This record describes, and links to a working paper produced through the Crawford School of Economics and Government at The Australian National University in Canberra. Using data from what was once one of the world's largest capture fisheries the economic value of a marine reserve is calculated using a stochastic optimal control model with a jump diffusion process. The results show that with a stochastic environment an optimal-sized marine reserve can generate a triple payoff that (a), raises the resource rent even when harvesting is 'optimal', (b) decreases the recovery time for the biomass to return to its former state and smooths fishers' harvests and resource rents, and (c), lowers the chance of a catastrophic collapse following a negative shock.

This record describes, and links to a working paper produced through the Crawford School of Economics and Government at The Australian National University in Canberra. We contribute to the understanding of marine reserves and the management of renewable resources with uncertainty. We show that the key benefit of reserves is that they increase resilience, or the speed it takes a population to return to a former state following a negative shock. Resilience can also increase resource rents even with optimal harvesting. We contradict the accepted wisdom that reserves have no value if harvesting is optimal, reserves and optimal output controls are equivalent, reserves have value only with overexploited populations and that reserves must be large to offer benefits to fishers.

This record describes, and links to a working paper produced through the Crawford School of Economics and Government at The Australian National University in Canberra. The paper analyses the economic payoffs from marine reserves using a stochastic optimal control model. The results show that even if the reserve and harvested populations face the same negative shocks, harvesting is optimal, the population is persistent and with no uncertainty over current stock size, a reserve can increase resource rents. Using actual fishery data we demonstrate that the payoffs from a reserve, and also optimum reserve size, increase the larger is the magnitude of the negative shock, the greater its frequency, and the larger its relative impact on the harvested population.

As management of marine living resource moves beyond simple single species resource utilisation concerns to ecosystem-based management, consideration of habitat dynamics is becoming an integral part of marine resource management. Previous studies have found that habitat can play a critical role in both single species and community level dynamics of species of commercial concern (Sainsbury, 1987; Sainsbury, 1988; Auster & Malatesta, 1995; Freese et al. 1999; Lindholm et al. 1999; Jackson et al. 2000; Sainsbury et al. 2000). Moreover, benthic habitat is becoming a conservation concern in its own right (Environment Protection and Biodiversity Conservation Act 1999). Useful first steps in understanding local benthic habitat dynamics is to collect observation (preferably through time) of the benthos and then to attempt to create dynamic models that capture the broadscale dynamics of the habitat of interest. Just such an exercise was undertaken for the major benthic habitat types in the North West Shelf of Australia (specifically epibenthic, mainly sponge, habitats, seagrass, macroalgae and mangroves). Between 1983 and 1997 photographic data on benthic habitats were collected on the North West Shelf of Australia by CSIRO Marine Research. These data were used to calculate proportional coverage of small (<25 cm) and large (>25 cm) epibenthos on the seabed between depths of 20 and 200 m. These observations and the fisheries effort data for the Taiwanese (1973 to 1981) and domestic fleets (1987 to 1997) were pooled onto a spatial grid of 10 by 10 nautical minutes with a temporal scale of a year. A multivariate analysis of the main factors associated with the distribution of the benthic habitats was undertaken (as a guide for factors to include in the final habitat dynamics model). The observations suggested that there was a strong depth-dependent gradient in the biomass and coverage of benthic habitat, which did not appear to be related to bottom stress, but may have been associated with sediment substrate properties. Given the importance of bottom stress in shaping benthic habitats in many other locations around Australia (Pitcher et al. 2002; Pitcher et al. 2004a; Pitcher et al. 2004b and Phillip England, CSIRO Marine and Atmospheric Research, pers. comm.) it is surprising that the analyses showed it to be a non-significant physical factor in determining proportional coverage on the North West Shelf (NWS). During the model development phase of the study a dynamic age-structured metapopulation model was created. This habitat model includes depth and substrate dependent recruitment, growth natural mortality and removal rates by fishing and cyclones. The parameters used in this model were either taken from literature or estimated by minimising the sum of squares between the observed and estimated proportional coverage. The model results easily reproduced the observed patterns of strongly depth related recruitment. It also showed that trawl fishing effort (both by Taiwanese and domestic fleets) was probably a significant factor in shaping the current distribution of benthic habitats on the NWS. There were issues with the models ability to predict recovery rates that match the empirical data. This is almost undoubtedly the result of poorly spatially resolved historical catch time series and a too coarse model resolution. Recasting future analyses and modelling efforts on finer (or more irregular) grids should go a long way to rectifying these issues. Nevertheless, even as is, the model still performs acceptably, particularly within an MSE framework. The bulk of the data (and subsequent modelling efforts) dealt with epibenthic (mainly sponge) habitats. The same model was also applied (in a more limited extent) to seagrass, macroalgae and mangroves. There was substantially less data available for these groups and the models were parameterised from the literature and expert knowledge.

This record describes, and links to a working paper produced through the Resource Management in Asia-Pacific (RMAP) Program based at The Australian National University in Canberra. The experience of the Fiji Locally Managed Marine Areas (FLMMA) network provides an illustration of how to mainstream community-based resource management practices that began with local communities, and were in-turn supported by a Government which has witnessed the success of community-based intervention. To improve the success of conservation in the communities and attract attention to its approach, FLMMA formed a learning portfolio. This is a network of projects that use a common strategy to achieve a common end and agree to work together to collect, test and communicate information about the conditions under which the strategy works, to enable the partners to exchange ideas and experiences. The learning portfolio enhances collaboration and also ensures that lessons learnt are shared widely with people in the network. FLMMA is working to increase the effectiveness of conservation and to ensure that the involvement of people in the management of their marine resources is both satisfying and meaningful. Modern science is an important part of the FLMMA approach because it is used to demonstrate the effects of the use of traditional resource management practices. Using simple biological, social, and economic monitoring methods, the villagers are collecting impressive results on resources and habitat recovery and the associated social and economic improvements in living conditions. The objectives of improving conservation to protect biodiversity and improve people's living conditions are important features of the kind of community-based resource conservation that is now being undertaken in the Pacific and Asia region. The objectives are also consistent with national policies for inshore fisheries development and global concerns about poverty alleviation. The success of community-based conservation in different parts of Fiji has resulted in long-term support from the communities. It has also facilitated the articulation of Government fisheries development policies. The Government has set up a new conservation unit and has formalised its support, and adopted the FLMMA method of involving local community units in the sustainable use of their marine resources. Under FLMMA, the success and combined experiences of conservation practitioners are being used to mainstream resource conservation and influence policy development in Fiji.