Ancient Shoreline Erosion
By Sarah Rosenbaum
Calusa artifacts (Bob Reid/flickr @paladinsf).
You can find artifacts from ancient people in nearly every part of the world. In most of America, the typical artifacts often found are stone-carved arrowheads, spearheads, pottery remnants, and perhaps some carved bone items.
Detail from 1591 map of Southern Florida showing the “Calos” tribe (De Bry and Le Moyne).
In Southwest Florida, the Calusa tribes were the dominant coastal people for hundreds and possibly thousands of years before the Europeans arrived. Their population was believed to exceed 20,000 at one time.
Calusa tribes have captured the attention of historians because of their unusual and innovative lifestyle. Most indigenous people groups were hunter-gatherers who also utilized agricultural skills to grow their food and work the land to some degree. The Calusa, however, were hunter-fishermen who developed possibly one of the most complex societies that did not depend on agriculture at all. How did they thrive for so long in the Florida environment without the practices we see in other early societies?
Shell middens exposed by storms and hurricanes (Sarah Rosenbaum).
Recent storms and hurricanes in Southwest Florida have begun to tear up more and more of the coastline. Nearby shoals believed to have once been shell middens for the Calusas are being unearthed, and more clues about their mysteries come with each wave.
A midden is a dump where people disposed of their domestic waste. Shell middens contain the cast-off shells from seafood, along with other rubbish such as bones, broken tools, human waste, and more. We can learn much about the people through shell midden excavations. Most of the items uncovered from Calusa sites and middens are tools, equipment, seashell jewelry, and kitchen waste.
Fish captured with nets by the Calusa in a nearshore environment (Merald Clark/Florida Museum of Natural History).
Watercourts
The Calusa created structures to capture and raise fish in walled aquatic pens called watercourts. Built on top of oyster beds, they trapped fish that floated in during especially high tides. Surplus fish were dried in order to store and transport them. The Calusa used dugout canoes to travel, venturing as far as modern-day Havana, Cuba, to conduct trade.
Wooden Artifacts
In early excavations of the Marco Island sites, many of the wooden artifacts were pulled from the mangrove peat completely intact, with all their colors and paint perfectly preserved. However, once the items were exposed to the elements, they deteriorated quickly. The Marco Island Historical Museum lays out the process used by the excavators to photograph and paint likenesses of the pieces as they were being brought out of the mud, so that the deteriorating pieces could be replicated with as much accuracy as possible later on. Their museum is free to the public and includes a wonderful life-sized Calusa village replica so one can see how life in Florida may have been in ancient times.
Left to right: Sarah Rosenbaum. Bob Reid/flickr @paladinsf.
Shell Artifacts
The great thing about shell artifacts is that they take a very long time to naturally break down, allowing scientists to study them for as long as needed. The artifacts washing up in the Ten Thousand Islands today are shells of mollusks that could have been eaten and/or used as tools 1,500 to 3,000 years ago!
Left to right: Bob Reid/flickr @paladinsf. Sarah Rosenbaum. Sarah Rosenbaum.
The most common find for me so far has been hammer tools made from large whelks and conchs. These large shells were punctured and chiseled to form a large hole at the top allowing a stick to be pushed through the hole and attached with cordage. The shells would then effectively become hammers or, when the siphon canal or “tail” of the shell was sharpened, it could be used to cut, puncture or carve other objects. The blunted edges of these hammer tools are still visible today.
Left to right: Key Marco Cat (Department of Anthropology, Smithsonian Institution). Sarah Rosenbaum. Sarah Rosenbaum.
Famous Calusa artifacts such as the wooden Marco Cat, masks, and hammer tools have been found all along the southwest coast of Florida. The most famous Calusa shell mound is Mound Key, which is a designated archaeological Florida State Park and can only be accessed by water. Other sites include Key Marco (near Marco Island) and the Mound House in Fort Myers Beach. Each of these mound sites provides unique insight into Calusa life—however, over time and with the consistent weathering of the coast, more and more sites may be uncovered.
The Ten Thousand Islands has a rich history as a navigation point into the southern waterways of Florida, and with the new and incoming artifacts washing ashore, it’s very possible we may uncover more mound sites in the future.
Note
It is unlawful to collect specific archaeological artifacts in many areas in Florida, and regulations are strictly enforced. While it is exciting for beachcombers to find artifacts, especially because the hammer tools are often made of large shells, I discourage the collection of such finds. All photographed artifacts were reported to the local archaeological teams and returned to their place after being photographed. In the event of an archaeological survey, the importance of leaving these artifacts exactly where they were found cannot be stressed enough.
This article appeared in Beachcombing Magazine Volume 41 March/April 2024.
