Paul Gray, sci­ence coor­di­na­tor for Audubon of Flori­da, exam­ines the health of Lake Okee­chobee and its marsh grass­es — Pho­to by Pur­bi­ta Saha

Okee­chobee expert helps humans and birds find com­mon ground

By Pur­bi­ta Saha

Every piece of Flori­da has its token species. In the south­west, Big Cypress Nation­al Pre­serve has the pan­ther. Ever­glades Nation­al Park, unfor­tu­nate­ly, has the Burmese python. To the north, Lake Okee­chobee has the scarce and dap­pled snail kite.

The notion of a token species is both advan­ta­geous and unfa­vor­able for con­ser­va­tion­ists, said Paul Gray, the Lake Okee­chobee sci­ence coor­di­na­tor for Audubon of Flori­da. Since there are numer­ous species that inhab­it the Ever­glades, it can be ben­e­fi­cial to sin­gle out an organ­ism and use it to define the strug­gles of the ecosys­tem. On the oth­er hand, con­cen­trat­ing on one plant or ani­mal encour­ages peo­ple to look for over-sim­pli­fied solutions.

Accord­ing to Gray, who has spent much of his career on Lake Okee­chobee, the Ever­glades snail kite defies sim­ple solu­tions. Gray’s suc­cess or fail­ure with the now-endan­gered species shows how dif­fi­cult it is to repair an intri­cate and com­pli­cat­ed system.

Dur­ing the past decade, the snail kite has gone from being abun­dant to rare. In 1998, the lake housed 3,400 indi­vid­u­als. But by 2011, the pop­u­la­tion was down to just 700. And the baf­fling thing is, 2011 was actu­al­ly a good year for the birds.

Accord­ing to Gray, the kites were able to raise 200 chicks last sum­mer. Yet this pop­u­la­tion boom was not because of effec­tive man­age­ment by humans. It was due to an increase in exot­ic apple snails, which are out-repro­duc­ing and out-eat­ing their native counterparts.

The snail kite is a bird of prey, a rap­tor, that is unique to South Flori­da, South Amer­i­ca and the Caribbean. Its wingspan aver­ages to 43 inch­es, mak­ing it small­er than a hawk or an osprey, but larg­er than a fal­con. Adult males are dark gray, while females and juve­niles are brown with flecks of white.

The kite’s diet con­sists chiefly of apple snails. In fact, the depen­den­cy is so strong that the bird has evolved to have a slen­der, con­toured beak that allows it to slip between the snails’ shells and pry them apart. Because of this spe­cial­iza­tion, the Okee­chobee kites rely heav­i­ly on the lake. It pro­vides them with ample for­ag­ing sites and nest­ing spots, as long as the water lev­els remain bal­anced through­out the oppos­ing seasons.

Exot­ic snails are dou­ble the size of native snails; their girth is com­pa­ra­ble to that of a golf ball. Gray said that mul­ti­ple preda­tors, includ­ing alli­ga­tors and bass, may be keep­ing the species in check. But the full extent of the snails’ impact is still unknown. “Basi­cal­ly, we’re stumped,” said Gray.

The new­er exot­ic ver­sion of the apple snail (left) engulfs the native species with its size and thick­ness — Pho­to by Paul Gray

The inva­sive snails also have a tougher exte­ri­or than the natives, which makes it more dif­fi­cult for the kites to bore into them. To com­pen­sate, the rap­tors have been select­ing small snails that are easy to break apart. They have mod­i­fied their diets so that they can cohab­i­tate with their new prey items. Still, Gray said that he does not want to pin the future of the kites on these exotics, even though the two groups have lived along­side each oth­er for the past sev­en years.

The snail kite is essen­tial to Okee­chobee in that it indi­cates how healthy the lake is. “If kites aren’t doing fine, the wet­lands aren’t func­tion­ing right,” said Gray.

Gray has made it his mis­sion to bring the kite pop­u­la­tions back to their pre­vi­ous stature. While orig­i­nal­ly from Mis­souri, he has spent the past 24 years on Lake Okee­chobee. He is the only sci­en­tist from Audubon, or any oth­er envi­ron­men­tal group, who is ful­ly ded­i­cat­ed to the lake and its water­shed. “I’m very much a lone ranger,” he said.

