SY8.1 08:30 Empirical advances in understanding larval connectivity in marine populations. Williamson, DH *, ARC Centre of Excellence for Coral Reef Studies. James Cook University, Townsville, Qld. Australia; Almanny, GR ARC Centre of Excellence for Coral Reef Studies. James Cook University, Townsville, Qld. Australia. & Centre National de la Recherche Scientifique (National Center for Scientific Research), Criobe, France ; Berumen, ML Red Sea Research Center, King Abdullah University of Science and Technology, 23955-6900 Thuwal, Kingdom of Saudi Arabia; Harrison, HB ARC Centre of Excellence for Coral Reef Studies. James Cook University, Townsville, Qld. Australia; Planes, S Centre de Recherches Insulaires et Observatoire de lâ€™Environnement, BP 1013, 98729 MoorĂ©a, French Polynesia; Saenz-Agudelo, P Red Sea Research Center, King Abdullah University of Science and Technology, 23955-6900 Thuwal, Kingdom of Saudi Arabia; Thorrold, SR Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA; Jones, GP , ARC Centre of Excellence for Coral Reef Studies & School of Marine and Tropical Biology. James Cook University, Townsville, Qld. Australia; |
Abstract: Populations of most marine fishes and invertebrates are connected through larval dispersal. Determining the scales of larval connectivity is integral to understanding how populations persist, how vulnerable they are to exploitation and habitat loss, and to the effective application of no-take marine reserve networks. In recent decades, several techniques have been applied for in-situ tracking of larval dispersal. Population genetics, otolith microchemistry and bio-physical modeling provide connectivity information over relatively broad spatial and temporal scales, while trans-generational larval tagging and genetic parentage analyses provide high resolution connectivity data at more localised scales. Here we discuss the various techniques that have been used to quantify larval connectivity in marine ecosystems and draw upon recent case studies from Papua New Guinea and Australia. Findings demonstrate that the majority of coral reef fish larvae disperse over relatively short distances (10â€™s of km), that levels of larval retention (self-recruitment) are surprisingly high, and that a small proportion of larvae can disperse longer distances (beyond 100 km). There is a high level of congruence in dispersal distances between fish species with markedly different life history traits and pelagic larval durations. A common finding from these studies is that local management actions can provide local benefits for both population persistence and fishery sustainability.
SY8.2 08:45 Realized patterns of larval dispersal and the design of marine reserve networks in the Philippines. Abesamis, RA *, Silliman University-Angelo King Center for Research and Environmental Management; Saenz-Agudelo, P King Abdullah University of Science and Technology; Bernardo, LPC Tokyo Institute of Technology; Berumen, ML King Abdullah University of Science and Technology; Jadloc, CRL Silliman University-Angelo King Center for Research and Environmental Management; Villanoy, CL University of the Philippines-Marine Science Institute; Alcala, AC Silliman University-Angelo King Center for Research and Environmental Management; Russ, GR , James Cook University; |
Abstract: The spatial scale and dynamics of larval dispersal within ecological time scales are critical considerations in designing effective networks of no-take marine reserves. However, empirical studies of larval dispersal in relation to real-world reserves and prevailing hydrodynamic regimes are rare, limiting our understanding of how reserve networks can achieve conservation objectives in different socio-ecological settings. We applied genetic parentage analysis on a coral reef fish (Chaetodon vagabundus) to determine patterns of larval dispersal amongst community-based reserves and fishing grounds in the Philippines. We found that larval dispersal was usually less than 20 km (mean = 18.6 Â± 10.8 (SD) km; mode = 8.0-10.0 km; range = 3.0 to 39.5 km) despite the relatively long pelagic larval life of the model species (3 to 6 weeks). These single-generation larval dispersal events frequently connected reserves to fellow reserves and fished areas, indicating that population enhancement will occur not very far from natal reserves (within 10â€™s of km). Seasonal trends in the direction of larval dispersal appear to be strongly driven by reversing monsoon winds, suggesting that larvae exported by reserves will be distributed more evenly. These findings have direct implications for the minimum size of reserves, the maximum spacing between reserves and the spatial scale of inter-institutional governance of reserve networks in the Philippines and other countries in the Coral Triangle.
SY8.3 09:00 Planning marine protected area networks for both feature representation and connectivity. Bode, M *, University of Melbourne; Pressey, R James Cook University; Weeks, R James Cook University; Williamson, D James Cook University; Jones, G James Cook University; Hopf, J James Cook University; |
Abstract: Modern systematic conservation planning (SCP) remains primarily focused on the representation of biodiversity features. However, ecological processes that are critical to the persistence of these features cannot currently be included. This is because (1) processes are poorly understood; and (2) SCP methods are insufficiently sophisticated. Planners must assume that representation guarantees persistence, or use methods biased towards reserve geometries that are believed better for persistence (e.g., low perimeter:area ratios). Principal among the processes not considered by SCP is persistence, within and without reserves. In marine ecosystems, persistence depends on species receiving larval recruitment that is sufficient to compensate for natural mortality within reserves; and also replace fishing mortality outside reserves. We have constructed a conceptually-straightforward and computationally-feasible method for designing reserve networks that meet both demographic and representation constraints. We apply this method to create a conservation plan for the Keppels Group in the Great Barrier Reef. Recent broadscale genetic parentage analyses for Plecropomus maculatus, a target species of local recreational fishers, allow dispersal kernels to be parameterised. The resulting reserve network efficiently ensures demographic persistence of the species across both protected and unprotected reefs, as well as representation targets for important biodiversity features.
