It comes as no surprise that areas like California experience more wildfires by the year, but even wetland-dense places like Florida are vulnerable to increasingly large and catastrophic fires.
Many Florida ecosystems are actually wildfire dependent. Fire clears out underbrush and prepares soil for germination. However, years of fire suppression have led to excessive growth throughout the state, meaning that fires are more frequent and more damaging than these ecosystems can adapt to. This creates massive clouds of billowing smoke and other environmental hazards when wildfire strikes—often as a direct result of human activity. This risk is compounded by climate-related factors.
In 2025, the wildfire likelihood for Florida was high, with an average likelihood that is greater than that of 86 percent of US states. A recent study from First Street Foundation suggests that the risk of wildfire in Florida could double by 2052.
Plenty of research and resources have been devoted to wildfire risk and vulnerability in Florida. However, little attention has been paid to how these fires affect Florida’s cultural heritage, especially its archaeological sites. Researchers at Lynn University are using a GIS-based approach to address this gap by leveraging ArcGIS to map and analyze the areas in the state that are most vulnerable to wildfire, with the aim of preserving Florida’s archaeological sites—and its history.
From Data to Analysis
To create the wildfire risk map, researchers first obtained archaeological site data from the Florida Master Site File, the state’s official inventory of historical and cultural resources. This data was queried to limit it to artifact scatters, campsites, midden/mound sites (prehistoric landfills and other raised earthworks), and some historical relics such as logging chains. Structures like historical buildings would have a different set of parameters for their preservation during a fire event compared to other archaeological sites. Wildfire data came from Monitoring Trends in Burn Severity (a US federal program designed to map fires across the country), and all data was processed and analyzed in ArcGIS Pro.
To determine the areas at highest risk for large wildfires, a hot spot analysis was completed based on acres burned. Larger fires tend to burn hotter and have the potential for fire to carry along the root structures deeper into the ground. Generally, site damage is correlated with fire duration and intensity. Larger fires could also have indirect effects such as those from suppression efforts and erosion following the fire.
Researchers then compared archaeological site data with the burned areas and further selected for areas with over 23,000 acres burned and over 10 archaeological sites within the boundaries of the wildfire. These were determined as the most vulnerable areas for Florida archaeological sites.
Based on this determination, the risk map combines vulnerability based on hot spot analysis, burn acres, and site density, as well as wildfire susceptibility. Susceptibility is based on the US Department of Agriculture’s wildfire hazard potential data, and archaeological sites were narrowed to those with National Register of Historic Places (NRHP) potential. NRHP eligibility is used to focus on those sites that are deemed to have the most research potential. Sites containing human remains are also considered among the most vulnerable.
The risk map revealed that 380 sites are located in the most wildfire-vulnerable areas. Of these, over 200 are precontact (dating to the period prior to European arrival) and 60 of these are identified as midden/mound sites. Many of the sites are ineligible for NRHP classification, but many more are NRHP eligible or require preservation. Nearly half of the sites do not have enough information for evaluation, meaning damage done to these sites might result in catastrophic loss of data. Most importantly, 22 of these vulnerable sites contain human remains.
Risk and Return
Even with these areas and sites identified, many other factors and unknowns impact how cultural sites are protected from fire damage. The project will be fleshed out over time to include some of these factors, such as proximity to susceptible land cover and site depth.
Studies conducted largely in New Mexico show that fire doesn’t necessarily affect buried cultural materials. Even a few centimeters of soil cover can be sufficient protection. This is good news, as sites in Florida tend to be more deeply buried than those in other states—but it doesn’t mean that Florida sites are not at risk of fire damage. Stumps can smolder and burn, with the potential to affect buried materials in the vicinity. Heavy duff, surface logs, and roots that smolder and burn also have the potential to expose subsurface materials to heat over time. In addition, root structures in many Florida plants are shallow due to high water table, which can carry burn into buried archaeological sites such as midden/mound sites. The southern part of the Florida peninsula also has exposed limestone in many areas, limiting the soil cover.
Fire damage might cause ceramics to change color or to spall (flake or fragment). It could also damage surface decoration. Beyond damage to the materials, fire could also affect thermoluminescence dating, which uses light emitted from an object to determine age.
In addition, organic materials tend to burn at lower temperatures than other types of artifacts. Most Florida sites contain numerous bone and shell artifacts, which could undergo changes in color or appearance. Bone might also shrink or crystallize, which affects the ability to assess it.
Another consideration in assessing wildfire impact is shell heat capacity. Most Florida midden/mound sites are composed primarily of shell materials. However, studies evaluating the thermal conductivity and heat capacity of shells haven’t tested for wildfire situations, which would be a significant factor in evaluating risk for Florida sites.
Even with all these risks and factors still up in the air, the project can go a long way toward helping Florida archaeologists plan for the worst. Archaeologists working within these boundaries can implement fire-resilient site management practices such as vegetation clearing to remove excess duff, and site documentation for previously unevaluated sites. Above all, this project highlights the need for careful and continued site monitoring, especially pre- and postfire, to make sure that Florida’s history is well protected.
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