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13.45 - 14.00 POSSINGHAM, HUGH P., Henrik Andren, and Anna Danell. The Ecology Centre, University of Queensland, Brisbane, QLD 4072, Australia, <hpossingham@zen.uq.edu.au> (HPP), Grimso Wildlife Research Station, Swedish University of Agricultural Sciences, SE-73091, Riddarhyttan, Sweden (HA, AD. ACTIVE ADAPTIVE MONITORING OF WILDLIFE FOR CONSERVATION, CONTROL AND HARVESTING? How much should wildlife managers spend on monitoring? For many species of wildlife, like the lynx, managers want to maintain viable populations. However if numbers are too high they are considered a pest. For species like this there are thresholds above and below which we do not want the population to pass. To maintain the population within an acceptable range managers use a harvesting strategy, e.g. remove 20% of the estimated population if the population is too high. This strategy relies on estimates of population size. More accurate estimates of population size cost more money, while crude monitoring is cheap but leads to more uncertainty about abundance. We use Markov decision theory to choose between three monitoring strategies where our objective is to minimise the chance a lynx population passes an upper or lower abundance threshold. We show that there is no single best monitoring strategy, it will depend on the current state of the population which varies. The relative economic costs of monitoring and exceeding either population threshold are found to be critical in determining the optimal monitoring strategy. This leads us to propose the new concept of state-dependent monitoring. 14.00 - 14.15 JONZÉN, NICLAS, Per Lundberg. Department of Theoretical Ecology, Ecology Building, Lund University, SE-223 62 Lund, Sweden. niclas.jonzen@teorekol.lu.se; INCORPORATING HABITAT SELECTION AND DISPERSAL WHEN MODELLING MARINE RESERVES In basic as well as applied ecology, we are trying to understand how organisms respond to patterns and processes. In the case of spatial control in fisheries and wildlife management, we want to know how spatial and temporal variability — including harvest — affect the distribution of the target species between protected reserves and exploited areas. Using habitat selection theory as the point of departure, I will show how habitat quality, dispersal, reserve size and harvest fraction determine the proportion of a habitat that should be protected from exploitation to achieve a given management or conservation goal. It turns out that if a population conforms to the ideal free distribution (IFD), the harvest rate resulting in the maximum sustainable yield is unaffected by the size as well as the quality of the reserve. Source-sink systems, where there is a net flow from "good" to "bad" habitats, complicate population management, and optimal harvesting decisions are contingent on dispersal rates and quality differences among habitats. I will conclude by suggesting that future work should try to bridge the gap between sound ecological theory — such as habitat selection theory — and operational models intended for guiding decision making. 14.15 - 14.30 ROBERTS, CALLUM M., James A. Bohnsack, Fiona Gell, Julie P. Hawkins, Renata Goodridge. Environment Dept, University of York, York, YO10 5DD, UK. cr10@york.ac.uk (CMR, FG & JPH); Southeast Fisheries Science Center, NOAA Fisheries, 75 Virginia Beach Drive, Miami, Florida 33149, USA (JAB), Dept of Marine Resource and Environmental Management, Faculty of Natural Science, University of the West Indies, Cave Hill, Barbados (RG). EVIDENCE FOR THE EFFECTIVENESS OF MARINE RESERVES, AND THEIR USEFULNESS IN MULTI-SPECIES SYSTEMS Marine reserves have been widely promoted as conservation and fishery management tools. There are robust demonstrations of conservation benefits, but fishery benefits remain controversial. However, there are now robust demonstrations that marine reserves in Florida (USA), the Gulf of Maine and St. Lucia have enhanced adjacent fisheries. Within five years of creation, a network of five small reserves in St. Lucia increased adjacent catches of artisanal fishers by between 46 and 90%, depending on gear type. In Florida, reserve zones in the Merritt Island National Wildlife Refuge have supplied increasing numbers of world record sized fish to adjacent recreational fisheries since the 1970s. On Georges Bank, large closed areas have turned around declining ground fish stocks and rehabilitated the scallop fishery. This evidence confirms theoretical predictions that marine reserves can play a key role in supporting fisheries, and shows they can work across a wide range of scales, species, habitats and fisheries. 14.30 - 14.45 PERES, CARLOS. Center for Ecology, Evolution and Conservation, University of East Anglia, Norwich NR4 7TJ, UK <C.Peres@uea.ac.uk> SPATIAL HETEROGENEITY IN GAME VERTEBRATE BIOMASS AND BUSHMEAT HUNTING PATTERNS IN AMAZONIAN FORESTS Tropical forest productivity is an important determinant of the baseline density of vertebrate populations but these bottom-up effects remain poorly understood. This will affect the population biomass of game stocks available to subsistence hunters and the probability of a stock being overharvested within a catchment area. Here I report on a 15-year program of line-transect surveys of Amazonian forest wildlife and examine the variation in catchment areas required if we were to maintain a sustainable harvest of different target species. When local hunting pressure was controlled for, forest type had a profound effect of the structure and aggregate biomass of vertebrate assemblages. This analysis is then informed by a comprehensive compilation of village-level bushmeat offtake studies across Neotropical forests. I examine how village traits affect the per capita harvest rates of different species and which species are most sensitive to hunting. In low-productivity forests, village density and the ratio between sink and source areas can often cross a threshold beyond which hunting is no longer sustainable for the most vulnerable game species. This approach can be used to design the spatial structure of hunting activities across large forest areas in order to retain viable large vertebrate populations at the scale of entire landscapes. 