This was a banner year for South Florida's wading birds, some of the most celebrated denizens of the Everglades.

Scientists who conduct an annual survey around the Everglades region counted 77,000 wading birds nests in 2009, the most since the 1940s and 8,000 more than 2002, the most recent banner year.

Nest counts were more than three times higher than last year and 83 percent higher than the average of the past nine years.

Better yet, experts say the higher nest counts are a trend, not a blip. Back in the '80s the count often came in at under 10,000.

That bodes well for the ecosystem as a whole, says Mark Cook, senior environmental scientist for the South Florida Water Management District and one of the authors of the 2009 South Florida Wading Bird Report.

"Wading birds are a top predator. If they are doing well, we know other things are doing well," he said.

Perhaps the biggest winner among the region's wading birds this year was the endangered wood stork, which built some 6,400 nests, 18 times as many as in 2008 and three times as many as they've averaged over the past decade.

The white ibis, a bird so ingrained in the South Florida psyche that the University of Miami has made it its mascot, also was busy this year, building 400 percent more nests than 2008 and twice as many as their average for the decade.

Researchers counted most of the wading bird nests in a series of Water Conservation Areas that extend from west of Miami up to Lake Okeechobee. But 2009 also brought the largest nest count in Everglades National Park since 1941.

Not all of South Florida's wading birds fared well, however. Nest production for the roseate spoonbill was lower than average. But even so, there was good news.

The pink-breasted beauty hatched more than two chicks per nest, the fourth straight year the number has exceeded the one per nest average that scientists use as a measuring stick for a successful season.

Audubon scientist Jerry Lorenz, considered the region's foremost spoonbill expert, expects the higher productivity per nest to payoff for the bird soon.

Experts like Cook and Lorenz say the improving Everglades nesting population is in part due to Mother Nature. Recent summers have been wet, especially in the northern Glades, expanding the range of the small fish that serve as the main protein source for wading birds. Winters, meanwhile, have been dry, forcing minnows and other less bulky fish to retreat into the far smaller areas that remain underwater, where they are easy targets for their avian predators.

Cook said this year's ground-breaking counts may have also been influenced by the 2006-07 drought, which killed off large fish, allowing ground burrowing crayfish to flourish when the water returned. For hungry birds, an abundance of crayfish must have looked like an all-you-can-eat buffet.

Everglades restoration, still in its infancy, hasn't played a part in the recovery, Cook says. But better water management practices have.

Over the past several years water managers have consulted with scientists before releasing water through the extensive system of pumps, levies and canals that has replaced the Everglades natural north-to-south sheet flow.

When they take birds into account, managers can avoid such harmful practices as dumping water into shallow foraging areas.

Earlier this year Lorenz credited more environmentally grounded water management with saving the spoonbill from becoming extirpated in Florida Bay.

Still, he points out, the wading birds of the Everglades are a long way from recovering to the numbers that existed before the canal system was inaugurated in the middle of the last century. In the 1930s annual nest counts sometimes reached 250,000, or even 500,000.

"The years that were good then were upwards of five times what they are this year," Lorenz said.

rsilk@keysnews.com