The Use of Remote Sensing and GIS in MPA Delineation and Management

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1 Claire Hodson The Use of Remote Sensing and GIS in MPA Delineation and Management Marine Protected Areas (MPAs) are often defined as clearly distinct geographical space, recognized, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values (ICUN). MPAs have become increasingly significant in the management of marine spaces as the conflict between human development and the environment continues to intensify. Currently, thirty-nine percent of the world s population lives within 100km of the coast and eight percent lives within 100km of a coral reef and these numbers are growing every year (Guebad-Dahdough, 2002). This growth has resulted in significant environmental degradation such as declining fish stocks and significant loss of marine biodiversity and habitat at the hands of destructive fishing practices, overfishing, siltation, and pollution (Rubec et al., 2009). MPAs are an attempt to minimize the human influences that cause these problems but MPA management is not without weakness. MPAs are often created without significant information concerning the locations of benthic habitats, their associated marine resources and the use of those resources by local communities. GIS and remote sensing help to ameliorate such knowledge lapses. Remote sensing helps managers determine where an ecosystem might be vulnerable or degraded by creating habitat maps. The application of GIS combines local environmental knowledge, such as where in the reef one might find the most grouper or what areas are more easily accessed by fishermen, to create a visual representation of local human influences and dependencies. These two types data bridge the gap between people and the environment and thus, are utilized by managers to create an effective co-management plan for proposed and existing MPAs. In regard to MPAs, remote sensing is collection and analysis of imagery obtained from satellites, aerial photography, sonar and aerial hyperspectral sensors. However, the studies read for this paper focus solely on satellite imagery and aerial photography. While the application of remote sensing is very broad, coastal and fisheries management primarily use this data to create benthic habitat maps, formulate more efficient stratified random sampling of fish species, and better comprehend the spatiotemporal relationship between natural and human-based spaces (Guebad-Dahdough, 2002). Determining the type and density of habitat features is an important tool in evaluating the health of an ecosystem, where it may be vulnerable, and any long and short term changes that may occur. Early studies evaluating the use of satellite imagery to delineate habitat types showed that Landsat TM and SPOT HRV sensors only allowed discrimination of broad categories of benthic habitat such as coral, sand, sea grass, and sometimes, algae (Rubec et al., 2009). However, the better spatial resolution of the IKONOS and QuickBird satellites has increased classification accuracies to 75-80% using broad substrate classes. For high complexity mapping, studies show that IKONOS performs best (Rubec et al., 2009). IKONOS imagery can facilitate the special delineation using GIS of benthic habitats such as patch reef, fore reef, spur and grove reefs, back reef areas, forests etc. (Rubec et al., 2009). This is useful in figuring out which areas have a high vulnerability to anthropogenic influences, and consequently, which areas managers should focus their resources on. Additionally, benthic habitat is a major indicator of fish assemblage structure in the marine environment. Thus, documenting location habitat in an MPA can provide insight into species distribution, biodiversity, and habitat connectivity. In 2000, the NOAA Operation Center s aircraft, along with the National Geodetic Survey cameras and personnel, acquired color aerial photographs at 1:24,000 scale for much of the Hawaiian Islands (Wedding et al., 2011). From these images, researchers from the University of Hawaii created fish population estimates from the delineation of benthic reef