14.45 - 15.00 ROBLES ALEJANDRO and Maria de los Angeles Carvajal, Conservation International, 1919 M Street, NW, Suite 600, Washington D.C, 20036 USA (a.robles@conservation .org) TOWARDS INTEGRATED CONSERVATION IN THE GULF OF CALIFORNIA The Gulf’s high biodiversity and biological productivity make it a world’s priority ecosystems for conservation. The status of its biodiversity is the result of the economic activities. Nearly 50 percent of the nation’s fisheries production is generated there. The country’s most important shrimp culture and agriculture are in its coastal plains, causing ecosystem deterioration. Decreasing freshwater flows, pollution by agrochemicals and urban waste, sedimentation. Mangroves are being lost due to sedimentation, eutrophycation, and changes in water flows caused. The alteration of the physical and biological process has resulted in the near extinction of several species. Governmental and non-governmental conservation initiatives have been undertaken. As a result of this efforts, ten natural protected areas, adding to 27,334 sq. km. have been established. Of these, 8,207 sq. km. are marine protected areas, which represent 3.2 percent of the total sea surface. Six terrestrial add up to 19,127 sq. km, including 3,308 sq.km of the Gulf’s islands. Thus, terrestrial NPA cover 4.8 percent of its terrestrial area. The capacity to manage these protected areas has improved due to increase federal government intervention and increased support from NGOs, the construction of alliances and coalitions have been crucial on moving forward the conservation agenda. 15.30 - 15.45 Silva, José Maria Cardoso, Luis Paulo Pinto, Roberto Brandão Cavalcanti, CECILIA KIERULFF. Conservation International do Brasil, Av. Nazaré 541/310, 66035-170, Belém, Pará, Brazil, <j.silva@conservation.org.br> (JMCS). Conservation International do Brasil, Av. Getúlio Vargas 1300/7o andar, 30112-021, Belo Horizonte, MG, Brazil (LPP). Conservation International do Brasil, SCLN 212, Bloco D, Sala 103, Asa Norte, 70864-540, Brasília, Distrito Federal, Brazil & Departamento de Zoologia, Universidade de Brasília, Brazil (RBC). ESTABLISHING BIODIVERSITY CORRIDORS IN THE BRAZILIAN ATLANTIC FOREST The Atlantic Forest, one of the world's top five terrestrial biodiversity hotspots with an extraordinary concentration of endangered and endemic taxa, has substantial heterogeneity in species distributions. There are at least seven major biogeographic subunits: Brejos, Pernambuco, Bahia, Diamantina, São Francisco, Interior Forests, Serra do Mar and Araucária. The Serra do Mar subunit is the best conserved, with approximately 30% of the natural forests remaining and a comprehensive system of protected areas. All other regions lost most of their forests and the current forest remnants are poorly protected. Two large-scale biodiversity corridors in the Atlantic Forest form regional planning units to direct the creation of protected areas in key sites and designate areas of forest restoration across the landscape to effectively connect existing forest patches. Corridor design maximizes the potential of species protection in a workable political and economic context. However, this strategy requires a strong commitment of local institutions with technical capacity to orient and develop conservation actions, multidisciplinary and innovative research, political support from local communities and long-term financial support. 15.45 - 16.00 EARLE, S. Conservation International, 1919 M Street N.W., Suite 600, Washington, DC 20036, USA Earle, Sylvia A. Conservation International and National Geographic Society. Mailing address: DOER, 12812 Skyline Blvd., Oakland, CA 94619 USA, (saearle@aol.com). STRATEGIES FOR A SEA CHANGE IN MARINE CONSERVATION Dr. E.O. Wilson has observed that over the ages, mankind has relentlessly eliminated "the large, the slow and the tasty" creatures of the land. Likewise in the sea, humans as predators are profoundly altering the abundance and diversity of wildlife. Unprecedented habitat destruction by commercial fishing gear and greatly increased levels of capture and consumption of marine organisms in recent decades have resulted in swift and sharp population declines in numerous marine species. New polices are aimed at reversing the trend with emphasis on establishing large, fully protected areas in the sea that parallel terrestrial parks. Since much of the ocean is beyond national jurisdiction and many heavily exploited marine species are highly migratory, international agreements are necessary. For ocean wildlife, the 20th Century was marked by greater learning and greater losses than any previous time in history. The 21st offers opportunities to develop a new ethic beneficial to the future of the ocean and of mankind. 16.00 - 16.15 BAKARR, MOHAMED I. Center for Applied Biodiversity Science at Conservation International, 1919 M Street N.W., Suite 600, Washington, DC 20036, USA. <m.bakarr@conservation.org> THE BUSHMEAT POLICY PROBLEM AND APPROACHES TO ADDRESSING IT - LESSONS FROM WEST AFRICA The challenge of addressing bushmeat hunting in tropical rain forests requires a policy strategy that is guided by good science. Unlike marine ecosystems where much progress has been made in this regard to enhance biodiversity conservation efforts, science has yet to make any significant impact on addressing bushmeat hunting in tropical terrestrial ecosystems. For many severely impacted species (e.g. large mammals), conservation efforts has hitherto relied on public attention and support to address threats despite the considerable research effort that has gone into understanding species population dynamics in relation to hunting pressures in tropical rain forests. In this paper, I discuss the implications of this apparent disconnect between science and policy using non-human primates in West Africa as a case study. Despite a fairly good knowledge of their ecology and distribution through the region, non-human primate populations in West Africa remain increasingly threatened by bushmeat hunting. Solutions will need to be implemented within the broader landscape approach that promotes integration of science and policy for the benefits of both humans and wildlife. 16.15 - 17.30 Plenary Discussion |