While work­ing toward his doc­tor­ate at the Uni­ver­si­ty of Flori­da, Gray stud­ied the mot­tled duck, a species that is endem­ic to the Okee­chobee area. After fin­ish­ing his dis­ser­ta­tion he joined the short-staffed Flori­da Game and Fresh Water Fish Com­mis­sion. He left the job three years lat­er because he felt it focused too much on hunt­ing and recre­ation, rather than conservation.

Gray was then hired by Audubon of Flori­da to man­age the Kissim­mee Prairie Sanc­tu­ary and col­lab­o­rate with the Nature Con­ser­van­cy in buy­ing 45,000 acres of grass­land from pri­vate own­ers. This, he said, was a reward­ing expe­ri­ence, for he was able to restore the hydrol­o­gy of the wet­lands and fos­ter diver­si­ty in the system.

“My job is to get humans out of the way,” said Gray. His dai­ly tasks include iden­ti­fy­ing sources for Okee­chobee’s eco­log­i­cal prob­lems, find­ing out why they exist and pitch­ing alter­na­tives to those most involved in the life of the lake. He does not act as an obstruc­tion­ist; he acts as a mechan­ic. But now and then, Gray becomes frus­trat­ed by the lim­i­ta­tions of soci­ety. He said that peo­ple fall into a repet­i­tive process of mis­man­ag­ing resources, most­ly because they tend to be short-sight­ed. “We think we’re smart but we’re dumb as indi­vid­u­als and as a pop­u­la­tion,” said Gray.

Audubon is flex­i­ble when deal­ing with pol­i­cy­mak­ers and big busi­ness­es. This has caused the orga­ni­za­tion to be labeled as a non-prof­it sell-out. But despite the name call­ing, Gray believes in coop­er­at­ing with oth­er envi­ron­men­tal teams to cre­ate a con­sen­sus and a mes­sage. He said that in the past, umbrel­la groups like the Ever­glades Coali­tion have suc­ceed­ed in get­ting the $13 bil­lion Ever­glades restora­tion plan to also focus on Lake Okee­chobee. He hopes that these advo­cates will once again put forth a stri­dent effort to res­cue the snail kite from its per­ilous situation.

There are oth­er birds on Okee­chobee, besides kites, which Gray aspires to sal­vage. He is cur­rent­ly work­ing on an Audubon project that involves the grasshop­per spar­row. The species is threat­ened because it has lost 90 per­cent of its prairie home. In one part of the swamp, the spar­row pop­u­la­tion has dipped to just 10 indi­vid­u­als. If cli­mate change caus­es sea lev­els to rise as far north as the lake, as long-term pro­jec­tions sug­gest, marsh birds like the grasshop­per spar­row and the Cape Sable sea­side spar­row may not be able to fol­low the retreat­ing fresh water. Hence, the future of these native species depends on their abil­i­ty to be elas­tic in har­row­ing sit­u­a­tions, said Gray.

A female snail kite perch­es on a nest­ing site at Lake Okee­chobee — Pho­to by Paul Gray

Migra­to­ry birds from South Amer­i­ca and the Arc­tic also take shel­ter on Okee­chobee every year. They need to refu­el at the lake before con­tin­u­ing on their long and ardu­ous jour­neys. But with reced­ing habi­tats and dimin­ish­ing fish and inver­te­brate pop­u­la­tions, these nomadic birds are being seen less often with­in the vicin­i­ty of South Florida.

At age 55, Gray’s endurance is still strong. He says he intends to work on the lake for anoth­er 10 years, before branch­ing out and apply­ing his influ­ence to state-wide issues.

While suc­cess­es do come, they are hard to see on a day-to-day basis. In fact, Gray said that most days he does not feel like he is mak­ing a dif­fer­ence. “It’s a marathon, not a sprint,” he said.

Progress occurs over mul­ti­ple gen­er­a­tions. Just as Gray looks to the tri­umph of the Kissim­mee Riv­er project for inspi­ra­tion, he fore­sees that future con­ser­va­tion­ists will look to Okee­chobee and its kites to light their own ambitions.