, some of the state’s best waters for redfishing, will be inundated by 2025; 99 percent of the flats will be gone by the turn of the century.

• As sea level rises, open-ocean and estuarine water likely will increase by 64 percent and 18 percent, respectively, around the nine fishing areas, and mangroves are expected to increase 36 percent. Brackish marsh is projected to increase more than 40-fold, mostly around Apalachicola, taking over much of the current hardwood swampland.

• Warmer water in Apalachicola Bay due to global warming could decimate crab, shrimp, oyster and flounder before century’s end.

• Along the Gulf Coast and in South Florida, the most vulnerable habitats are salt marshes and tidal flats. Along the East Coast the biggest problems will likely be beach erosion and swamping dry land.

• The projected 50-percent loss of salt marsh would significantly reduce fish nursery habitat.

• Species most likely to be affected by habitat loss are bonefish, flounder, gag grouper, gray snapper, permit pompano, redfish, snook, spotted sea trout and tarpon.

• Higher air and water temperatures are expected to shift the freeze line north, enabling cold-sensitive species such as mangroves and snook to move farther north.

• Coral bleaching due to higher sea-surface temperatures is expected to become more common and severe in the Florida Keys.

• Algal blooms known as “red tides” and associated fish kills are likely to become more frequent and widespread due to warmer waters and eutrophication (low oxygen in the water due to excess nutrients).

The study proposes a number of actions: adopt policies at all levels of government to limit the production of greenhouse gases, reduce reliance on oil for energy, and cooperate internationally on global warming issues; incorporate planning for sea rise into coastal and resource management; protect undeveloped coastline from development, restore natural coastal habitats and abandon the practice of hardening coastline, so as the sea rises it can migrate over undeveloped land suitable for new fish habitat, and adopt an accelerated program of public acquisition of undeveloped coastline.

Kipnis says it’s time to take the blinders off. “Nobody — nobody — will say how serious this really is,” he says.

More information available at the National Wildlife Federation Web site, www.targetglobalwarming.org/florida.