Using Social and Ecological Data to Identify Trends in Three
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USING SOCIAL AND ECOLOGICAL DATA TO IDENTIFY TRENDS IN THREE MARINE PROTECTED AREAS IN THE GULF OF CALIFORNIA by Caitlin Starks Dr. Xavier Basurto, Adviser April 12th, 2017 Masters project submitted in partial fulfillment of the requirements for the Master of Environmental Management degree in the Nicholas School of the Environment of Duke University ACKNOWLEDGEMENTS I would foremost like to thank my advisers, Dr. Xavier Basurto and Dr. Mateja Nenadovic for their guidance, support and constructive feedback throughout the course of this project. In addition, I would like to express my gratitude to the staff of Comunidad y Biodiversidad, A.C. and Sociedad de Historia Natural Niparajá, A.C. for kindly providing data vital to this study, and to Dr. Daniel Dunn and Dr. Daniel Holstein, who graciously offered me their time and expertise. Finally, I could not have accomplished this work without the encouragement of my parents and my family at the Duke Marine Lab. 2 EXECUTIVE SUMMARY On a global scale, marine protected areas (MPAs) have become an increasingly common tool for marine conservation. While numerous studies have provided evidence of the positive ecological impacts of MPAs, fewer research efforts have focused on how MPAs affect local fisheries and communities. Recent studies suggest that social impacts vary widely within and across communities near MPAs and there is still a lack of understanding of the mechanisms driving these differences. These knowledge gaps are partially due to a lack of data, but also because MPAs are situated in complex social-ecological systems, the structures and functions of which can be difficult to untangle and require different types of data to understand. With this study, I aim to bring disparate data sources into conversation with each other to gain a more comprehensive understanding of the impacts of MPAs on social and ecological systems. I use three sources of data, including interviews with MPA managers and one key informant from a non-governmental organization (NGO), data on fish abundance and biomass at ecological monitoring sites in the MPAs collected by local NGOs, and data from self-reported fishery landings provided by the National Fisheries and Aquaculture Commission of Mexico. Using these existing data, I aim to provide some insight about three MPA cases in the Gulf of California: Cabo Pulmo National Park, Loreto Bay National Park, and Espíritu Santo National Park. Specifically, I aim to identify perceived impacts of the MPAs, ecological changes, and trends in small-scale fisheries landings over time, and compare results across the three MPAs. The interviews are useful to understand attitudes and opinions about the success of these MPAs, but provide an incomplete view as they do not offer information about residents’ and resource users’ perceptions of the parks. The ecological monitoring data allows us to see how fish abundance and biomass change over time in the MPAs and compare the effectiveness of no-take areas to take areas in the parks. However, as monitoring data is only available for a few years it is difficult to identify trends over time. The fisheries landings data, while it offers an opportunity to study trends over a longer period, presents challenges due to inconsistent collection and unknown accuracy. I used a mixed methods approach in my data analyses to explore community, ecological, and fishery changes surrounding the establishment of the three MPAs. In the 3 analysis of the interviews I used NVivo software to categorize the perceived impacts of each MPA by type: ecological, fishery, or social. Then I used regression analysis to illuminate changes in two ecological indicators, biomass and abundance of commercial fish in each park and in both take and no-take zones, as well as changes in small-scale fisheries landings over time. The interviews indicate that the MPA managers and key informants from NGOs perceived mostly positive social impacts, some negative and positive ecological effects, and benefits to fisheries from the three parks. The results of the ecological data analysis are inconclusive; significant changes in abundance and biomass are mostly undetectable. The analysis of the small-scale fisheries landing data suggest a) the total weight of finfish landed at sites surrounding these parks varies and fluctuates across the time series, b) catch per unit effort may be increasing around Cabo Pulmo and Espíritu Santo, and c) fishers generally seem to be earning less value per unit weight of finfish over time. Yet, it is important to consider the findings of this study are limited. The nature of the data and analyses do not allow us to attribute observed changes to the MPAs, but rather offer insight about potential impacts. I recommend further investigation of the trends highlighted through this exploratory analysis to gain a stronger understanding of the effects of the three MPAs studied here. Revised methods and additional data would add strength to these analyses and have the potential to elucidate more conclusive results. Gaining a deeper understanding of the interplay between MPAs and local social-ecological systems through multi-method studies like this will allow conservation planners to enhance the success of MPAs in protecting ocean resources and benefitting coastal communities. 4 Contents INTRODUCTION ............................................................................................................................................. 6 METHODS ...................................................................................................................................................... 8 Study Area ................................................................................................................................................. 8 Focal MPAs: Cabo Pulmo National Park, Bahía de Loreto National Park, and Espíritu Santo Archipelago National Park ........................................................................................................................................... 10 Data Collection and Analysis ................................................................................................................... 12 Analysis of Interviews ............................................................................................................................. 13 Analysis of ecological monitoring data ................................................................................................... 13 Analysis of fishery landings ..................................................................................................................... 14 RESULTS ...................................................................................................................................................... 17 Perceived Impacts of MPAs .................................................................................................................... 17 Interview Results: Cabo Pulmo ........................................................................................................... 17 Interview Results: Bahía de Loreto ..................................................................................................... 18 Interview Results: Espíritu Santo ........................................................................................................ 19 Trends in Ecological Monitoring Data ..................................................................................................... 20 Ecological Trends: Cabo Pulmo ........................................................................................................... 20 Ecological Trends: Bahía de Loreto ..................................................................................................... 21 Ecological Trends: Espíritu Santo ........................................................................................................ 21 Trends in Small Scale Fisheries Landing Data ......................................................................................... 27 Effort Estimation ................................................................................................................................. 27 Fisheries Trends: Cabo Pulmo ............................................................................................................. 27 Fisheries Trends: Bahía de Loreto ....................................................................................................... 30 Fisheries Trends: Espíritu Santo .......................................................................................................... 30 DISCUSSION ................................................................................................................................................. 34 What are the impacts of these parks as perceived by MPA managers and key informants? ................ 34 What can ecological monitoring data tell us about ecosystem changes around the MPAs? ................. 36 What trends in fisheries can we identify surrounding the creation of these MPAs? ............................. 38 How do results for each of these MPAs compare to each other? .......................................................... 39 Lessons Learned ...................................................................................................................................... 40 REFERENCES ...............................................................................................................................................