Rising seas could be death knell to sportfish

With global warming expected to trigger a 15-inch rise in sea level by the end of the century, will Southwest Florida’s famed Ten Thousand Islands turn into A Few Hundred Islands?

Not quite.

But a new report predicts that saltwater and freshwater marshes will disappear and, with them, snook, tarpon and redfish and the anglers who chase them.

“That’s one of the most popular fishing areas in the state,” said Patty Glick, senior climate change specialist with the National Wildlife Federation and one of the report’s authors.

In 2005, saltwater recreational fishing generated nearly $413 million in retail sales in Collier and Monroe counties, according to the report.

Armed with computer models, the National Wildlife Federation and its Florida chapter tried to guess what would happen to coastal habitats if the sea rises 15 inches by 2100. That estimate comes from a 2001 report issued by the United Nations’ Intergovernmental Panel on Climate Change.

The authors spotlighted nine sites in Florida that are popular fishing spots, including Ten Thousand Islands, Tampa Bay, Biscayne Bay and Charlotte Harbor.

A 15-inch rise in sea level wouldn’t submerge many of the 10,000 or so islands between Marco Island and Chokoloskee, Glick said. That didn’t happen until a consultant ran a model with 26 inches of water, representing the Intergovernmental Panel’s worst-case guess.

As saltwater creeps farther inland, mangroves will follow, leading to a 16 percent gain. In turn, freshwater marshes will decline by 44 percent and a striking 80 percent of the dry land will become wet.

At a current pace of 2 millimeters a year, sea level rise is rather undetectable, even to longtime anglers. But Pat Kelly, who has spent nearly 40 of his 57 years fishing around the Everglades, swears that the rise “is going to happen.”

When the salt marshes flood, young fish and crabs will lose their home, Kelly said.

Global warming will lead to more prevalent red tide blooms, the fish-killing, cough-inducing algae that has menaced Southwest Florida’s beaches in recent years, Glick wrote.

Furthermore, coastal residents can expect the intensity of hurricanes to go up as ocean temperatures increase. The number of Category 4 and 5 hurricanes in the Atlantic, Pacific and Indian oceans has almost doubled over the past 30 years, according to the report, citing recent studies.

Such claims aren’t universally accepted among scientists. In the case of hurricanes, many climatologists attribute the uptick in hurricane activity to natural weather cycles.

The National Wildlife Federation’s report is dotted with disclaimers. One acknowledges that the spread of mangroves is overstated because Marco Island likely will construct sea walls and widen beaches before that happens.

Of all places, most of Chokoloskee will remain high and dry because it was built on a Calusa Indian mound. Across the causeway, low-lying Everglades City will be overrun with mangroves unless officials raise barriers against the sea.

Tom Smith, research ecologist with U.S. Geological Survey in St. Petersburg, said the Everglades restoration effort might help push the encroaching saltwater back out to sea as officials get the River of Grass flowing again.

But that could lead to a problem.

“Are you going to squeeze mangroves on both sides?” Smith asked.

In the struggle against sea level rise, hurricanes could prove an ally, Smith explained. Hurricane Wilma piled up about 4 inches of sediment along creeks near the tip of Florida, resulting in 50 years of protection from rising seas.

Glick’s report, titled “An Unfavorable Tide,” is aimed at galvanizing the National Wildlife Federation’s base of recreational anglers, she said. With a new governor set to take office next year, Glick hopes political will turns in favor of combating an unruly sea.

“If people love this state as much as we think they do, getting this information is going to be a wake-up call,” Glick said.