Climate change and endangered islands threaten brown pelicans

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CHAUVIN, La. (AP) — Sliding off the side of her small boat, seabird biologist Bonnie Slaton wades through waist-deep water, brown pelicans hovering above her head, up to until it reaches the shores of Raccoon Island.

During seabird breeding season, the place is a boisterous symphony of noise and movement – ​​and one of the few remaining havens for the iconic pelicans.

The crescent-shaped island is the last strip of land separating Louisiana from the Gulf of Mexico – a natural speed bump against storms that arrive from the sea. An hour by boat from the mainland, the barrier island’s remoteness allows birds to nest on mangroves and sandy beaches at a safe distance from most predators.

A dozen years ago, there were about 15 low islands with nesting colonies of the Louisiana state bird. But today, only about six islands in southeastern Louisiana have brown pelican nests – the others have disappeared underwater.

“Louisiana is rapidly losing land,” said Slaton, a researcher at the University of Louisiana at Lafayette. “Sea level subsidence and rise are a double whammy.”

The endangered islands threaten one of the most famous conservation success stories of the past century – the decades-long effort to bring pelicans back from the brink of extinction.

On land, brown pelicans are clumsy birds, their huge beaks and wings lending them what Slaton calls a “clumsy” look. But hovering low over the ocean, their wings brushing the water, pelicans are streamlined and majestic.

The same forces that are engulfing these coastal islands are also causing southern Louisiana’s saltwater marshes to disappear faster than anywhere else in the country. Scientists estimate that Louisiana loses a football field every 60 to 90 minutes.

“We are on the front lines of climate change. It all happens here,” said Jimmy Nelson, an ecologist at the University of Louisiana at Lafayette.

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Visiting a colony of seabirds is like stepping into the hustle and bustle of a bustling city, with quarters of birds loosely grouped by species – pelicans, terns, egrets, spoonbills and gulls, all carrying meals to chicks.

As Slaton and two other biologists walk along the shore of Raccoon Island, the birds land. The swirling, plunging cacophony of feathered life heralds intruders. The calls of a thousand laughing gulls are loud enough to drown out human thought.

As Slaton treks across the sand dunes to change the batteries and memory cards of 10 trail cameras on poles, his t-shirt becomes speckled with white bird droppings.

Motion-activated cameras are set up to observe pelican nests in a variety of habitats. Some of the circular Smooth Cordgrass nests are built on top of mangrove stands, others on grassy mounds.

Early birds are taking over mangrove penthouses, where nests have a better chance of surviving storms, Slaton says. “Late nests are on the ground, which is more risky.”

Camera data has shown that in recent years the main threat has been flooding – which can wash away entire nests, as happened in April 2021.

Passing a nest on the ground, Slaton bends down to watch two tiny featherless gray and pink pelican chicks squirm with their eyes still closed. She thinks they hatched overnight or earlier in the day.

Within a week, the chicks are covered with fluffy white and gray feathers. When the parents are out of the nest, the older chicks stand guard, swaying and hissing at perceived threats.

Observing a colony of seabirds reveals both the promise and the fragility of new life. Then, suddenly, the biologists again wipe white drops from their foreheads.

They don’t like air assaults. After all, the abundant bird droppings act as a natural fertilizer that helps shrubs and grass grow from the sand and rocks of the island. Their roots slow erosion.

Without seabirds, the earth would disappear much faster.

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When Mike Carloss was a kid in Louisiana in the 1960s, he never saw brown pelicans.

Large coastal birds were among the first species declared endangered in the United States in 1970. Like bald eagles, their populations have been decimated by the widespread use of the pesticide DDT, which thins eggshells and prevents healthy chicks from hatching.

The beloved pelicans had completely disappeared from Louisiana, where their likeness remained only on the state flag. But a long-running effort to bring them back has led to one of the country’s most inspiring comeback stories.

After DDT was banned in the United States in 1972, biologists brought pelican chicks from Florida to repopulate empty islands across the Gulf of Mexico. More than 1,200 have been released in southeast Louisiana over 13 years.