2 habitats. They then collected fish population data through observation studies to test the accuracy of their habitat maps and subsequent predictions. The results found that estimating fish populations from benthic habitat maps derived from aerial photographs as a resolution of 1m x 1m is 88% accurate (Wedding et al., 2011). In addition to this study, researchers used the benthic habitat classes as strategy for a stratified random sampling design in order to produce more accurate, more efficient fisheriesindependent data (Wedding et., al., 2011). As a result, researchers determined that MPA managers in both data rich and data poor countries can gain significant fish population and reef health data from remote sensing, greatly increasing the resources and data available for management programs. Remote sensing can also aim to determine the success of an MPA and any regulation changes that can be made to help alleviate the conflict between natural resources and the consumption of those resources. One study in Kenya used aerial photography to determine the land-use and productivity of the area in and around the Kiunga Marine Protected Area (Guebad-Dahdough, 2002). The photographs were analyzed with special attention to tonality, crown texture, structure and tree height relative to position in order to determine different types of mangrove trees and their density. This data was stratified into forested vs non-forested (agricultural and water) areas and productive vs. non-productive forests (Kairo et al., 2002). This stratification and the creation of habitat maps using GIS made it possible to see which mangrove habitats have been restored and/or are healthy and which are not. Researchers found that mangroves in and directly adjacent to the MPA had a high productivity and regeneration rate and as a result, those forests were capable of handling a higher level of sustainable exploitation (Kairo et al., 2002). Regulations were changed to accommodate these findings. Remote sensing is an efficient tool in collecting environmental data in coastal marine ecosystems. However, MPA management relies heavily on human influences on the environment and community cooperation. GIS allows managers to incorporate socio-spatial in formation such as indigenous ecological knowledge and artisanal fishing data into biophysical data to identify sites that support biodiversity, include the presence of exploitable species, vulnerable life-stages and interconnectivity among habitats and the needs of the local people. In essence, GIS helps managers determine where an MPA would work best for the environment and the people. A study looking at previously chosen MPA locations in the Solomon Islands used GIS to incorporate fishermen behavior and local knowledge into a re-evaluation of these delineations. Data was collected through direct participation in fishing forays and though oral interviews with fishermen (Aswani and Lauer, 2006). Fishermen identified about 14 major habitats, 6 minor habitats and 615 locally delineated areas in the two lagoons studied, the Raviana and Vonavona Lagoons. These locally designated areas were mapped into aerial photographs of these lagoons manually. Fishermen then went out with researchers and, using handheld GPS devices, recorded the locations of spawning, nursery, burrowing and aggregate sites for particular species within each recognized area (Aswani and Lauer, 2006). The resulting paper locally classified benthic maps were scanned and loaded into GIS for image rectification. Researchers then accompanied fishermen to the fishing grounds to collect another series of data that looked at the spatio-temporal behaviors of the fishermen, i.e. fishing pressure and mean rate of return per hour of fishing per season for each locally delineated fishing area (ran a GIS query to get the mean/season). Through the combination of each map, managers were able to determine if the previously designated MPA areas were right for the environment and right for the people. For the Raviana Lagoon, near the Baraulu Village, the passage was the previously discussed MPA site but the research found that it was the most heavily used zone year round and, on average, had the highest mean rate of return per hour fishing (Aswani and Lauer, 2006). Therefore, establishing an MPA there would have been met with community resistance because a fishing closure would have greatly affected the livelihood of the community. As a result, managers chose a different spot that was still heavily fished but less vital for subsistence (Aswani and Lauer, 2006).

3 Adhering to the needs of the local people and the environment is crucial in creating a successful management plan because without the cooperation of the local people, the environment will not benefit, and without a healthy environment, the local people will not be able to thrive. The ability of ability to GIS to restore, retrieve, analyze and display spatial and social characteristics of complex systems makes it an excellent tool for deepening our knowledge of the socio-ecological dimensions (Aswani and Lauer, 2006). Similarly, remote sensing is an efficient and accurate way of acquiring habitat data on the areas in question. For many developing countries, large-scale data acquisition is simply not practical because of a lack of resources. As a result, management of marine ecosystems is incredibly deficient. The future of the use of remote sensing and GIS in MPA delineation and management lies in making the data more affordable and more easily acquired for developing communities. Satellite imagery is getting more and more resolute and with the growing popularity of drones, prices will go down and quality of aerial photography will improve drastically. It is my belief that for small-scale, developing fisheries, drones are going to be a stepping stone for better management. However large-scale, more complex analyses, satellite improvements are going to be revolutionary in habitat mapping and like using remote sensing in agriculture, remote sensing in MPAs will be able to determine which corals are healthy and which are not. As I said early, 39% of the world lives within 100km of the coast and many of these communities are in developing countries. That is nearly 3 billion people, many of whom do not have the resources or data to try to conserve the environment they are destroying. Remote sensing and GIS are the tools that will universalize MPA management and create an interface between people and the environment. It is this incorporation of the social and the environmental that will determine the success of any environmental management initiative. Annotated Bibliography Aswani, Shankar, and Matthew Lauer. "Incorporating Fishermen s Local Knowledge and Behavior into Geographical Information Systems (GIS) for Designing Marine Protected Areas in Oceania." Human Organization 65.1 (2006): Web. In this paper, Shankar and Lauer discuss how GIS can be a useful tool in combining peoples knowledge and socioecological behavior into a visual representation of geo-spatial data. This allows researchers to formulate hypotheses regarding human responses to inter- and intra-habitat variability, along with other marine ecological processes, and help in the designing and implementation of resource management strategies in a cost-effective and participatory way, bridging the gap between indigenous and Western ideas of seascapes. This paper demonstrates the oral interviews researchers used to evaluate local fisherman behavior. It also describes the participatory research that went into the delineation of where, in the fishermen s experience, the reef and surrounding area was biologically productive. GIS analysts created two sets of maps from this data. One showed where fishermen fished and where they knew there to be fish. The other analyzed fishing pressure in each area through out the year. By using this data, coastal managers changed the area in which they had previously proposed an MPA because they found that it would have had significant effects on the livelihood of the local community.

