Rising seas threaten Florida’s historical sites. This archaeologist wants to fight back.

This article is part of a Paste BN Network reporting project called “Perilous Course,” a collaborative examination of how people up and down the East Coast are grappling with the climate crisis. Journalists from more than 35 newsrooms from New Hampshire to Florida are speaking with regular people about real-life impacts, digging into the science and investigating government response, or lack of it.

The grassy hill, crawling with snake plants and sabal palms, towered over Sara Ayers-Rigsby as she observed the erosion at its base.

The archaeologist gingerly arranged a photomacrographic scale on top of the tightly packed oyster shells exposed at the foot of the hill, as if the weight of the pocket-sized paper measuring tool may leave a mark.

She recorded any changes, however small, with pictures on her phone and scribbles in her notebook.

This shell mound in Jupiter, Florida, was built thousands of years ago by the Jeaga, a Native American people who lived in northern Palm Beach and coastal Martin counties. The mound had outlasted time, construction and mining of the material for roads.

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Early South Florida pioneers Henry and Susan DuBois built a home on top of the mound near the turn of the 20th century, and today the historic residence watches over an 18-acre county park visited by snorkelers and beach walkers, with picnic tables placed strategically under the shade of sea grapes that offer shelter on a hot day. 

The site’s existence reinforces the notion that this spot was well enjoyed by humans over the centuries, and therefore made a priority to maintain it as a cultural resource. Yet the vast story of how humans lived, revealed by historical and archaeological sites across Florida, is increasingly at risk of being lost forever to the tides because of the manmade climate crisis.

Some cultural sites like DuBois Park are well known and public, while the locations of others are familiar only to archaeologists. These places, important for research, are kept under wraps by state law to prevent looting.

Some sites face swifter or more drastic impact than others. 

The exposed shell on the mound in Jupiter, for instance, may face quicker deterioration with heavier or more frequent storms, said Ayers-Rigsby, a director with the Florida Public Archaeology Network, a statewide education organization of the University of West Florida. She oversees the southeast and southwest region, hosted by Florida Atlantic U

As she walked around the site, she pointed to other climate crisis effects, like how the county government was in the process of moving another DuBois family structure because it faced sea-level rise.

Connecting to ‘this larger timeline’ 

“It’s not exciting or important if you’re doing archaeology just for the sake of doing archaeology,” she said. “It’s exciting and important because it has relevance to people that are living now.” 

With hundreds, if not thousands, of cultural resources across the state, where does an archaeologist even begin to take action? First, it’s ensuring that South Florida counties — which banded together to develop an action plan on how to collectively address climate change — also recognize the impact on archaeological resources.  

Ayers-Rigsby teamed up with fellow archaeologists to list cultural sites that local governments could refer to when prioritizing post-storm damage inspections or addressing preservation when appropriate, first in Palm Beach County on Florida’s east coast, then on the west coast in Collier County.

Ayers-Rigsby is continuing this project in Miami-Dade County, where she envisions that a site called Miami Circle, a national historic landmark, will be prioritized.

Before Spandex-clad joggers trotted along the riverfront, before the sound of morning traffic echoed off high-rises, before cruise ships laid in wait for tourists, the Tequesta, a Native American tribe that lived along the southeastern coast of Florida, settled on this land where the Miami River meets Biscayne Bay. The site was set for redevelopment in the 1990s, but the discovery of limestone circles led to an extraordinary effort to preserve and display this history.

Today it’s a rare splash of public green space in downtown Miami, two acres in all, enjoyed on a recent morning by dogs frolicking off-leash and a longboarder land-paddling up and down the paved path. 

“This is the history of who we are as people," Ayers-Rigsby said at the site. "We’re looking at the history of people occupying the Miami River for thousands of years, so we don’t want to lose our sense of heritage and our sense of the past with modern climate change, right? Because then we’re disconnected (from) this larger timeline."

‘Breaking the family curse’ 

Ayers-Rigsby grew up knowing she wanted to be an archaeologist. She credits frequent trips to the museum as a child and reading Cynthia Voigt novels, as well as family members who shared a love for the subject but never worked in the field.  

When her parents lived in Germany, her mother took evening classes in Egyptology at the university.  

“She knew it maybe wasn’t for her when they spent, like, an entire semester just analyzing one hieroglyph, and she was like, ‘Wow, this is maybe too detail-oriented for me to fully appreciate,’” she said. Her grandfather, too, enjoyed archaeology. But both ended up working in the world of finance.  

“I feel like I’m breaking the family curse by being an archaeologist,” she said.   

Still, if you find the mother-daughter duo at the museum or at a historical site, they’ll be the ones combing over every didactic panel and soaking it all in.

“We ask a lot of questions of the docent or whoever the poor volunteer is that's taking us around,” she said. “We're definitely those people on a tour group that are like slowing the rest of the group down.”  

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Ayers-Rigsby studied classical archaeology at Trinity College in Dublin, where she learned about ancient Mediterranean artifacts in Greece and Italy, followed by graduate school at the University of Bristol in England, where she expanded on her passion for science communication.

