Mapping and GIS Capacity Building in American Samoa

Quick Reference

Panoramic digital photo mosaic showing Tutuila, American Samoa in the distance.
Photos taken at sea aboard the R/V Roger Revelle by Stassia Samuels, National Park of American Samoa, March 2002

Of major significance has been the establishment in 2001 of an American Samoa GIS User Group (Table 1), which has facilitated management of several of the aforementioned environnmental issues and responsibilities. Led by the American Samoa Government's Department of Commerce and comprised of ~30 representatives from the various government agencies, as well as the American Samoa Community College, the group performs a variety of important digital mapping and spatial analysis tasks, including: inventory and organization of existing data; development of a land information system; wetlands delineation maps for Tutuila; and the use of satellite imagery to update territory base maps.

Table 1. Agencies with interest or current participation in the American Samoa GIS User Group

The inception of the user group was serendipitously coincident with recent bathymetric surveying around the island, leading further to the establishment of a FBNMS GIS (Wright et al., 2002), as well as renewed interest in the territory by NOAA and the USGS in connection with the pressing need to now to monitor and protect Pacific coral reefs (Anderson, 1999; U.S. Coral Reef Task Force, 2000). In the spirit of "enterprise GIS" (i.e., GIS used by multiple agencies within an organization, or in this case, within a territory), the paper will attempt to review some of the recent developments.

Initial Bathymetric Mapping and a FBNMS GIS

Logistics and scheduling have prevented a visit to the FBNMS by a NOAA research vessel with the DeepWorker submersible, but the author, as an SSE collaborator, teamed with FBNMS manager Nancy Daschbach, and University of South Florida (USF) scientists David Naar and Brian Donahue, to undertake successful bathymetric surveys and the initiation of a FBNMS GIS in April and May of 2001. Until recently the sanctuary, as well as the national park were largely unexplored below depths of ~30 m, with no prior bathymetric base map in existence and no comprehensive documentation of undersea flora, fauna, and habitat. The team used a Kongsberg-Simrad EM 3000 portable multibeam bathymetric mapping system, attached to the bow of a 30-foot survey boat loaned by the Department of Marine & Wildlife Resources (DMWR) of the America Samoa Government. Further details of the logistics of the survey may be found in Wright et al. (2002).

In 2 weeks of surveying, full bathymetric coverage was obtained around selected sites off the main island of Tutuila, American Samoa: the FBNMS in the southwest, part of the National Park along the north shore, Pago Pago harbor and Taema Bank to the south, and Faga'itua Bay in the southeast (Figure 1). Post-processing steps after the surveys were completed included the "cleaning" of the navigation to delete erroneous positions, then tidal corrections were applied to the depth soundings using NOAA, verified downloaded tide data available for the study area. ASCII formatted x-y-z depth data were then gridded using MB-System, a public-domain suite of software tools for processing and display of swath sonar data. Initial maps made from the grids with Generic Mapping Tools (GMT) revealed many important features such as reef terraces, erosional remnants, volcanic edifices, and blocks of reef debris (e.g., Figure 2). Mapping of the Pago Pago harbor also captured in striking detail the wreckage of the USS Chehalis, a WWII oil and gas tanker that exploded and sank in the harbor in 1949, and may be still be a source of water pollution (Figure 3).

Figure 1. Index map of Tutuila, American Samoa with pink circles showing the locations of recent multibeam bathymetric surveys around the island. Inset photograph at lower left is an aerial shot of the FBNMS (photo courtesy of the FBNMS, www.fbnms.nos.noaa.gov). Codes for other survey areas: NP = National park of American Samoa (total area of submerged national park offshore Tutuila is ~5 sq. km); PPH = Pago Pago Harbor; TB = Taema Bank; FB = Faga'itua Bay. Map is based on a U.S. Geological Survey (USGS) 10-m digital elevation model (DEM) provided by A. Graves of Nuna Technologies, American Samoa.

Figure 2. Histogram equalized, shaded relief bathymetric map of Taema Bank, a drowned coral reef terrace located ~3 km off the south central coast of Tutuila.

Figure 3. Color-shaded, sun-illuminated bathymetric map featuring the wreck of the USS Chehalis in Pago Pago Harbor (cartography by B. Donahue). Inset photo of a ship in the same class as the USS Chehalis courtesy of the U.S. National Archives and Records Administration.

