Effective Protected Areas for the Conservation of Amazonian Freshwater Dolphins

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1 Effective Protected Areas for the Conservation of Amazonian Freshwater Dolphins Vanessa Jordan Mintzer University of Florida, Colombia SUMMARY I will evaluate if the Mamirauá Sustainable Development Reserve in the Western Brazilian Amazon is providing ecological and conservation benefits to the two Amazonian river dolphin species, boto (Inia geoffrensis) and tucuxi (Sotalia fluviatilis). I will determine home range size and analyze movement patterns of river dolphins, determine if and how Mamirauá is influencing fisher attitudes and conservation behaviors, and construct a spatially explicit population model to evaluate different reserve scenarios. The overall goal of my study is to investigate and highlight the reserve design elements that are vital for the establishment of effective freshwater dolphin protected areas. DESCRIPTION Introduction Protected areas (PAs) are recognized as a tool for the conservation and management of cetacean populations (Barlow 2002, Hoyt 2005). However, currently there is a lack of freshwater protected areas (FWPA) established and managed specifically for the conservation of Amazonian freshwater dolphins, the boto (Inia geoffrensis) and the tucuxi (Sotalia fluviatilis). Despite the fact that both species are expected to be relatively abundant in most of their historical range, concern for these animals has grown in the past few years due to increasing threats. Deliberate killing of botos for fish bait is a growing and alarming problem. Boto carcasses are being used to attract the catfish commonly known as piracatinga,mota, simi, or mapurite (Calophysus macropterus) to meet consumer demands in Colombia and Brazil (da Silva 2008; da Silva and Martin 2007; IWC 2007). This hunt is considered a considerable threat since it is estimated that 600 botos are taken annually in the area surrounding the Mamirauá Sustainable Development Reserve alone (Serrano et al. 2007). In addition to the killings occurring for the piracatingafishery, evidence suggests that fishers kill botos intentionally because they regard them as competitors and because botos cause damage to fishing nets (Loch et al. 2009). Furthermore, botos and tucuxi, like other small cetaceans, are vulnerable to entanglement in fishing gear. Although incidental mortality has not been studied in most areas in the Amazon, a few studies show that lampara seine nets and gillnets pose significant threats (Best and da Silva 1993; Martin et al. 2004). Specifically, lampara seine is the most lethal type of net for botos (accounting for over 80% of related deaths), and drifting and fixed gill nets are responsible for most tucuxi mortalities (38.3% and 35.3% respectively) (Best and da Silva 1993). In light of these eminent threats, it is vital to determine if and how PAs can be an effective tool for the conservation of freshwater dolphins. For my Ph.D. dissertation I will evaluate if and how the Mamirauá Sustainable

2 Development Reserve in the Western Brazilian Amazon is providing ecological and conservation benefits to the two Amazonian river dolphin species. I will determine home range size and analyze movement patterns of river dolphins in MSDR, determine if MSDR is influencing fisher attitudes and conservation friendly behavior, and construct a population model to evaluate different reserve scenarios. The overall goal of my study is to investigate and highlight the reserve design elements vital for the establishment of effective freshwater dolphin protected areas. Study Site My study will take place in the Mamirauá Sustainable Development Reserve (MSDR), an IUCN Category VI protected area located in the North Western Brazilian Amazon between the junction of the Solimões and Japurá rivers. The 1,000,000 hectare reserve is comprised mostly of flooded forest, or várzea, which is considered critical habitat for many species (SCM 1996, Koziell and Inoue 2006). This protected area provides a unique opportunity to conduct my analysis for the following reasons. First, I will be working in collaboration with Projeto Boto, a research program under the Instituto Nacional de Pesquisas da Amazônia (INPA) that has been active in the focal area of MSDR since 1993 and has collected data related to the life history, behavior, ecology, physiology and movements of boto and tucuxi since its inception (IUCN 2000). A detailed description of Projeto Boto data collection methods is available in IUCN Among important findings relevant to my research, Projeto Boto has shown that dolphin distribution in MSDR is highly dependent on seasonal variation in water levels (Martin and da Silva 2004b). During the dry season, botos are concentrated in the main rivers and channels, whereas during the flooded season they enter MSDR (da Silva 2008, Martin and da Silva 2004b). Spatial segregation occurs in this population during the flooded season, with a higher proportion of adult males occurring in the main rivers compared to the innermost parts of MSDR, where the highest proportion of females and calves are found (da Silva 2008). Furthermore, Projeto Boto has identified a resident population of botos in MSDR made up of individuals that are present in the reserve for at least seven of 12 months of the year (Martin and da Silva 2004a). Second, PAs have long been criticized for excluding the human inhabitants that depend on the natural resources contained within their boundaries. In the past twenty years, however, particularly in Latin America, there has been an increasing trend to resolve this issue by developing protected area models in which human residents and their needs are incorporated into management plans. MSDR is considered one of the pioneers of this movement and was created with the aim of combining biodiversity conservation and sustainable resource use with the active participation of local human residents (Koziell and Inoue 2006; SCM 1996). The Mamirauá sustainable use model allows me to conduct some interesting research comparisons (see Objective 2) that would not be possible under a more traditional protected area model. Results of my study will provide new insight on if and how cetacean conservation can successfully occur in human inhabited PAs. Objectives and Study Design Below I provide a description of the two objectives of my dissertation that the Marine Mammal Society Grant would help fund. The funds would be used for the field expedition scheduled for October-November 2011 when I will complete work associated with Objectives 1 and 2.

