Resource Assessments for Multi-Species Fisheries In

CM 2007/O:11 Resource assessments for multi-species fisheries in NSW, Australia: qualitative status determination using life history characteristics, empirical indicators and expert review. James Scandol and Kevin Rowling Wild Fisheries Program; Systems Research Branch Division of Science and Research; NSW Department of Primary Industries Cronulla Fisheries Centre; PO Box 21, Cronulla NSW 2230 Not to be cited without prior reference to the authors Abstract As the scope of fisheries management continues to broaden, there is increased pressure on scientific assessment processes to consider a greater number of species. This expanded list of species will inevitably include those with a range of life-history strategies, heterogeneous sources of information, and diverse stakeholder values. When faced with this challenge in New South Wales (Australia), the Department of Primary Industries developed systems and processes that scaled efficiently as the number of species requiring consideration increased. The key aspects of our approach are: • A qualitative determination of exploitation status based upon expert review. The current categories are: growth/recruitment overfished, fully fished, moderately fished, lightly fished, undefined and uncertain. • Application of management rules that require a Species Recovery Program should any species be determined to be overfished. • An emphasis on readily calculated empirical indicators (such as catch, catch-rates, length and age composition), rather than model-based estimates of biomass or fishing mortality. • Use of databases and electronic reporting systems to calculate empirical indicators based upon specified rules. Currently, there are 90 species considered with around six scientific and technical staff. These species were identified by commercial fishers as the important species from five multi-species and multi- method input-controlled fisheries. Many of these species are currently determined to be ‘undefined’. Performance indicators have been specified that promote a re-allocation of resources to improve our understanding of the status of the full range of species. Keywords: multi-species; empirical indicators; expert judgment; data-limited fisheries; Contact author: James Scandol: NSW Department of Primary Industries, PO Box 21, Cronulla, NSW 2230, Australia [tel: + 612 9527 8540, fax: + 612 9527 8576, e-mail: [email protected]]. 1 CM 2007/O:11 1 Introduction International developments in fisheries management have emphasised the importance of formal systems of performance monitoring based upon indicators and reference points (Caddy and Mahon 1995; Rosenberg and Repestro 1996). Many of these proposals have been based upon large single- species fisheries with significant stock assessment programs which enable quantification of the biomass of the spawning stock. Less attention has been paid to small multi-species fisheries with significant recreational harvests, or what has become known in the fisheries parlance as ‘data-limited’ fisheries (Kruse et al. 2005). Performance monitoring of such fisheries is, however, just as important for effective and accountable fisheries management, but new approaches need to be developed to deal with the very different circumstances presented by these ‘data-limited’ fisheries. The fisheries considered in this paper are those operating off coastal NSW, Australia. There are five input-controlled multi-species commercial fisheries, two quota-managed single species fisheries for blacklip abalone (Worthington et al. 1998) and eastern rock lobster (Liggins et al. 2000), and a large recreational fishery with around one million participants (Henry and Lyle 2003). The quota-managed fisheries for abalone and rock lobster have conventional model-based assessment programs and are not considered further here. To apply the approach used for these two species would be difficult and expensive to implement for other harvested species in NSW - many of which are caught in very small quantities relative to other fisheries in Australia and overseas. For these species, simpler and more cost-effective approaches are required to monitor the performance of the fishery management systems with respect to the biological sustainability of harvested fish populations. Performance management is required by law in NSW, with s7E(e) of the Fisheries Management Act (FMA) (1994) stating that a Fishery Management Strategy or Management Plan must ‘include performance indicators to monitor whether the objectives of the strategy (and the management plan) and ecologically sustainable development are being attained’. This commitment to performance monitoring extends to all of the goals/objectives of the fishery including the conservation of biological diversity and threatened species, commercial viability, cost-effective management and compliance and improving knowledge (e.g. NSW Fisheries 2003). The goal at the focus of this paper is to: ‘Maintain fish populations harvested by the [Fishery] at biologically sustainable levels’ (NSW Fisheries 2003 – Goal 2). This paper describes the approach developed by the NSW Department of Primary Industries (DPI) to undertake this task1. Note that determining, and then acting upon, the status of harvested fish populations has proved to be particularly challenging (Walters and Maguire 1996; Schnute and Richards 2001). Furthermore, most of the internationally accepted approaches to this problem have been designed for commercial fisheries several orders of magnitude more productive than those in NSW. An alternative approach was required. 1 This manuscript is a revised version of the paper developed to describe the assessment approach used by NSW DPI (Wild Fisheries Research Program, 2006. Determining the Biological Sustainability of Wild Fisheries in NSW: Concepts and Definitions. Cronulla, NSW DPI, 27pp). 2 CM 2007/O:11 2 Assessment of Wild Harvest Fisheries in NSW 2.1 Background Provisions within both State2 and Commonwealth3 law require environmental assessment of commercial fisheries in NSW (Scandol et al. 2005). Amongst many other outcomes, this process has identified the species harvested by each commercial fishery in NSW. These species divided into three categories: (1) highly important to the fishery (primary or target species); (2) of intermediate importance to the fishery (key secondary, byproduct or conditional target species); (3) species landed by the fishery in small quantities and of minor commercial value (secondary species). Species in categories (1) and (2), (hereafter referred to as ‘key species’) were also subject to a detailed risk assessment, where the risks to a species by the current and proposed operation of the fishery were evaluated (Astles et al. 2006). The environmental assessments of the commercial fisheries are very significant documents and extend to many hundreds of pages. Readers should refer to the Environmental Impact Statements4 should they require more information. One of the commitments from the environmental assessment process was the development of a ‘Stock Assessment Process’ for NSW (p 110, NSW Fisheries 2003). The primary objective of this process was to develop a practical mechanism for assessing the status of stocks of the key species. Although there is the potential for fisheries to cause an environmental impact to secondary species, it was recognized that fishery-oriented stock-assessment of such species was not possible and that other programs (such as fishery independent surveys or onboard observer programs) were more relevant managerial responses. In recognition that the resulting assessments of key species would not be a ‘stock assessment’ in the usual sense, the term ‘resource assessment’ is used hereafter. The principal outcome from such resource assessments must be, amongst other things, an identification of the species that require managerial attention. Usually this attention will be in the form of policy or regulatory changes that will promote improved yields and/or result in a reduction to fishing mortality. On the other hand, there are many species for which the current harvesting regime appears to be biologically sustainable, and this should be acknowledged by scientists, managers, stakeholders and the general public. The assessment of all of the key species in NSW is an extremely ambitious task. At present there are around 90 key species associated with the five input-controlled commercial fisheries in NSW5. As the taxonomic resolution of various groups of harvested species improves, this number will increase. A full description of the tasks included in the resource assessment and monitoring project is beyond the scope of this paper. Rather, the key aspects of this process will be described. 2 Environmental Planning and Assessment Act 1979; Fisheries Management Act 1994. 3 Environment Protection and Biodiversity Conservation Act 1999. 4 Available from www.fisheries.nsw.gov.au/commercial/management-strategies. 5 A current list of key species and their designation within each of the five main commercial fisheries is given in Appendix A. 3 CM 2007/O:11 2.2 Qualitative Determination of Exploitation Status Based Upon Expert Review Table 1 summarizes the characteristics associated with fish populations that are used to determine exploitation status of each key species. These determinations are made at an annual Resource Assessment Workshop and reviewed at the Catch and Effort Working Group (described below). Fisheries researchers generally define two types of overfishing: recruitment overfishing

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