“It was perhaps just the cumulative impact of talking to different people again and again, whether it was on a flight or at the pub or anywhere, I’m always talking about archaeology … and having that experience of chatting with people a little bit about what archaeology is and how it is relevant to modern society,” she said.

Initially, in her career, she didn’t make the connection between her profession and climate change.

Then she moved to Florida. The streets and parking lot outside the Fort Lauderdale office from where she worked often flooded and forced climate crisis issues front and center.

“We often think about it destroying our future, but we don’t talk about how it’s destroying our past as well,” Ayers-Rigsby said. 

For inspiration, she looks to how humans in the past dealt with climate change.

There is evidence that humans began living in Florida as early as almost 15,000 years ago. The Florida of back then was vastly different than today, with the land being twice the width, with a cooler climate and grassy savanna landscape.

Over thousands of years, as Florida’s climate shifted closer to how it is today, people learned to manage their resources properly and deal with shifting environments in their lifetime through natural climate change, compared to manmade changes that intensify and accelerate these conditions.

“There’s a real message of resiliency in the past,” Ayers-Rigsby said. “Archaeology and historical sites have really valuable information for us now as we try to navigate through modern climate change.”

'We’re nothing without our cultural heritage’ 

Whether it's the country’s smallest post office in Everglades City, a shellwork site on Fakahatchee Key, or the nearly 100-year-old Macedonia Missionary Baptist Church in Naples, a cultural resource has a better chance of getting the resources to be saved from climate change if the public is aware of it, as opposed to a secret historical treasure, as tough as it is for an archaeologist to admit, Ayers-Rigsby said.  

She learned that while working with fellow FPAN archaeologist Rachael Kangas in Collier County to coordinate with communities to figure out what cultural resources matter to them.

On Florida’s west coast, Ayers-Rigsby and Kangas invited community input to determine what resources should be saved.

Key to this analysis was a sea level-rise mapping tool developed in part with Michael Savarese, a professor at Florida Gulf Coast University, using settlement money from the Deepwater Horizon oil spill. Those involved ranged from the Seminole Tribe of Florida, museums in the county, the Coalition of Immokalee Workers, local governments and the NAACP of Collier County, the latter of which helped archaeologists identify and prioritize a church that served a historically Black community. This church was not on any historical registry lists.

Stakeholders settled on 10 archaeological sites to serve as samples of vulnerable resources, using a scoring system that considered exposure, sensitivity, adaptive capacity and consequences of inaction.

There may be too many sites to save, or not all sites — known or unknown — can be saved from sea-level rise because of the cost or their location.

“It’s fairly common for cultural resources to escape notice, which is unfortunate. Obviously, we’re nothing without our cultural heritage,” Savarese said. But cultural resources could be a “Goldilocks compromise” between saving natural resources or hard infrastructure like roads and water systems. This kind of assessment also gives local governments a jumping-off point to consider archaeological sites when thinking about responding to climate change.  

A tree can be replanted. A road can be rebuilt. But there’s no replacing a 2,000-year-old shell mound or a Spanish shipwreck from the 1700s, Kangas said.

Preserving a site could mean fortifying a sensitive shoreline with wake-reducing mangroves or building a less ideal and more expensive sea wall. Or, with the case of Calusa Island on Florida’s west coast, there, unfortunately, may be no solutions to combat the rapid pace of erosion to the shoreline, so instead a 3D scan of the site at its most pristine will help it live on digitally.

Fighting apathy, understanding reality 

Much of the discussion surrounding climate change is usually about one of two things: how to slow or eliminate the worsening effects, or how to best prepare for what seems like the inevitable. And with good reason. Scientists reported there was more carbon dioxide in the atmosphere in May 2022 than ever before.  

The thought of climate change clawing its way through time could put anyone in an apathetic tailspin.

Ayers-Rigsby’s sunny disposition and desire to share archaeological knowledge with anyone who will listen powers through any sense of hopelessness.  

“I really like to focus on things that are going well and where we are able to achieve change because I think that shows that it’s possible,” Ayers-Rigsby said. “I think the danger is when you get in a situation where you’re like, ‘Everything is terrible and no one cares or listens to me, so what’s the point?’” 

Not everything can be saved, but what is salvageable should have meaning to those living today.

Back in Jupiter, the reality of archaeology is in plain view, as the presence of artifacts and evidence of past humans won’t stop destructive forces, whether they be climate change or development.

Ayers-Rigsby stood on the shell path on a piece of land that slightly jutted out into the waterway like an outstretched index finger. Palm trees stretched overhead as riprap protected the shoreline from erosion.

From this vantage point, just steps away from DuBois Park and the Jeaga mound, prioritizing historical sites was in a way already playing out.

She pointed to two other archaeological sites within viewing distance.

On the south side is a plot of land under construction, which was a former mobile home park; to the north is the Jupiter Inlet Lighthouse, sitting on top of a sand dune at the water’s edge, which has the investment from the federal government to protect what it can from eroding forces of planetary warming.

Hannah Morse covers consumer issues for The Palm Beach Post. Drop a line at hmorse@pbpost.com, call (561-820-4833 or follow her on Twitter @mannahhorse.