Bathymetric grids were then converted with ArcGMT, a public-domain suite of tools for converting GMT-style grids to Arc format. These bathymetric grids constituted the base layers for the FBNMS GIS (Wright et al., 2002), which also included an initial compilation of terrestrial data layers, including a 10-m digital elevation model of Tutuila, various digital line graph and digital raster graphics files, shapefiles, coverages, and grids, all obtained from the National Park Service, the USGS, the Digital Chart of the World, and other sources.

In order to make all data sets in the FBNMS GIS accessible, not only to the sanctuary staff and their collaborators in American Samoa, but to collaborators throughout Oceania and the U.S., a web clearinghouse was built ((dusk.geo.orst.edu/djl/samoa), providing links to all of the GIS data and metadata, and to bathymetric grids in GMT format for non-GIS users, various maps, photographic images, and graphics. All GIS data are provided as ArcInfo export interchange files (i.e., *.e00 files), which may be imported into ArcInfo, ArcView, or ArcExplorer.

"Ground-truthing" of bathymetric surveys with photography and videography will be an ongoing endeavor. For example, the new bathymetry of the FBNMS helped to guide the location of a deep-diving mission to the sanctuary on May 16, 2001 (Figure 4). University of Hawaii researcher Richard Pyle used rebreather technology to work underwater for over 3.5 hours (a block of time significantly longer than traditional SCUBA), and collected videotape of coral reef biota and habitats up to a maximum depth of 113 m. Although the diving mission was cut short by poor weather, twelve completely new species of fish were observed in the bay, including seventeen species that had never before been observed in American Samoa, and several species that were previously unknown to the waters of Fagatele Bay.

Datum and Projection Issues

SSE Mission

In March of 2002 SSE led a 1-week SCUBA diving, photography, fish count and public outreach mission to American Samoa. A team consisting of Sylvia Earle (SSE), Kip Evans (SSE), Gale Mead (SSE), Brian Donahue (USF), Laddie Akins (Reef Environmental Education Foundation, REEF), and Nancy Daschbach, made 60 dives were to the sanctuary and several other site around Tutuila, including an extensive collection of underwater video and still images. Species observed and documented included 30-50 species of corals, 4 different shark species, over 200 fish species, and 20 invertebrate species. It is hoped that future activities may be georeferenced for incorporation into GIS (i.e., more ground-truth).

Another activity that took place during the SSE mission was a 1-day multibeam bathymetric mapping cruise aboard the R/V Revelle that, along with other multibeam data mined from archives at the Scripps Institution of Oceanography, enabled complete coverage of the mid- to deeper water flanks of Tutuila (Figure 5). These new data will supplement the aforementioned shallow water surveys that were incorporated into the FBNMS GIS in 2001. During the Revelle cruise, the entire north flank of Tutuila and several deepwater multibeam data gaps along the southern flank were mapped with the Kongsberg-Simrad hull-mounted EM120 system, revealing at least 6 new volcanoes off of the northern flank, as well as the shape of banks along the south flank (Figure 6). Many of these banks are inaccurately located on nautical charts and have never been fully mapped with multibeam bathymetry.

Figure 5. (top) Photo (courtesty of Scripps Instituion of Oceanography) of the 273-foot R/V Roger Revelle used for the deepwater multibeam bathymetric survey around Tutuila in March 2002. (bottom). Shipboard science party (except for the little dude on his mom's lab) for the Tutuila bathymetric survey.

Figure 6. Photograph of raw multibeam bathymetry as it was being plotted in near realtime aboard the Roger Revelle, merely to show extent of data collection during the 1-day survey that circumnavigated Tutuila (photo by A. Graves).

Bathymetry data are still being post-processed, and final maps and GIS grids will be incorporated into the FBNMS and made available on the web in late 2002.

Ongoing Initiatives

• the completion of a spatial data framework endorsed by the Governor of American Samoa.
• an aerial survey of the territory being conducted by the Fish and Wildlife Services.
• appeals to Hawaii and Pacific Basin Islands section of the USGS to make publicly available the actual orthoimagery from which many of the USGS vector products are derived (for better delineation of boundaries, archaeological sites, etc.).
• a memorandum of understanding between the American Samoa User Group and Oregon State University for the exchange of students and researchers, sharing of data and imagery, and the implementation of cooperative research programs.
• new doctoral dissertation research by Eric Treml of Duke University to investigate the ecological connectivity between coral reef systems in American Samoa with GIS, analyze the effects of environmental stressors on these systems, and bring the results to bear on marine protected area designation in the territory (E. Treml, pers. comm., 2002).
• development of customized GIS tools for coral mapping and assessment, shoreline change, hazards (especially vessel groundings and oil spills), land permitting support.

