As rich as it is in eye candy with its sparkling, shell-strewn beaches, its lush, technicolor landscape and its amazingly starry nights, Sanibel Island is also a haven for the sounds of nature. A self-proclaimed sanctuary island, Sanibel is nearly 70 percent preserved, undeveloped land. That makes it a mecca for birds—migratory, seasonal and year-round.

The barrier island has a troupe of lead vocalists that may be considered its iconic bird sounds. Relatively quiet wading birds such as herons, egrets, ibis and the coveted roseate spoonbill are often linked most closely to Sanibel’s beauty and charm. But, when serious birders and researchers are asked which sounds they most readily identify with the island, they mention a wide-ranging cast of raptors to songbirds, as well as nocturnal species.

When considering the No. 1 sound that conjures images of Sanibel, it makes sense that the osprey comes to mind. With a loud, confident voice and a high perch, the brown-and-white striped raptor is also known as the fish hawk. It’s found in coastal areas everywhere except Antarctica and is especially prolific on Sanibel. 

“We have one of the highest densities of osprey as anywhere in the U.S.,” explains Jim Griffith, president of the Sanibel-based International Osprey Foundation, or TIOF. “For the last two to three years, we’ve counted as many as 450 to 470 ospreys on the island.”

In the early ’70s, there were only about 24 nests and now there are about 100 productive ones, according to TIOF. “The osprey has really made a comeback since DDT was banned in the ’70s and we sure see it here,” adds Griffith, who has a signature design for osprey nesting platforms and has built more than 200 for placement in Southwest Florida. 

Having resided on Sanibel for more than 20 years, near Blind Pass, he’s seen and heard many a battle between the much less vocal bald eagle trying to steal the osprey’s catch of the day. “The osprey is much better at fishing. It’s built for it. The eagle isn’t,” Griffith says.

“But, the eagle is much bigger and nearly always wins,” he continues. “The osprey will call out during battle but the eagle doesn’t. The osprey is the most magnificent bird on the island. And, it’s very active with its calls.”

TIOF founder Mark “Bird” Westall left a legacy after his death in 2017, as he was known to communicate with the resident osprey. He believed they recognized his voice as well. Griffith notes, “ ‘Bird’ was a master of the osprey language. He identified at least six distinct calls that he recognized over the years.” 

Griffith, who enjoys jogging before sunrise, finds daybreak to be one of the most magical times to deeply tune into the avian overture. “The northern cardinals are something to marvel at—every morning they are singing some beautiful songs,” says Griffith, who is also president of the Sanibel-Captiva Audubon Society. 

Research as well as the refined ears of birders tells us that the strong whistle of the cardinal, followed by its staccato trill, is unique to each bird. As are the gentle coos of the mourning dove that also greet the warming morning sun on the island.

“Just as we individuate other humans by how we distinguish their faces, birds distinguish between each other by their calls and songs,” says Ken Meyer, executive director of the Avian Research and Conservation Institute, or ARCI, in Gainesville, Florida. “Every bird has its own individual sound.”

To notice the subtle differences between each bird requires deep listening and rapt attention. And, years of attention. 

“If you watch a bird singing, you can see their mouth open and their chest pounding,” adds Meyer. “It sounds relaxed and casual to us, but to the bird it takes a lot of energy to throw that sound out. … They don’t waste their precious energy. Every song or call provides very specific information.”

Don and Lillian Stokes have published more than 35 books, including seminal field guides to North American birds. They’ve been seasonal residents of Sanibel for more than 20 years and their ears are expertly attuned to their feathered friends.

“Any place on Sanibel is a great place to listen for bird sounds. Birds are everywhere here,” Lillian says. “One of our favorite unique bird sounds on Sanibel is listening to the northern mockingbird at Bailey’s General Store. In early spring, the mockingbird, who mimics the sounds of other birds it hears, will start to sing the song of the gray kingbird as part of its song repertoire, before the gray kingbird has returned from migration. It’s a bit of a mystery how it knows to do that.”