4 Dahdough-Guebas, The Use of Remote Sensing and GIS in the Sustainable Management of Tropical Coastal Ecosystems. Environment, Development and Sustainability 4 (2002): This paper discusses the importance of GIS and remote sensing in understanding the direct impacts of human influence on coral reef ecosystems, the ecosystems reliance and recovery capacity following such impacts and the efficacy of management measures to ameliorate impacts. It highlights a selected number of remote sensing case-studies on land cover patterns, population structure and dynamics, and stand characteristics from South-East Asia, Africa and South-America, with a particular emphasis on mangroves. This includes changes in population structure of floral and faunal assemblages, changes in biodiversity and ecosystem functioning, and the influences of anthropogenic activities on this ecosystem. The paper compares case studies that use solely aerial photography with others that incorporate IKONOS satellite imagery. The purpose of this comparison is to demonstrate the complexity of analyzing habitats using remote sensing data and provide guidelines for the development of the use remote sensing in areas where resources are limited. Ultimately, the author emphasizes the use of remote sensing technology in predicting degradation and how this technology might be used to build anticipatory management strategies. Kairo, J.G., et al, Application of Remote Sensing and GIS in the Management of Mangrove Forests Within and Adjacent to Kiunga Marine Protected Area, Lamu, Kenya. Enviornment, Development and Sustainability 4 (2002): This paper focuses on the science applications of remote sensing and GIS in the creation of a management plan for the previously undermanaged mangrove ecosystems within and adjacent to the Kiunga Marine Protected Area. Medium scale black and white panchromatic aerial photographs were used to derive vegetation maps of mangrove forests. The analysis of the aerial photography was stratified to differentiate between forested and agricultural land and determine the biological productivity of those spaces that analysts determined to be mangrove forests. Analysis of these areas pays special attention to tonality, crown texture, structure and tree height relative to position in order to distinguish between different species of mangroves and formulate density ratios. The study found that most mangrove forests in and around the Kiunga MPA has high productivity and regeneration potential which enabled managers to assume that those areas would thrive under regulations than ensured sustainable exploitation opposed to no-take zones. Wedding et al., Integrating remote sensing products and GIS tools to support marine spatial management in West Hawai`I. Journal of Conservation Planning 7 (2011): This paper discusses the use of GIS tools in creating and enhancing benthic habitat maps to provide accurate and up-to-date data on the geomorphic over and biological productivity. Researchers combined aerial imagery, underwater video, MPA regulations, summarized ecological data and other relevant and spatially explicit information. Benthic habitat is a strong indicator of the fish assemblage structure and thus fisheries scientists can estimate fish populations from remote sensing imagery. The goal of this paper was to create a database detailed, near-scale benthic habitat maps for a network of MPAs in West Hawai`i in order to determine fishing regulations within MPAs and analyze any changes caused by this management. They tested the accuracy of the relationship between habitat and fish productivity by comparing the data delineated from the benthic habitat maps to SCUBA observation studies of the areas in question. The study found that GIS-based benthic mapping is highly accurate

5 spatially and as a method of estimating fish populations. In addition to this study, researchers used the benthic habitat classes as strategy for a stratified random sampling design in order to produce more accurate, more efficient fisheries-independent data Rubec, Peter et al., The Use of Remote Sensing and Geographic Information Systems to Support Spatial Management and Conservation of Marine Resources in Tropical Countries. WOC (2009) This paper discusses the use of satellite imagery to delineate study areas and create habitat profile to help determine vulnerable areas and potential management initiatives. Rubec quotes lack of data as being a significant weakness in MPA management and often times, a hindrance to the success of ecosystem restoration. He believes that remote sensing is an efficient way to acquire the necessary data. In this study, researchers focus on IKONOS satellite imagery because it allows the most specific classification of benthic features. According to previous studies, the better resolution of IKONOS satellite imagery has increased classification accuracies to 75-80% using broad substrate classes (patch reef, fore reef, spur and grove reefs, back reef areas, forests etc.) They use this imagery and underwater surveys in depleted fisheries in Indonesia and the Philippines in order to estimate population numbers of fish and invertebrates as a function of habitat. Additionally, this paper briefly delves into the use of GIS in participatory coastal resource appraisal where fisherman provide detailed information on their fishing behaviors. Researchers hypothesize that the combination of remote sensing and GIS data will provide adequate information for an affective management plan and is capable of predicting habitat complexity at a scale that is relevant to fish.