Linking risk factors to risk treatment in ecological risk assessment of marine biodiversity

ICES Journal of Marine Science ICES Journal of Marine Science (2015), 72(3), 1116– 1132. doi:10.1093/icesjms/fsu207 Contribution to the Themed Section: ‘Risk Assessment’ Food for Thought Linking risk factors to risk treatment in ecological risk assessment of marine biodiversity Department of Primary Industries, Fisheries NSW, PO Box 5106, Wollongong 2520, Australia *Corresponding author: tel: +61 2 4222 8344; fax: +61 2 4222 8338; e-mail: Astles, K. L. Linking risk factors to risk treatment in ecological risk assessment of marine biodiversity. – ICES Journal of Marine Science, 72: 1116 – 1132. Received 25 June 2014; revised 13 October 2014; accepted 26 October 2014; advance access publication 21 November 2014. Implementing marine ecosystem-based management at regional and small spatial scales is challenging due to the complexity of ecosystems, human activities, their interactions and multilayered governance. Ecological risk assessments (ERAs) of marine biodiversity are often used to prioirtise issues but only give broad guidance of how issues might be addressed in the form of strategies. However, at small and regional spatial scales marine natural resource managers have to make decisions within these strategies about how to manage specific interactions between human uses and ecological components. By using the transition between risk characterization and risk treatment in ERA for marine biodiversity tractable ways through the complexity can be found. This paper will argue that specific management and research actions relevant to smaller spatial scales can be developed by using the linkage between risk factors and risk treatment in ERA. Many risk factors require risk treatments that extend beyond the boundary of local agencies or sector responsibilities. The risk factor-treatment platform provides a practical way that these boundaries can be opened up by providing a scientifically based and transparent process to engage all actors who need to be involved in addressing the issues raised by an ERA. First, the principles of the mechanism will be described. Second, how the mechanism is constructed will be introduced using examples from an urban estuary. Application of the mechanism reveals three different types of risk factors (stressor, ecological, and knowledge gap) that can be used to develop specific management and research actions to treat risks. The systematic approach enables the dual complexities of marine ecosystems and multiple human pressures to be unravelled to identify and target issues effectively. The risk factor treatment linkage provides a platform to negotiate and develop effective management and research actions across jurisdictional, disciplinary, community and stakeholder boundaries. Keywords: ecological risk assessment, marine ecosystem-based management, risk factor, risk treatment, small scale. Introduction One of the great challenges in implementing marine ecosystembased management (MEBM) is determining what management and research actions will be effective in addressing specific issues at regional and small spatial scales (Cook et al., 2013). Ecological risk assessments (ERAs) for marine biodiversity are often used to prioritize issues but only give broad guidance of how issues might be addressed in the form of strategies (e.g. Hobday et al., 2011; Williams et al., 2011; Samhorni and Levin, 2012). However, at small and regional spatial scales marine natural resource managers still have to make decisions within these strategies about how to manage specific interactions between human uses and ecological components, such as whether to allow foreshore constructions (e.g. marinas) that can potentially have direct and indirect effects on the sustainability of marine biodiversity (Clynick, 2008; Di Franco et al., 2011). In essence, they need to know what to manage, why and how to manage it (Wilson et al., 2007; Astles, 2008; Game et al., 2013). Similarly, scientists need to decide which research questions are the most important to answer to provide specific support to marine natural resource managers to develop effective management actions (McNie, 2007). Two other factors add to the difficulty of marine natural resource management (MNRM) at small and regional spatial scales. First, there are multiple human uses interacting within the same space and time. Each use has multiple stressors that potentially interact, # International Council for the Exploration of the Sea 2014. All rights reserved. For Permissions, please email: K. L. Astles* Linking risk factors to risk treatment in ERA Risk factors and risk treatment The World Health Organisation defines a risk factor as any attribute, characteristic, or exposure of an individual that increases the likelihood of developing a disease or injury (www.who.int/topics/ risk_factors) and are differentiated into types based on their strength of correlation to an outcome and their response to manipulation (e.g. Kraemer et al, 1997, 2001). These factors are used to develop treatments for the management of diseases and injuries (e.g. Kazdin, 2007). The linkage between risk factors and treatments gives clinicians leverage in addressing issues efficaciously. An analogous process in MEBM is the manager making decisions about how to mitigate (i.e. treat) human impacts on marine ecological components. If it is known what is contributing to these impacts, management actions can be developed and implemented that targets these issues to reduce or modify the impacts (e.g. bycatch reduction devices to reduce the catch of non-target species in trawl fisheries; Dayton et al., 1995; Broadhurst et al., 1997). Such points of leverage underpin the effectiveness of management and research for single sector human activities. A risk factor in marine ERA is any attribute or characteristic of an ecological component or exposure of a human activity stressor that increases the likelihood of an impact occurring (adapting the WHO definition). I surveyed ERA papers in the fields of marine ecology and ecotoxicology from 1980 to 2013 to determine the extent to which this term or similar has been used. I found 27% used terms that fit this basic definition Of these papers, 58.3% of ERA studies on marine non-native invasive species and 50% of ERA studies on marine ecosystems and biodiversity used concepts equivalent to risk factor (e.g. Hayes and Landis (2004) used “risk predictors” and “contributors to risk”). However, few of the papers reviewed directly linked these contributors to the treatment of risk, that is, specific management and research actions that could reduce, mitigate, or modify the risk to a marine ecosystem or ecological component. Rather, links were made to potential generalized management strategies, such as spatial management (e.g. Halpern et al., 2007, 2009). Specific management actions in response to factors contributing to risk levels, that is, risk treatments, were mainly identified with respect to a single type of (...truncated)