Report: How did the workshop help EcoFish?

Transcription

1 Report: How did the workshop help EcoFish? The EcoFish Approach to Fisheries Advice Workshop arranged by the project Ecosystem Dynamics and Fish Stocks (EcoFish) May 15 th and 16 th 2006 Villa Skjoldnes, Sundtsveg 57, Nesttun, Bergen The workshop included a broad specter of issues, all related to environmental issues or ecosystem management. Below are a couple of sentences from each presentation focusing only on how to relate the talks to EcoFish. All presentations can be found on the EcoFish website. The atmosphere during the workshop was very positive and the participants contributed actively in the numerous discussions. We observe that there is a lot of enthusiasm about the ecosystem approach and what may be possible to accomplish, but there is also some skepticism. There is still a challenge on the understanding of what the ecosystem approach actually is and what knowledge, science disciplines and form of advice it takes to get there. Part of this confusion is real in the sense that managers have defined it differently in different contexts and places in the world. Still, its interpretation in many cases is still open and the science communities are struggling (and maybe fighting?) with deciding what the ecosystem approach demands from us, the science community. EcoFish is a project where the topics of the ecosystem approach are reduced to ecosystem impacts on the exploited fish stocks. Yet, the workshop demonstrates quite different perspectives on how to approach the issue. We can definitely learn from how managers and scientists have approached the problem elsewhere on the globe. Several pieces of advice from the participants are articulated below. Mike Sinclair presented the steps of making the ESSIM plan operational. This was a topdown process, beginning with the management objectives and ending with indicators and the like. This is the quite different from the Norwegian Barents Sea approach, where the management objectives and the indicators have been handled parallel and separately, causing difficulties in connecting the two. It would be interesting to copy this exercise (which was done by scientists) although the scope was much wider than that of EcoFish. This will be considered later. He also presented three points on research needs for EA: causality (explanatory power), cumulative impacts and prioritization based on ecosystem objectives framework. The first point gives EcoFish an alternative possibility in making tools for the EA: to explain changes in the ecosystem just to satisfy the public. He demonstrated several 1

2 cases from Canada, but we have several interesting cases in our waters too. Would we like to pick some of these? Cisco Werner gave a very relevant talk. EcoFish should consider his help/advice on finding literature on detecting changes in the ecosystem, how to integrate models the way PICES carried out the sensitivity analysis (presented at ukens orientering) and other uncertainty perspectives. Svein Sundby highlighted the importance of understanding the processes behind correlations. Can we develop further the work on advection? In the Barents Sea? He presented a list of temperature dependent processes. How can we use this list in EcoFish? Richard Nash presented a broad specter of indicators where there seems to be causal links between indicator and issue. It is not yet decided which of these, or others, we will work with in EcoFish. When we do, we need to take into consideration why the issues (indicators) are interesting or important in an ecosystem approach. Webjørn Melle Plankton can be important when finding explanations on changes in the ecosystem. This is the ecosystem approach not on an annual basis, but more ad hoc: can knowledge on plankton explain this particular change in the ecosystem? Plankton concentrations can help growth predictions in fish stocks on a more annual basis, particularly in a precautionary context. Frode Vikebø presented a talk on drift and settlement patterns of NEA cod larvae. Should EcoFish contribute in testing his ideas? Christian Jørgensen presented work on skipped spawning that we might consider a way of implementing in a harvest control rule or change the existing concept of spawning stock biomass. What has been done to implement such factors? Maybe we could make a system of which factors are most important for evaluating the production potential of a stock? Sigurd Tjelmeland gave a presentation related to fish stock assessment. He divided the problem of the ecosystem approach into estimation, short term predictions and harvest control rules (based on long term simulation). He argued that the main environmental contribution to assessments is natural mortality (stock interactions), relative stock sizes and ecosystem based improvement of survey indices, to short term: growth, temperature, natural mortality (because an objective is to manage fish stocks in relation to other fish stocks (and birds and mammals)) and uncertainties associated with environmental forces and to harvest control rules: ecosystem effects on recruitment (like temperature, larval drift and predation). He also pointed to the importance of acceptance among stakeholders and the high expectations to the scientists and what if we cannot deliver? 2

