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Presentation on the Principles of Fisheries Management given at the Freshwater Fisheries Forum Steering Group in Perth on 21st June 2006 by Alastair Stephen Simon McKelvey What is Fisheries Management? The basic principle is simple: Provide fish that can be caught by those with a legitimate right to catch them. When considering natural fish stocks this means providing an exploitable excess of fish above the biological limit of the population. If exploitation/mortality exceeds the natural biological limit, the stock of fish will decline and the fishery will become rapidly unsustainable How do you do it ? To effectively produce sustainable levels of catchable fish from a population one needs to fully understand: Species involved - spawning requirements /escapement Size and age structure of the population Factors effecting the population – recruitment, dispersal, mortality, disease, predation etc How the target species interacts with other fish species Other factors the Fishery Manager needs to understand Factors effecting the habitat in which the fish are living: Physical and chemical properties of the water body – still waters and flowing waters Productivity and its measurement Energy flow / food webs – who eats who Fish feeding requirements / limitations Levels of predation and mortality How does the manager make the fishery better ? – Toolbox approach Improve habitat – bank protection, plant/cut down riparian vegetation Improve in-stream structures Maintain acceptable water quality Maintain/improve access for migratory fish Control poaching activities/control predation Reduce exploitation by altering angling/netting pressure Alter recruitment to the population Influence surrounding land management practices Consider stocking Prerequisites for successful Manager Full working knowledge of the following: Freshwater Biology Fishing and sampling methodologies – including all relevant protocols for identifying and quantifying their fishery resources Water quality and its influence Bailiffing and Keepering and the Legal aspects of their operations Fisheries improvement methodologies Fishery Management Planning Fishery Management Plans Need framework to give consistency of plan production. Based on best scientific evidence available. Framework must be flexible enough to cover all species and regions. Formalised thought process that develops management actions from data. Cyclical process which evolves, both driven by research and identifying further research needs. Advantages Encourages a strategic view of management. Prioritises issues and works required. Identifies needs for resources and finance. Gives continuity of management- staff / management changes. Proactive rather than reactive management. More Advantages All stakeholders can see and understand the reasons for management actions and the research and analysis supporting them. Management and research linked in an evolving process. Linkage with wider catchment and basin planning process. Funding opportunities SFCC Fishery Management Plan Framework Introduction Aims and objectives Description Analysis and evaluation Prescriptions Monitoring and review Appendices Description Aims and objectives Monitoring and review analysis prescriptions Aims and objectives Sets out the scope, duration and objectives of the plan.and also how it relates to other plans and as part of the WFD planning process. Should set out aims and objectives for fish species other than trout, salmon and other commercially important species. Description • • • • Description of catchment and catchment use Description of fish stocks by species Description of fisheries Description of habitat: include distribution and suitability of habitat, location of obstructions to migration, location of degraded habitat etc. Analysis and evaluation Assessment of stock and fishery performance. Limiting factors / constraints Opportunities Wide range of analytical tools may be used in stock assessment. Improved tools should be sought and applied as the plan is reviewed and updated. An inventory of gaps in knowledge will also help to guide research programmes both locally and nationally. Prescriptions A detailed list of prescriptions for each subcatchment and species covered by the plan. Works should be prioritised, timetabled and costed. These prescriptions are likely to be in tabular form with column headings; issue, action, costing/timetable, funding/lead agency, priority, notes. This can then form the basis of an annual work programme over the period of the plan. Some prescriptions may be outside present resources available but can be identified to be carried over into next phase of plan. Monitoring and review This ensures that the plan achieves the objectives detailed in the first section and is also sufficiently flexible to adapt to changing circumstances and new data. This is likely to take place annually or at key milestones in the implementation of the plan. Appendices Include the survey data on which the plan is based and relevant documents. May document where this data is stored rather than include in the plan. Plan Structure For a large river system a series of chapters and sub chapters are needed. A regional plan to cover a number of small rivers could use a similar structure. Conon Blackwater Salmon Trout Bran Pike Meig Other Fish sp Orrin Lower Conon River Glascarnoch An example of the application of the SFCC planning process to the River Glascarnoch, a tributary of the Blackwater. Where the aim is to optimise the sustainable production of Atlantic salmon Description SFCC Habitat Survey carried out on Glascarnoch. Divided into 250m lengths, detailed habitat parameters recorded for each length. Data entered into GIS compatible database. Preliminary electro-fishing carried out. 3.3 km of river with a wetted area of 60,975 square metres. Distribution of flow types # # # # # # # # # Glas c a rn oc h. tx t Sm Dp Sp Dg Sg Ru Ri To Lc s lo ch _c on .s hp Ceh 05_ c on. sh p 14 - Crom arty C oas ta l 15 - Rive r A ln es s 16 - Rive r G las s 17 - Rive r Co non # # # # # Distribution of substrate types. # # # # # # # # G la s c arn oc h. tx t Si Sa Gr Pe Co Bo Be Ob Lc s loc h _c on .s hp C eh0 5_c o n.s hp 14 - C ro m ar ty C oa s ta l 15 - R iv e r Aln es s 16 - R iv e r Gl as s 17 - R iv e r C on on # # # # # # River Conon Hydro-electric Scheme Glascarnoch River Analysis-water quality and quantity Electro-fishing found four year classes of brown trout present, indicating that both water quality and quantity were suitable for salmonids. There is no compensation flow agreed for Glascarnoch. The present flow is due to leakage from the dam and surface run off from surrounding land. Analysis-Access The heck at the junction with the Blackwater prevents salmon access to the Glascarnoch river. It was constructed in the 1950s because no compensation flow had been agreed. Analysis-habitat suitability By combining the distribution of flow, substrate types and other habitat parameters an assessment of habitat suitability was made. Of the 60,975 sq m wetted area 39,375 sq m was suitable to support Atlantic salmon # ##### ######## Gla s c arn oc h.tx t # # no ye s Lc s loc h _c on .s hp C eh0 5_c o n.s hp 14 - C ro m ar ty C oa s ta l 15 - R iv e r Aln es s 16 - R iv e r Gl as s 17 - R iv e r C on on Analysis-potential To stock this area 170,000 salmon fry would be required. Taking the known smolt production from the wetted area of the neighbouring River Bran this should produce 2,300 extra smolts a year. This would give almost a 10% increase in estimated production of the Blackwater. Prescription Issue Agency Works Year Cost Access for smolts Hydro Provide downstream access at heck 2 £4000 Access for adults Conon DSFB Not possible – stock with fry of Blackwater origin 1-6 £1500 Water flow Hydro Short term don’t fix 1-6 leak. Long term comp flow £0 £? Monitor Conon DSFB Add to electro1-6 fishing programme £300 Prescription-stocking Conon DSFB began stocking in 2003 with unfed salmon fry. The parents of these fry were caught in the River Blackwater to ensure genetic suitability. Prescription Hydro have provided downstream access for smolts by installing a by-pass culvert at the heck. Monitoring Glascarnoch River electro-fished to SFCC protocol in August 2005. Found good densities comparable with best of Blackwater sites 3.5 salmon fry /m sq 0.69 salmon par / m sq 0.19 trout / m sq Application of Management Plan process This example is from a fishery management project with the aim of sustaining salmon stocks. The same decision making process applies equally well to managing hill loch brown trout and char, protecting lamprey habitat or monitoring the status of eels. In many cases where little information exists, the first phase of a plan will be to set out a programme to collect the data which will be needed for future management decisions.