Integrating Fishers’ Knowledge with Survey Data to Understand the Structure, Ecology and Use of a Seascape off Southeastern Australia

Australia involves fishers at all stages of the fishery assessment and management process. A key factor in the success of this approach is using fishers’ information to supplement and interpret standard fisheries data. From 1994, we collected fishers’ information on fishing grounds and habitats as part of a 5-year study of a continental shelf fishery. We met regularly with experienced fishers during port visits, commercial fishing operations at sea and in formal (management) meetings. This pattern of liaison enabled us to build relationships and a level of trust that facilitated a two-way sharing of knowledge. We integrated the ecological knowledge of fishers with scientific survey data to map and understand the seascape (seabed landscape) in a way that would not have been possible from scientific data alone. Fishers provided detailed information on the fishery, navigation, fishing effort distribution, individual species, fish behaviour, productivity, seabed biology, geology, and oceanography. A key result was an interpreted seascape map incorporating geomorphological features and biological facies at a variety of spatial scales of resolution from 10s to 100s of km. Supported by industry, we are now extending the mapping project to the entire shelf and slope of the South East Fishery region. Fishers believe that the project provides them with the opportunity to contribute to developing spatial management under Australia’s ‘Oceans Policy’, and guarantees their involvement in a developing program of ‘regional marine planning’. However, they also fear that their information will be used against them especially for closing off valuable fishery areas. We discuss the importance of fishers’ knowledge to interpreting scientific data, and the need for an ongoing dialogue between the fishing industry, scientists and managers. Only this ongoing dialogue will ensure that fishers’ knowledge is used appropriately and, equally importantly, that fishers’ concerns are addressed in developing management options for this area. INTRODUCTION Management of the world’s oceans has typically been driven by single issues – for example, how many fish to catch, where to discard waste, where to mine, dredge, or drill for oil, and more recently which areas to protect (Allison et al. 1998; McNeill 1994). At its simplest, single-issue management can be achieved with specific and limited information and by ignoring many of the potential interactions with other issues or aspects of the marine environment. However, coincident with our increasing awareness of the ecosystem services provided by the marine environment (Norse 1993), is an increasing recognition of the limitations of single-issue management (Sainsbury et al. 1997), especially as our use of the oceans continues to increase. It is no longer sufficient to manage a fishery solely on the basis of the number of fish removed; instead, where and how fishing occurs, and with what impacts, have become equally important questions. To answer these questions requires first that we define the management units we are dealing with (Langton et al. 1995). In particular, and as has been the case on land for centuries, spatial attributes of the marine environment have become increasingly important for effective management. This requires that we understand the ecological patterns at regional and local scales, and integrate over these scales to provide a ‘seascape’ perspective (Garcia-Charton and Perez-Ruzafa 1999). Australia is developing integrated management of its marine resources through Australia’s Oceans Policy, launched in December 1998. Principal drivers for the policy are: ecosystembased management; integrated oceans planning and management for multiple use; promoting ecologically sustainable marine-based industries; and managing for uncertainty (Commonwealth of Australia 1998). It is recognized that real success of the plan will depend on all Australians gaining an appreciation and understanding of both the complexity of the ocean environment, and the interaction of humans within that environment (Sakell 2001). The marine environment off southeast Australia is the test case for ‘regional marine planning’ in Australia as it forms the first of 13 ‘large marine domains’ (LMDs) that will eventually be covered by management plans. While there are some spatial data relevant to fishery management available for this area, in general they are either of low resolution (e.g. the start and end positions of commercial fishing operations from fishery Page 239, Williams & Bax: Integrating Fishers’ Knowledge with Survey Data logbook records), or lack ecological interpretation (e.g. bathymetric and geological maps from geoscience sampling). Until recently, little was known about the spatial organization of habitats (substrata, biota and adjacent water column) or the ways in which the seabed is used as fishing grounds. Seabed habitat in the South East Fishery (SEF) was mapped for the first time as part of a five-year study to interpret the ecological processes contributing to the productivity of the shelf fishery ecosystem – ‘the ecosystem project’ (Bax and Williams 1999). The SEF is a complex, multi-species, multi-sector fishery (Tilzey and Rowling 2001) that operates in a large fraction of the South East LMD adjacent to mainland Australia. The mapped area was ~24,000 sq km of the continental shelf (~25-200 m depths) adjacent to the coastline between Wilsons Promontory in eastern Victoria and Green Cape in southern NSW – the southeastern point of the Australian continental margin where east and south coasts meet (Bax and Williams 2001: Fig. 1). In that study, survey data provided the means to determine the structure of the seabed and its association with biological communities and environmental factors at particular scales in space and time (Bax and Williams 2001; Williams and Bax 2001). The addition of fishers’ ecological knowledge aided the interpretation of those associations, as well as enabling an understanding of the ways in which the seabed is used by the commercial fishing fleet. As it turned out, fishers’ information