Don Stokes, who first visited Sanibel in 1959, delves even deeper into the art of tuning in as a way of noting the difference between hearing the mockingbird, a year-round resident, and the catbird or thrasher that are seasonal:

“There’s a group of three birds called Mimidae that mimic the songs of other birds. And, it’s a wonderful story because they don’t have their own songs but they’ll pick up any other song and use it. So, the catbird does other songs constantly one after another. A thrasher does every birds’ call twice and the mockingbird does every birds’ call three times in a row,” he says. 

Veteran birders such as Don and Lillian Stokes are very adept at distinguishing unique calls and at knowing such nuance in sounds that signal the seasons, such as the buzzing note of a prairie warbler that’s taking a rest on its spring migration. “Spring migration is not easy birding,” notes Don, adding it occurs between the end of March and early May. “In terms of birding being easy or hard—it’s challenging.”

Tuning into the brief, high-pitched sounds helps birders know where to point their cameras and binoculars. For some, seasonal bird sounds are a very reassuring part of life. “When I hear chuck-will’s-widow—with its call that sounds like its name—it tells me that all is right in the world,” says Phyllis Gresham, vice president of the Sanibel-Captiva Audubon Society. “In early spring, I start to hear it at night and I just love it.”

For a bird that dwells deeply in the island’s dense mangroves, researchers use its guttural “gagagaga” sound to help them tag and study it. “The mangrove cuckoo can be heard when its hormone levels are coming up for reproduction from March, April, May and into June,” explains Meyer. “You might even hear one in early July.” 

Meyer is currently tagging and studying the bird in the J.N. "Ding" Darling National Wildlife Refuge on Sanibel, known as one of the country’s top birding destinations. “We ‘play back’ the vocalization to attract birds to net and tag, but we discourage anyone from using playback as a way to check a bird off their life list.”

With smartphones and digitized bird sounds so readily accessible, birders are tempted to play calls and songs to elicit a response from the mangrove cuckoo and other elusive species. 

“It can really interfere with their natural behavior. It could cause a bird to think there are more of his species or could interrupt nesting,” says Meyer. He notes the study is intended to verify the mangrove cuckoo’s nesting and migratory patterns. 

Changes in bird behavior and sound can signal environmental concerns. A raptor that is heard less often now on Sanibel is the red-shouldered hawk, which numbered only 18 in the Sanibel-Captiva Audubon Society’s 2017 Christmas bird count. In 2005, there were about three times as many.

“We don’t hear that hawk like we used to,” says Charles Sobczak, noted Sanibel author and naturalist. “That’s because of the rat poison that’s been used.”

The Sanibel-Captiva Conservation Foundation started a campaign several years ago to discourage highly toxic rat poisons and to encourage trapping instead to deal with rats, which are prey for owls, eagles and hawks. 

For Sobczak, bird sounds soothe the soul and put his naturalist’s sensibilities at ease. “So many people don’t hear the birds and it’s such a shame,” he says. “Another sound that is iconic on Sanibel is the eastern screech owl. They call out and answer each other at night. You can hear them a mile a way in the still of the night.”

As a great way to be fully present in the moment, you might consider slowing down and listening to Sanibel’s unique symphony of bird sounds. “Some people hear it as noise, but the sound of birds is music to my ears. It’s one of the most beautiful parts of life,” says Griffith.

When you can’t listen to Sanibel birds in person, hear them online! Search by species or visit: ebird.org (eBird—managed by Cornell Lab of Ornithology—“is the world’s largest biodiversity-related citizen science project.”)

The International Osprey Foundation, ospreys.com

The Sanibel-Captiva Audubon Society, san-capaudubon.org

Ding Darling Wildlife Society, dingdarlingsociety.org

Written by Barbara Linstrom, who first wrote for Times of the Islands in 1997 with its premiere issue. Her family discovered Sanibel on vacation from Ohio winters in 1976. She has a master’s in journalism and wrote for wire services and newspapers in Italy, Venezuela and the Caribbean before moving to Sanibel 25 years ago.