Conclusion

It has been very encouraging to witness the explosion of GIS activity in American Samoa, and this review has in no way been exhaustive. The concept of a "territory-wide" GIS for American Samoa is still developing, and in its current decentralized state, even with the formulation of a user group, a continual challenge will be to get data into the hands of resource managers and community activists, along with the tools and understanding of their usage that will allow them to use the data for effective decision-making. And how to do this while preventing duplication of efforts and services, and avoiding competition for the small number of highly-trained GIS personnel in the territory? One approach may be to take advantage of a student labor pool, both on and off-island, especially via a mentorship or apprenticeship program, supported by academic credits and training. The FBNMS has already initiated this, having provided travel support for OSU students to help with mapping and GIS coordination on Tutuila. Indeed, it has been argued by Oberlin (1996) that "the infrastructure most needed to support the information era is financial, social, and political, not technical."

Acknowledgments

Many thanks to Nancy Daschbach, manager of the Fagatele Bay National Marine Sanctuary with whom the author originally made contact in order to start a wide range of collaborations. Brian Donahue and Dave Naar of the University of South Florida Center for Coastal Ocean Mapping have provided excellent multibeam mapping and data processing support. Ken Crouse of OSU Geosciences is thanked for tireless computer technical support in rebuilding GIS files and software in American Samoa during the summer of 2001. Mark Hayward of American Samoa Government Department of Commerce and Allison Graves of Nuna Technologies and the National Park of American Samoa have been invaluable in providing data and GIS assistance, and are thanked also for fruitful discussions. Allison and Kevin Cronk, the NOAA Pacific Island GIS intern for American Samoa, have worked tireless on procedures for converting from American Samoa 1962 Datum, stateplane coordinates to North American Datum, UTM coordinates. Cindy Fowler and Lori Cary-Kothera are thanked for their leadership of the Pacific Island GIS intern program for American Samoa. Jennifer Aicher, Dave Kulberg, Champion Matu'u, and Florence Lutu (American Samoa Community College), Kevin Cronk (American Samoa Government), and Allison Graves and Stassia Samuels (National Park of American Samoa) are thanked for excellent watchstanding at sea. And finally, Tony Beecham of the American Samoa Department of Marine and Wildlife Resources is thanked for general support and good humor. The author was supported by National Science Foundation (NSF) grant OCE/EHR-0074635, with additional travel funds provided by the Fagatele Bay National Marine Sanctuary. Supplemental ship time for the R/V Roger Revelle in order to complete the deepwater multibeam survey around Tutuila was funded by grants NSF-OCE-0002312 to D. Naar, NOAA-408BNC101000 to D. Wright, and NSF-OCE-0074635 to D. Wright.

References

Anderson, C.L. (ed.), 1999. U.S. All Islands Coral Reef Initiative Strategy: Workshop Report of the University of Hawaii Social Science Research Institute and the Pacific Basin Development Council with the US All Islands Coral Reef Initiative Coordinating Committee, Representing the Territory of American Samoa, the Commonwealth of the Northern Mariana Islands, the State of Hawaii, the Territory of Guam, the Commonwealth of Puerto Rico, and the Territory of the U.S. Virgin Islands, Honolulu, HI, University of Hawaii, online at www.hawaii.edu/ssri/Is_CRI.html

Oberlin, J.L., 1996. The financial mythology of information technology: Developing a new game plan, CAUSE/EFFECT (now EDUCAUSE Quaterly ), 19(1), 21-29, online at www.educause.edu/ir/library/text/CEM9616.txt.

Smith, W.H.F. and D.T. Sandwell, 1997. Global seafloor topography from satellite altimetry, Science, 277:1957-1962.

U.S. Coral Reef Task Force, 2000. National Action Plan for Coral Reef Conservation, Washington, DC, U.S. Department of the Interior, online at CoralReef.gov/doc.cfm.

Wright, D.J., B.T. Donahue, and D.F. Naar, 2002. Seafloor mapping and GIS coordination at America's remotest national marine sanctuary (American Samoa), in Wright, D.J. (ed.), Undersea with GIS, Redlands, CA, Esri Press, 33-63.

BACK TO TOP

Panoramic digital photo mosaic from aboard the RV Revelle by Stassia Samuels, National Park of American Samoa, March 2002