was so useful that we developed a second study – ‘the mapping project’ – using fishers’ information on habitat types and distribution (interpreted through scientific knowledge and ground-truthing) as the primary data source to develop fine-scale maps of the southeast Australian seascape. In this paper, we first describe how fishers’ knowledge contributed to the ecosystem project and explain why this provided a better understanding than a study based on scientific survey data alone. Second, we provide an overview of our methodology for collecting and integrating fishers’ knowledge in the follow-up mapping project. Finally, we draw attention to the benefits of combining fishers’ ecological knowledge with scientific survey data to provide a seascape perspective of the marine environment, and stress that this combination requires an ongoing dialogue between the fishing industry, scientists and managers. The direct benefit of combining our knowledge in this way is an improved understanding of the seascape. An indirect benefit is that it empowers fishers with the opportunity to be actively involved in developing management options for the marine environment that they are most familiar with. THE SOUTH EAST FISHERY The continental shelf and slope off south-eastern Australia is the area of greatest fishing effort within the South East Fishery (SEF) – Australia's largest scalefish fishery, and the most important source of scalefish for domestic markets. Trawling started in the early 1900s, and by 1999 the SEF fleet was made up of 89 operating otterboard trawlers (draggers) and 20 Danish seiners (the ‘trawl sector’) (Tilzey and Rowling 2001), as well as a smaller number of demersal longliners, dropliners, mesh-netters and trappers (the ‘nontrawl sector’). More than 100 species form the commercial catch of the fishery, but 18 species or closely-related species-groups managed by a system of catch-quotas make up the bulk (> 80%). Annual total allowable catches of individual species range from a few hundred to a few thousand tonnes generating a total value for the fishery of about A$70 million. OVERVIEW OF THE ‘ECOSYSTEM’ AND ‘MAPPING’ PROJECTS The ecosystem project was designed to consider the ways in which management intervention, beyond the established single-species fisheries management, could have a direct effect on the long-term productivity of this fishery ecosystem (Bax et al. 1999). Production was taken to mean both the production of fish and the factors that determine their availability to the fishery, while our concept of “ecosystem management” was tied strongly to the notion of needing to manage peoples’ interactions with ecosystem components (Bax et al. 1999). Engagement with the fishing industry was desirable to understand how fishers viewed the ecosystem, how they interacted with it, and how to best target our limited survey time. Accordingly, we initiated a two-pronged industry liaison program when the project started. Depending on individual skills and experience, members of the project team became involved in formal fishery management and assessment meetings, and/ or spent time in the two big ports in our study area (Eden and Lakes Entrance) and did trips to sea on fishing boats (several trips in the first year, then only 1-2 per year). A particularly useful feature of our sampling program was using industry vessels for specialized fishing. Collectively, these interactions enabled us to establish contact with a range of industry personnel from the working skippers to the association executives. This gained us the support (and data) of individual operators and, in addition, the endorsement of the executive to further develop the project. Putting Fishers’ Knowledge to Work– Conference Proceedings, Page 240 We maintained fairly regular contact with a core group of operators and were able to build up a level of trust and dialogue with this core group as the project developed. Our findings were reported back to individuals and the peak industry associations on an ad-hoc basis during the course of the project. So, in summary, our approach to industry involvement evolved naturally during the ecosystem project – importantly, it lacked systematic planning or protocols, and there were no obvious benefits for industry. The contacts with industry members and associations that we developed during the ecosystem project proved crucial in garnishing support for the second project – the mapping project – that makes extensive use of industry information and has explicit benefits (and risks) for industry. In this partnership project, we are extending the seascape mapping to the entire continental shelf and upper slope (to ~ 1000 m depth) of the SEF region. In contrast to the ecosystem project, the mapping project has a planned methodology for collection, review and release of industry data. However, our approach is necessarily adaptive as the scale and detail of outputs are realized, and as industry responds to a rapidly evolving environmentally-focused fishery management regime. Key elements of the methodology are discussed in the final part of this paper. Value of fishers’ knowledge for navigating and mapping When we started the ecosystem project our means of navigating around the fishery seabed was limited to what could be gleaned from thirdparty, coarse-scale bathymetry data and navigation charts – primarily point-source depth soundings, the approximate positions of key depth contours including the continental shelf edge at ~ 200 m, and the positions of some nearsurface rocky banks identified as shipping hazards (Table 1). This information, in combination with some prior survey data and some rapid exploration by echosounding during survey, enabled us to fix a set of transects and sampling sites, stratified by depth and latitude (Bax and Williams 2001: Fig. 1). These were used for broad-scale coverage of the area during 4 seasonal trawl surveys – by definition on sediment substrata. But to meet the core aim of the project, which was to understand the importance of habitat to fisheries productivity, we needed to both survey a range of characteristic rocky reef habitats in the study area and understand the spatial context of habitats, e.g. patch sizes, boundary types and