3 Howard Browman presented a range of literature that is very relevant for EcoFish (see presentation). The defining of marine protected areas (MPAs) is an example where ecologists had assisted with major contributions. He emphasized the extraordinary complexity of food web interactions and asked whether this was possible to model mathematically to answer specific scientific problems or questions of importance to society. An alternative is to make conceptual models. He discussed whether we need ecology to reduce fishing pressure, create MPAs or ecological risk assessment and argued that if we want to move from an a posteriori description to predictions we need knowledge on causality. There are two pathways related to causality: proximate mechanisms and ultimate mechanisms (eco evolutionary). The ecosystem approach needs an inter disciplinary approach rather than multi disciplinary one. Are Dommasnes presented the preparatory work for the White paper on the management plan for the Norwegian part of the Barents Sea: the scientific basis for indicators and Ecological Quality Objectives. The challenge still maintains on how to make the indicators operational. Many of these indicators are not relevant for EcoFish, but EcoFish can make some effort on how to make some of the indicators operational. In addition, this preparatory work has resulted in a total list of time series in the Barents Sea. Einar Svendsen presented his view on what ecosystem based research should focus on and presented several topics on processes where climate is important. Some of them we will work on in EcoFish. Vertical distribution transport/behavior of larvae. Challenge for observation. Sam Subbey and Sondre Aanes presented techniques on handling time series and concerns on the use of time series. These are relevant for EcoFish, both concerning stock assessment and indicators, when considering how the time series and indicators can be used in a management perspective. There seemed to be two opposite parties at the workshop: one opposing to the statistical approach, focusing on the importance of processes and the other focusing on the quality of information. In EcoFish we need both views. Sondre also pointed to the problem of non reported catches. Per Sandberg argued that the ecosystem approach to fisheries still would be about harvest control rules. Essential knowledge is factors affecting growth, structure, processes and species interactions. In EcoFish we need to think on alternative ways to incorporate ecosystem information in harvest control rules. Poul Degnbol stressed that the ecosystem approach is about objectives: the ecosystem influence on fish stocks in stock assessment and the fishing operations impact on the ecosystem, but also about societal values. He differentiated between Ecosystem Based Fisheries Management takes major ecosystem components and services into account, and 3

4 the Ecosystem Approach to Fisheries which also balance diverse societal benefits. The incremental approach to EAF is when considering ecosystem services when deciding Blim, like food availability, predation and biodiversity. Further he claimed that indicators for overall ecosystem health are not useful for decisions, but gives directions for actions. When deciding target values, gear impact and by catch should be considered. He stressed that the solution is not to remove uncertainty but to design management so that it is robust to uncertainty. We should learn by experience from implementation rather than predict, but have long term perspectives. More transparency, more dialogue and performance criteria were called for. By reducing fishing effort, most ecosystem concerns are addressed simultaneously. We have to start with this, and the rest will be fine tuning. General: We need to make an EcoFish definition of indicator. PROGRAM DAY 1 Kjellrun Hiis Hauge Mike Sinclair Cisco Werner Svein Sundby Richard Nash Webjørn Melle Frode Vikebø Christian Jørgensen Sigurd Tjelmeland Howard Browman DAY 2 Are Dommasnes Einar Svendsen and Olav Rune Godø Sam Subbey Sondre Aanes Poul Degnbol Welcome, and an introduction to EcoFish and the workshop What are the expected gains of the ecosystem approach to the fisheries? The Canadian perspective Observational and modeling approaches to detecting change in ecosystems Ecosystem based advice in a climate perspective What can indicators on different ecosystem levels tell us? How do plankton influence fish stock dynamics? How sensitive is drift and settlement patterns of NEA cod larvae to vertical distribution? Individual state and individual variation in fish models What can we take into account in fisheries advice? The ecosystem based approach to fisheries management is missing the ecology Indicators, the challenge of making them operational. Modeling and observing the ecosystem the challenge of integration Time series and fish stock assessment Indicators and uncertainty, the challenge of separating signals from noise The precautionary approach from the perspective of 4

5 Per Sandberg Mike Sinclair ecosystem based management or the other way around Perspectives on the ecosystem approach from a fishery manager Concluding remarks 5