11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 17: Emerging Techniques in Remote Sensing and Geospatial Analysis
17.557
Reef Mapping Technologies For Marine Management in Brazil And Belize
John MUSINSKY 1 , Debra FISCHMAN* 1 , Daniel KLEIN 2 , Guilherme Fraga DUTRA 3 ,
Rodrigo MOURA 4 , Phillip LOBEL 5 , Peter STETSON 5 , Alex BASTOS 6 , Ruy KIKUCHI 7
1 Center for Applied Biodiversity Science, Conservation International, Arlington, VA,
2 Conservation International Brazil, Caravelas, Brazil, 3 Conservation International Brazil,
Ondina, Salvador, Brazil, 4 Conservation International Brazil, Caravelas, BA, Brazil,
5 Department of Biology, Boston University, Boston, MA, 6 Department of Geology,
Universidade Federal do Espírito Santo, Goiabeiras, Vitória, Espírito Santo, Brazil,
7 Instituto de Geociências, Universidade Federal da Bahia, Salvador, BA, Brazil
This poster describes and compares different types of reef and inter-reefal mapping and
monitoring technologies being used to support the Marine Management Area Science
Program, a scientific effort coordinated by Conservation International seeking to
understand and improve management effectiveness and design of marine management
areas. In two study areas, the Abrolhos Bank (Brazil) and the Mesoamerican reef
(Belize), a combination of high-resolution optical satellite imagery, side-scan sonar,
multi-beam echo sounder, remotely operated vehicle (ROV), and SCUBA dives (for
video and photographic records) are being used to map and validate classification of
shallow (up to 20 meters) and mid-depth (up to 100 meters) coralline and inter-reefal
habitats. These technologies were chosen for: 1) their ability to map extensive
geographic areas; 2) their capacity to provide high-quality information; 3) their suitability
to the varying environmental conditions of the reef and inter-reefal areas; and 4) cost and
availability. For shallow coral reef systems, QuickBird and IKONOS satellite images are
being used to classify fine-scale biophysical characteristics (e.g. macroalgae, corals, sand,
mud) and create a baseline map for long-term monitoring of these reefs. We are
systematically sampling deeper benthic habitats with side-scan sonar profilers and
acoustic doppler topographic survey devices to detect potential reef structures and map
bottom types. Anomalies and prominent features (e.g. pinnacles, channels) identified in
the acoustic mapping surveys are subsequently ground-truthed using SCUBA dives to 60
m and ROV coupled to video cameras to 100 m. Comparisons between the technologies
used and their appropriateness for the different habitat mapping objectives are discussed.
17.558
Habitat Isolation Negatively Influences Reef Fish Populations Of A Hawaiian Atoll
Erik FRANKLIN* 1
1 Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI
Experimental studies have demonstrated that reef fish richness and abundance tend to be
greater on more isolated reefs. The relatively small spatial scale of these experimental
studies may have led to results not applicable to the scales and distribution of natural reef
areas. A thematic benthic habitat map derived from an IKONOS satellite image was used
to define a sampling domain to test a hypothesis regarding the influence of isolation on
reef fish among natural reef habitats. Fish populations associated with fourteen reef
patches of similar size and biogeomorphological characteristics were surveyed within the
lagoon at Midway Atoll in July 2007. Reef fish populations were assessed using a visual
belt transect method that recorded the size and species of each individual. In contrast to
other studies, a gradient of decreasing abundances and fish sizes coincided with greater
habitat isolation. The trend in species richness with isolation was not as strong. These
results suggest that habitat isolation can have a negative effect on fish communities if
examined at spatial scales that may better reflect the inaccessibility of adjacent habitat
patches from the reef fish perspective.
17.559
Assessing Florida and Hawai'i coral reef ecosystem health using a GPS-based underwater
video mapping system
Paul AYERS* 1 , Rebecca MESSER 1
1 University of Tennessee, Knoxville, TN
Assessing and monitoring coral reef ecosystem health is essential for understanding immediate
and long-term environmental impacts. An Underwater Video Mapping System (UVMS) is a
technique to acquire Global Positioning System (GPS)-based georeferenced underwater images
that allow mapping of underwater features. The system automatically interfaces the GPS and
underwater video image providing a location for each picture. Using the UVMS, underwater
features essential for assessing and monitoring coral reef ecosystem health can be acquired and
mapped using Geographic Information System (GIS).
The UVMS was used to acquire georeferenced underwater images in sections of the coral reef
ecosystem in Moloka'i, Hawaii and Biscayne National Park (BISC), Florida. In BISC,
increasing swath width from 20 meters to 40 meters decreased substrate map accuracy from
93.4% to 73.6%. In Moloka'i, dense coral was observed for 40% of the transect, and sand with
algae represented 13% of the survey site.
In addition to mapping of substrate conditions, factors contributing to the assessment of coral
reef health were identified and mapped. These features include marine debris (discarded items
including ropes, traps, etc.), coral damage (from boat, anchor, etc.), coral disease and other
health issues (i.e. black band disease). In the 0.2 square km survey within BISC, 8 locations of
black band disease were recorded. In a 1.7 km transect over Pacific Reef, 9 observation of
marine debris were mapped.
The UVMS is a useful tool for providing large-scale assessments of the coral ecosystem health,
and identifying areas that need further detailed investigation. It also provides a georeferenced
video history of coral health and an opportunity to resurvey the same coral reef ecosystem and
monitor health changes.
17.560
Comparison Of A Benthic Terrain Model To Benthic Habitat Classification Maps Of
Moloka‘i, Hawai‘i, Usa
Susan A COCHRAN* 1
1 USGS Pacific Science Center, Santa Cruz, CA
A study was undertaken to compare modeled morphological complexity of a coral reef to
benthic habitat maps to investigate patterns of habitat preference. Using the Benthic Terrain
Modeler (BTM), an extension created for ArcGIS by the joint efforts of the seafloor-mapping
lab at Oregon State University and NOAA’s Coastal Services Center (Wright and others, 2005),
a benthic terrain model of the fringing coral reef on the south shore of Moloka‘i was created
from high-resolution SHOALS lidar bathymetric data (~2.5 m spacing between data points).
The BTM classifies data based on a combination of slope (a first-order derivative of
bathymetry), broad- and fine-scaled bathymetric position indices (BPIs, second-order
derivatives of bathymetry) describing the depth of a specific point relative to the surrounding
bathymetry, along with rugosity, and produces grid layers of terrain-based zones and structures.
Modifications were made to the default classification scheme provided with the BTM tool to
better reflect the changes in depth and slope found on the Moloka‘i fringing reef.
The results from the BTM were compared to high-resolution (100 m 2 Minimum Mapping Unit)
benthic habitat classification maps of Moloka‘i (Cochran-Marquez, 2005), to determine
relationships between mapped benthic habitats and modeled BPI structures. Areas that were
mapped with high coral cover were found to be the areas of highest morphological complexity
in the terrain-based model. Establishing associations between benthic coverage (and in some
instances percent cover) and modeled structures and zones will allow users to extend mapping
capabilities to areas where field validation of remotely-sensed underwater resources is limited.
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