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The damage and loss of coastal archaeological sites from shoreline transgression and other near-coastal processes is common around the world. It negatively impacts our ability to address important research questions including those about the colonization of the New World, which likely occurred along the Pacific Coast. Differences in geomorphic context, annual weather patterns, topography, vegetation, bedrock, and land-use history lead to distinct localized patterns of erosion even within small geographic regions. We assessed near-coastal erosion on Santa Rosa Island, California, by monitoring annual change at 16 controlled points on 11 archaeological sites from 2013 to 2017 and by comparing it to the local geomorphic context and annual weather patterns. Overall, erosion through this period was greatest on the northwest coast of the island, which is directly in the path of prevailing winds and most winter storms, and least on the more protected west and south coasts. The 2016–2017 winter was the rainiest and had the most annual erosion in general; however, erosion at sites along gulley walls was lowest that year. By monitoring annual erosion and weather and associating them with variations in erosional processes, we can better understand threats to valuable cultural resources and take appropriate steps for mitigating their losses and the loss of archaeological data.
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Monitoring Shoreline Erosion at Calusa Island: A Community-Accessible Method
Abstract At coastal archaeological sites, measuring erosion rates and assessing artifact loss are vital to understanding the timescale(s) and spatial magnitude of past and future site loss. We describe a straightforward low-tech methodology for documenting shoreline erosion developed by professionals and volunteers over seven years at Calusa Island Midden (8LL45), one of the few remaining sites with an Archaic component in the Pine Island Sound region of coastal Southwest Florida. We outline the evolution of the methodology since its launch in 2016 and describe issues encountered and solutions implemented. We also describe the use of the data to guide archaeological research and document the impacts of major storms at the site. The response to Hurricane Ian in 2022 is one example of how simply collected data can inform site management. This methodology can be implemented easily at other coastal sites at low cost and in collaboration with communities, volunteers, and heritage site managers.
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- Award ID(s):
- 2304807
- PAR ID:
- 10650741
- Publisher / Repository:
- Cambridge University Press
- Date Published:
- Journal Name:
- Advances in Archaeological Practice
- Volume:
- 12
- Issue:
- 3
- ISSN:
- 2326-3768
- Page Range / eLocation ID:
- 289 to 301
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1017/aap.2024.17