3 Objective 1- Determine home range size and analyze movement patterns of I. geoffrensis. Determining home range extent can provide insight on how large a protected area should be and what habitat types it should include in order to provide protection for a species (e.g. Wilson et al. 2006). Through Projeto Boto, I currently have opportunistic sighting data for approximately 500 individually identified dolphins. To compliment this data, I will conduct a descriptive satellite telemetry study and track I. geoffrensis individuals using a satellite tag that will be placed on individuals during Projeto Botocapture expeditions (I plan to use a tag similar to the Mk10- AFB Transmitting Fast-GPS tag sold by Wildlife Computers that is currently in development). I will conduct a trial in October-November 2011 to determine the suitability of the proposed tag and identify necessary improvements. In the capture expedition anticipated for October-November 2012, I will follow up with deployment of at least five tags. I will determine home range extent using both Projeto Boto sighting data and the telemetry data. I will use Home Range Tools (HRT) for ArcGIS to run two home range analysis models: minimum convex polygon (MCP) and adaptive kernel (ADK). I will use the 95% ADK as a measure of a dolphin s home-range size and will use the 50% ADK to identify the core use areas (as recommended by Bertrand et al. 1996) I will overlay both the 95% and 50% ADK ranges with a polygon of MSDR to determine the area of overlap. Furthermore, I will overlay individual polygons to determine home range hubs (Gubbins 2002; Rayment 2009). Finally, I will use the Mann- Whitney U test to examine the difference between home range sizes of botos in the dry vs. flooded season, females vs. males, and residents vs. non-residents. In addition to home range analyses, I will use the HRT Display Travel tool to calculate average distance moved between fixes, average elapsed time between fixes, speed of movement, and total distance moved from the satellite telemetry data. Based on previous evidence that shows botos move out of the floodplain in the dry season to avoid being isolated in small lakes and channels (Martin and da Silva 2004a), I expect that MSDR is large enough to encompass the home range of resident dolphins during the flooded season, but not large enough to include the entire home range of these dolphins during the dry season. Furthermore, in agreement with predictions made by Martin and da Silva 2004b, I hypothesize that non-resident botos will have a significantly larger home range than resident botos and will swim from Mamirauáto other distant floodplain habitats; hence, protected areas like Mamirauá may offer little protection to transient dolphins. Moreover, if this prediction of transient dolphin movement is correct, the inclusion of floodplains as critical habitat will be essential in the development of future protected areas and protected area networks. Objective 2 Conduct an assessment of fisher attitudes and conservation behaviors towards river dolphins in and surrounding MSDR. Currently, the main threats to Amazonian river dolphins are entanglement in fishing gear and direct exploitation for use as bait in the piracatinga fishery (da Silva and Martin 2007; IWC 2007). Hence, the success of protected areas in terms of river dolphin conservation lies heavily in their effectiveness to decrease these threats. I will conduct a questionnaire survey in communities in and surrounding MSDR to determine if and how the reserve is alleviating these threats by influencing fisher attitudes and behaviors towards river dolphins. I will administer the survey in approximately 30 fishing communities (a random sample will be chosen from communities in which fishing is the main source of income). Communities will be divided into three categories:

4 focal area communities (communities located within the focal area of MSDR), subsidiary area communities (communities located within the subsidiary area of MSDR), and reserve-user communities (communities located near the reserve that have access to reserve resources but are not located within reserve boundaries). Where possible, the president of the community and 2-5 fishermen will be asked to complete the survey in each community. The main goal of the survey will be to determine the following: 1) frequency and nature of fisherydolphin interactions, 2) mortality of dolphins attributed to the community, 3) fisher attitudes towards I. geoffrensis and S. fluviatilis, 4) if and how conservation attitudes have changed since the inception of the reserve, 5) conservation behaviors exhibited by fishers, 6) and reasons for these conservation behaviors. I will use the software R to conduct a Discriminant Function Analysis and quantitatively determine if the three different types of communities are significantly different from each other based on the categorical responses provided in close-ended questions. I will conduct preliminary surveys in October-November 2011 and follow up with the adjusted final surveys in May-June 2012 and October-November 2012 to correspond with peak fishing season and varying water levels. I expect dolphin mortality rates will be greater in reserve-user communities than in subsidiary and focal area communities due to differences in enforcement effort. I also predict fishers living in subsidiary or focal area communities will exhibit more conservation friendly behaviors towards dolphins than fishers in reserve-user communities. Synthesis and Significance I will integrate the results of the objectives described above in a spatially explicit population model to evaluate the impact of various reserve scenarios on I. geoffrensis (Objective 3). With completion of this final objective, I will be able to describe Mamirauá s effectiveness in protecting river dolphins, describe the role PAs can play in river dolphin conservation, and provide corresponding management and reserve design suggestions. I will share my report with numerous government and non-government organizations including the Mamirauá Sustainable Development Institute, INPA and the South American River Dolphin Protected Area Network. I also hope to return to at least five of the communities I interview to share my results with the fishers. It is my hope that further understanding of riverine top predators by scientists, managers, and local residents will lead to an increase in conservation efforts directed at Amazonian aquatic mammals and their freshwater habitats. PROJECT TIMELINE 2011 July-September Model Building (Obj. 3) October-November Fisher Surveys (Obj. 2), Tag Trial (Obj. 1) 2012 January-February Analysis/Writing (Obj. 1 2,3)

5 May-June Fisher Surveys (Obj. 2) July-September Analysis/Writing (Obj. 1,2,3) October-November Fisher Surveys (Obj. 2), Tag Deployment (Obj. 1) 2013 January-August Analysis/Writing (Obj. 1,2,3) 2011 PROJECT BUDGET International Airfare $1,000 In-country Transportation $600 Lodging $200 Meals $100 Visa/Permit fees* $80 Field Notebooks $50 Boat Fuel (for travel between communities) $900 Boat Driver Compensation (for travel between communities) $500 Miscellaneous $70 Total Field Research Budget $3,500 Amount Received from Other Sources** $2,000 Amount Requested from Marine Mammal Society $1,500 * Projeto Boto has the necessary permits needed to capture and handle dolphins in Brazil. I am in the process of applying to the Conselho de Etica di INPA to obtain the permit needed to conduct the fisher surveys. I am also in the process of obtaining approval for my project from the University of Florida Institutional Review Board (Behavioral/NonMedical IRB-02) and University of Florida Institution Animal Care and Use Committee.

6 ** I was awarded a Tropical Conservation and Development Program Field Research Grant from the University of Florida Center for Latin American Studies on April 4, LITERATURE CITED Barlow J Management. In: Perrin WF, Wursig B, Thewissen JGM (eds). Encyclopedia of Marine Mammals, Academic Press: San Diego, USA; Best RC, da Silva VMF Inia geoffrensis. Mammalian Species, 426, 1-8. Da Silva VMF Amazon River Dolphin (Inia geoffrensis). P In: Perrin WF, Wursig B and Thewissen JGM (eds). Encyclopedia of Marine Mammals (2nd Edition). New York: Academic Press. Da Silva VMF, Martin AR Impact of human activities upon two species of dolphins in Amazonian flooded forest, Brazil. In: Abstracts of the 17th biennial conference on the biology of marine mammals, Cape Town, South Africa, 29 November 3 December Hoyt E Marine Protected Areas for Whales, Dolphins, and Porpoises. London, UK: Earthscan. IUCN C., T. Kasuya, R. R. Reeves, and B. D. Smith. - Biology and conservation of freshwater cetaceans in Asia. Y Occasional papers of the IUCN Species Survival Commission ; no. 23.: IWC Report of the sub-committee on small cetaceans. In: IWC Scientific Committee Annual Meeting. Available at Koziell I, Inoue C Mamirau Sustainable Development Reserve, Brazil: Lessons Learnt in Integrating Conservation with Poverty Reduction. IIED. 75 pg. Loch C, Marmontel M, Simoes-Lopes PC Conflicts with fisheries and intentional killing of freshwater dolphins (Cetacea: Odontoceti) in the Western Brazilian Amazon. Biodiversity and Conservation 18(14): Martin AR, Da Silva VMF. 2004a. Number, seasonal movements, and residency characteristics of river dolphins in an Amazonian floodplain lake system. Canadian Journal of Zoology 82(8): Martin AR, Da Silva VMF. 2004b. River dolphins and flooded forest: seasonal habitat use and sexual segregation of botos (Inia geoffrensis) in an extreme cetacean environment. Journal of Zoology 263(3): Serrano DB, da Silva VMF, Martin AR Illegal hunting causes the depletion of Amazon River dolphins (Inia geoffrensis) in Brazil. In: Abstracts of the 17th biennial conference on the biology of marine mammals, Cape Town, South Africa, 29 November 3 December 2007