SY8.4 09:15 Strategies in scheduling marine conservation plans in a networked system. Kininmonth,S.J. *, Stockholm University; Weeks, Rebecca James Cook University; Abesamis, Rene James Cook University; Berger, Maria University of Queensland; Treml,Eric University of Melbourne; Williamson, David James Cook University; Pressey, Robert James Cook University; Bodin,Ă–rjan , Stockholm University; |
Abstract: Instantaneous implementation of systematic conservation planning at a regional scale is rare. More typically, planned actions are applied over periods of years or decades. During protracted implementation the character of the connected ecological system will change as a function of external anthropogenic pressures, internal metapopulation processes, and environmental fluctuations. For heavily exploited systems, the quality of the marine habitat will deteriorate as the plan is being implemented and this could influence the schedule of management application necessary to achieve the conservation objective. Understanding the best strategy to adopt for applying management within a connected environment is desirable, especially given limited conservation resources. Here we modelled the sequential application of marine management to protect from direct anthropogenic pressures, within a metapopulation framework, using a range of network-based decision rules. Each rule was evaluated in the context of achieving the maximum population lifetime at the conclusion of the implementation phase. Model results highlighted the benefits of including network processes in conservation planning. We then considered this decision framework for a 34-year schedule of marine reserve establishment in the Philippines.
SY8.5 09:30 Towards better integration of seascape connectivity in marine conservation. Olds, AD *, University of the Sunshine Coast; Connolly, RM Griffith University; Pitt, KA Griffith University; Maxwell, PS Griffith University; Albert, S University of Queensland; |
Abstract: Connectivity is an important consideration in marine conservation because it provides the mechanism for reserves to sustain populations beyond their borders, and is critical for reversing existing environmental impacts. Few studies, however, have adopted a quantitative approach, like landscape ecology, to assess the value of connectivity in conservation. To illustrate this point, I discuss findings from our work in tropical and subtropical Pacific seascapes. We show that seascape connectivity enhanced marine reserve effectiveness across the western Pacific. This includes synergistic effects on productivity, diversity and ecological processes. To broaden the relevance of these results, we evaluated published seascape connectivity studies (197 studies) and identified those that examined effects on assemblages in reserves. Of the 38 papers that met these criteria, few considered potential interactions between reserve and seascape effects. All that did reported synergistic effects on fish abundance, diversity or ecological processes. In addition, >71% of studies that examined seascape effects in reserves, but not the interaction between factors, also reported positive effects on production, diversity and processes. By improving our understanding of seascape ecology and connectivity, and incorporating this field of research into conservation decision-making, we should therefore expect greater success in restoring exploited populations and the functioning of marine ecosystems.
SY8.6 09:45 Towards explicit objectives for connectivity in marine conservation planning. Weeks, R *, Australian Research Council Centre of Excellence for Coral Reef Studies; Pressey, RL Australian Research Council Centre of Excellence for Coral Reef Studies; |
Abstract: Systematic conservation planning requires quantitative objectives to link data on biodiversity pattern and process with potential locations of conservation areas. Connectivity processes such as larval dispersal are key to structuring coral reef fish populations, and the need to consider connectivity in designing networks of marine protected areas has been emphasised. However, in the context of conservation planning, connectivity is poorly defined, objectives fail to address the ultimate reasons for focusing on connectivity, and guidelines have provided broad â€śrules of thumbâ€ť rather than specific, quantitative recommendations. Recent empirical advances have increased the availability of spatially explicit, quantitative information on larval dispersal. These new data demand renewed efforts to specify quantitative conservation objectives. We outline the rationale for, and benefits and limitations of, different approaches to defining explicit connectivity objectives. These include patch-specific approaches, specifying minimum thresholds for larval recruitment to individual marine protected areas, and graph-theoretic approaches that prioritise sites based on network-wide metrics, such as larval sources or stepping-stones. Choice of approach will vary with connectivity-related goals, data availability, spatial scale of analysis, and planning goals. We conclude with suggestions for improving planning guidelines for areas without empirical connectivity data.
SY8.7 10:00 Analysing the (mis)fit between institutional and ecological networks of the Coral Triangle. Treml, EA *, Department of Zoology, University of Melbourne, Victoria, Australia; Bodin, Ă– Stockholm Resilience Centre, Stockholm, Sweden; Fidelman, P Sustainability Research Centre, University of the Sunshine Coast, Maroochydore Queensland, Australia; Kininmonth, S Stockholm Resilience Centre, Stockholm, Sweden; Ekstrom, J Natural Resources Defense Council, San Francisco, California, United States; |
Abstract: The marine resources of the Coral Triangle (CT) region of the Indo-West Pacific are some of the most biologically diverse in the world and sustain the livelihoods of a large and growing population. Sustainability of this biodiversity hotspot is largely dependent on maintaining ecological linkages among seascapes (i.e., dispersal/migration among sites), and minimizing local-to-regional threats through international policy and local governance. However, the governance structure within the region is highly complex forming a network of cross-institutional interactions at all levels. Here, we developed an approach for mapping institutional linkages related to marine resource management at international levels, and overlaid these networks with multi-species connectivity networks to discover where, and to what degree, the social-ecological system is in alignment. Our framework for visualizing and analysing the integrated ecological-institutional networks thereby identified important fit and misfit between the regionâ€™s ecology and governance. The analysis revealed that the CT region is aligned in terms of policies on marine protected areas, but much less alignment exists with respect to fisheries. In quantifying the fit and misfit across various marine management themes, we have identified important reefs and trans-national marine corridors which may lack adequate institutional arrangements and protection, leaving them areas at risk to local and international threats.