Oldest Known Roseate Spoonbill Identified Thanks to Lucky Photograph


Last week, biologist Jerry Lorenz squinted at his computer screen. As he scrutinized a photograph of a tarnished metal band wrapped around a spindly bird leg, he thought he knew what he was looking at—but he almost couldn’t believe it. He called one of his biologists in and pointed at a series of blurry numbers and letters. “What do you see here,” he asked. “I’m not going to give any hints.”

The band belonged to a Roseate Spoonbill, a spectacularly pink tropical wading bird that lives in Florida’s Everglades. The band was also an old one, part of a batch of nearly 2,500 that Lorenz and his scientific team attached to spoonbill chicks between 2003 and 2005. The employee looked at it for a few seconds and said: “I see a seven and an eight.”

Lorenz, Audubon Florida’s science director based at Everglades Science Center in the Keys, needed one more check of his eyesight. So, he called in another team member and asked the same question. The second biologist gave him the same answer: a seven and an eight. As they squinted at the screen together, Lorenz talked through the possibilities: Are you sure it’s an eight? Might it be a three, or a B, or possibly a six? But the scientist insisted.

Lorenz was vindicated. He opened a spreadsheet that listed where each of those 2,500 chicks were banded. “I knew right away it was one of the first bands we put out,” he says, based on the digits alone. He scanned through the data to bird number 78: It was banded in December 2003 at Frank Key, a small mangrove island in Everglades National Park. That made the spoonbill 18 years old—the oldest Roseate Spoonbill ever recorded throughout its entire range, from Argentina to Florida. The previous record was 17, also recorded by Lorenz.

There’s little else known about this bird. Lorenz can’t confirm its sex, or how many chicks it’s raised in its 18-year lifetime. What impressed him most, he relayed to me over the phone amid his immediate excitement about the discovery, is that the bird is still nesting in Florida Bay and Everglades National Park after all this time. The photograph of the band, taken by conservation photographer Mac Stone, was captured on Black Betsy Keys, just five miles away from the bird’s natal island.

“What this tells us is that these birds really want to nest out there,” Lorenz says. Spoonbills have been declining in the area over the decades. “We’re losing our birds here in Florida Bay for a variety of reasons,” he says. During its lifetime, this spoonbill has seen five inches of sea level rise in the Everglades. That saltwater has infiltrated its foraging grounds, making freshwater shallows unsuitable for the small fish it eats, Lorenz says. As a result, many spoonbills are leaving the Everglades—or trying to nest there and failing.

The changes the bird has seen aren’t all bad. “It’s also seeing some improvement in the health and productivity in the Everglades,” Lorenz adds, as major projects to restore the highly altered swampland progress. Those projects aim to draw freshwater into the system from the north, even as saltwater infiltrates it from the south.

The photographic evidence was taken as part of a scientific project Lorenz is heading up with Stone, who worked for Lorenz as a spoonbill biologist 10 years ago. The pair, with the help of other field staff, are testing whether remote-capture cameras set up to observe nests can glean new information about spoonbill biology while relieving researchers of the hard labor—boating and hiking out to remote mangrove keys—required to track spoonbill nesting success.

The cameras would also ensure that biologists disturb the nesting birds as little as possible. Human presence on the islands, even for a few hours a month to observe the nests, can potentially stress out the parents and their young or attract predators. “You want to have minimal disturbance—that’s the goal. At the same time you want to have this data,” Stone says. “What is the best way to have our cake and eat it too? We think the cameras are the key to that.”

The team is experimenting with different camera setups, all of which automatically capture photographs throughout the day to record whether eggs or chicks are surviving. Most of the 40 cameras currently in the field are palm-size plastic boxes clamped to a mangrove branch with the lens fixed on a nest; at the end of the season, Lorenz can download the images to view glimpses of the nest’s full story. 

On April 2, though, Stone wanted to capture higher-quality images of the birds living their intimate moments. So he brought out the big guns: his personal camera, a Canon 5D Mark III DSLR with a 24-105mm f/4L lens. At 9:30 a.m. he set the camera to take three photographs—each at a different exposure—every minute. By the time the camera battery died at 4 p.m., it had captured 1,176 photos of the birds.

Stone downloaded the images onto his computer and pored over them. One parent stayed with the chicks most of the day. But at around 2:30 p.m., the other parent returned to the nest. When Stone looked closely at the photo, he noticed a metal band wrapped around its leg—a happy surprise. When he selected this nest to photograph, he didn’t know the bird was banded. “It was pure luck,” Stone says.

He combed through the images. In most, the band numbers were not readable—a problem with the bands that has tortured the spoonbill scientists over the years. Within five years of banding those roughly 2,500 chicks in the early 2000s, the bands began deteriorating. First the paint flaked off. Then the aluminum began oxidizing into nothing. Today most of the remaining bands are practically unreadable. Out of about 20 reports per year, Lorenz can interpret maybe one or two of the alphanumeric codes, he says.

Familiar with the bands’ issues from his years of working for Lorenz, Stone was persistent. He looked through hundreds of photos until he found one where the bird was positioned just right, and the light was angled in exactly the right way, that he could read the band. He called Lorenz. “I’m pretty sure this is a seven over an eight,” he relayed.

That’s when Lorenz invited the parade of biologists into his office to confirm the interpretation. Soon, Stone got a phone call from Lorenz. “This is the oldest-known spoonbill ever found in the wild,” Stone recalls Lorenz telling him.

“I said: ‘No way, are you serious?’” Stone says. “The chance to get this is so slim. And then finding it like a Christmas present when the photos come up on the computer—it’s one of the great pleasures of doing this work.”

The discovery of the oldest spoonbill is exciting, but it’s not the only information Lorenz has gleaned from his banding project. Even as the bands deteriorated, making him unable to follow individual birds, he was able to generally track the movements of birds banded in Florida Bay (wearing black bands) versus those banded in Tampa Bay (wearing red bands). At the time, he had hypothesized that the birds move freely between the two nesting sites. But the band data showed that Florida Bay birds prefer to stay in Florida Bay, and that Tampa Bay birds prefer to nest in Tampa Bay.

In that way, spoonbills are homebodies who like to stay in the familiar places where they grew up. “You come up with the hypothesis and the birds tell you you’re dead wrong,” Lorenz says. “That is when scientists get the most excited. The knowledge armed me with new ideas about why the Florida Bay birds are doing so poorly while the Tampa Bay birds are doing so well.” Specifically, the Florida Bay birds rely on Everglades health, which has been degraded by a century of human development and also by more recent sea level rise.

The new photograph and record of the 18-year-old spoonbill follows that trend. This bird could have up and left for more productive foraging grounds farther north in Florida years ago. But instead, it keeps trying to nest within miles of the place it was born in Everglades National Park.

“Despite all these challenges the Everglades are throwing at them, they are desperately trying to make it work here,” Stone says. “They keep coming back. They want to live here. They want to raise their young here. I think that’s a really cool story.”



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