We gathered a time series of aerial photographs, mapped coral reefs, mangroves, and seagrasses, and summarized previous ecological studies into a descriptive report for use by scientists and resource managers.
Why We Care
The National Park Service Salt River Bay National Historical Park and Ecological Preserve (SARI) in the U.S. Virgin Islands was created in 1992 to preserve and protect the area’s natural, historical, and cultural resources. The diverse ecosystem at SARI includes a large mangrove forest, submarine canyon, coral reefs, seagrass beds, coastal forests, and developed areas. These habitats are host to a great diversity of plants and animals that combined represent a regional hotspot of biodiversity. To make informed decisions about ecosystem management, park personnel needed comprehensive data to understand the complex activities and interactions taking place within the preserve’s diverse habitats.
What We Did
Our characterization of the park's ecological resources consisted of three complementary components: a text report summarizing previous ecological studies, digital habitat maps, and a collection of historical aerial photographs. The text report was divided into sections based on physical characteristics, habitat types, and major faunal groups. We created the park’s habitat maps from a collection of 184 aerial photographs of the area dating from the 1970s to 2000, using the most current photographs to create a separate map of 50 terrestrial and marine habitat types visible in the imagery. This combination resulted in the first detailed spatial characterization of the SARI ecosystem. We also developed a time series of photographs to create maps of seagrass and mangrove changes that had occurred since the 1970s. This particular group was used to frame the discussion of each major habitat type, faunal group, or environmental category in the report.
What We Found
The complementary aerial imagery, habitat maps, and text report we developed provided research, monitoring, and management tools for park officials. The images could be used to map additional ground features, document historical changes, and serve as a baseline against which future imagery could be compared. Habitat and land cover maps were created to assist with the design of monitoring schemes, selection of research sites, and identification of potential habitats for species of interest. The discussion and analyses contained in the text highlighted established knowledge, explored spatial aspects of previous research, and identified information gaps and threats that could guide future monitoring and research. Together, these components provided a variety of information to facilitate the current and future stewardship of the diverse resources contained within SARI. Much more detailed methods and results are accessible in the report (see link below), including other characteristics of SARI, such as birds, land cover, soils, land use, and geology.