One location was Raccoon Island, where Carloss, then a teenage field assistant with the Louisiana Department of Wildlife and Fisheries, remembers throwing fish from the beach to feed the chicks, as a sort of surrogate parent.

“I kept these young pelicans on a remote island,” he recalls. “Somebody had to hand-feed them basically.”

As state wildlife biologist for more than two decades, Carloss then oversaw several restoration projects on the island. But now he fears that if the islands continue to disappear, “we’ll be back to the 1960s era, and not because of the poisoning”.

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Protecting what remains depends on continued human intervention.

Today, one side of Raccoon Island is surrounded by granite breakwaters that divert the tides. Sand was pumped in to fill small lagoons that are beginning to form.

Erosion is a natural process and over thousands of years most barrier islands rise and fall. Unlike the volcanic islands, there is no bedrock, only layers of silt have flowed into the Mississippi Delta.

Barrier islands, as environmental historian Jack Davis once wrote, “are impermanent and precarious places, at the mercy of wind and washing water – which make them, shape them and destroy”.

But rising seas and increased frequency and intensity of storms linked to climate change are accelerating the pace. And the islands have been deprived of new sediment from the Mississippi because the course of the river has been controlled since the 1940s with levees to prevent flooding and facilitate navigation.

“This prevents sediment from reaching rapidly sinking areas,” said Jaap Nienhuis, who studies erosion at Utrecht University in the Netherlands and previously conducted research in Louisiana. “The Louisiana coast is losing land at perhaps the highest rate in the world.”

Every few years, government agencies undertake work to restore and maintain some of the barrier islands, a never-ending job. The money so far comes from a legal settlement after the 2010 Deepwater Horizon oil spill that killed hundreds of thousands of marine animals.

But that won’t last forever – and many sinking islands aren’t restored at all.

Another day, the biologists steer their aluminum boat past an unrestored island called Philo Brice. Mangroves grow on flooded lowlands and pelicans nest in the upper branches, the chicks tending when the parents land with meals of fish.

It’s still a decent breeding habitat, as long as the soil holds and the plants stay above water. “In five or 10 years, it may or may not be here. It’s that fast,” Slaton said.

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Flying in a small plane 500 feet (152 meters), low enough to see the heads of pelicans sticking out of the mangroves, the difference between Raccoon Island and unrestored Philo Brice is stark: one is solid land, the other like soft bread dissolving in a soup of blue cheese.

When biologist Juita Martinez conducted research on the Louisiana coast between 2018 and 2021, she found that the number of pelicans on another unrestored and flooded island, Felicity, dropped from 500 to around 20.

“Over the past two decades, we’ve lost so many pelican nesting sites,” she said.

Brown pelicans can live for over 20 years, and in long-lived seabirds the impact of reproductive problems takes time to become clear.

For now, pelicans are still common on the Louisiana coast, and their likenesses are everywhere – license plates, mugs, t-shirts, restaurant signs and university seals.

At the Bayou Boogaloo music and arts fair, pelican artwork often sells first, said New Orleans painter Patrick Henry, standing with his brightly colored bird portraits.

The brown pelican “is a symbol of Louisiana, just as the eagle is a symbol of America,” said Rue McNeil, executive director of the Northlake Nature Center in Mandeville, Louisiana. “It was put on the state flag because that particular bird represents a lot of strength.”

And “sacrifice,” she added.

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Disappearing islands aren’t just a problem for birds.

On a recent afternoon, Theresa Dardar called her neighbors as she and her husband Donald lowered their small boat into the Bayou of Pointe-au-Chien in southeast Louisiana.

Everyone knows each other here in the close-knit community of the Pointe-au-Chien Indian tribe. But their world is changing rapidly.

“This bayou, I went down it with my grandfather. I could reach out and pull the grass on the dirt on either side of the boat,” Dardar recalled. “But look how wide the water is now – all that land is gone.”

The boat passes a single white cross on a low shore – marking one of the tribe’s eight burial grounds on the bayou. The community fears that rising seas and storm surges will wash away their ancestors, memories and culture.

Dardar supports island restoration efforts. “I’m glad they’re doing this for pelicans, but they have to do this for humans too,” she said.

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