Utvärdering av målen för programmet krafttag ål

In this report, the 2011-2013 program ’KrafttagÅl’ is post-evaluated, which was jointly operated by the Swedish Agency for Marine and Water Management and a number of hydropower electricity companies, aiming at protection of the eel in Swedish inland waters. Results indicate that the run of silver eels from inland waters will be increased by the agreed amount, even though most of these eels will be produced nearly fifteen years from now. The agreed level of immediate protection has not been and cannot be achieved by means of the measures taken. Recommendations are given for better embedding of this program in the national and international eel protection policies, and for the development of an adequate monitoring for future post-evaluation. The European eel stock is in a decadal decline, all over its distribution. In 2007, EU decided on a stock protection and recovery plan, Regulation (EG) nr 1100/2007. The objective is to protect 40% of the silver eel, escaping to the sea towards its spawning places in the Sargasso Sea, on the other side of the Atlantic Ocean. The Swedish Eel Management Plan includes four different actions: restrictions on the fishery, reduction of hydropower related mortality, restocking, and intensified control. In spring 2010, the former Fiskeriverket signed a memorandum of understanding with the six larger electricity companies, to reduce the hydropower impact to max 60% (i.e. 40% survival) on a voluntary basis. To this end, one could apply: installation of bypasses at hydropower stations; free spilling of water during the migration season; Trap&Transport along power stations; or compensatory restocking; (the first two options have actually not been applied within the current program). In 2011, a joint program “KrafttagÅl” was started, and this report now provides an evaluation of that program. The two objectives for this program were: first, ‘to half the current average hydropower mortality for silver eel in the rivers where signatories own the hydropower’; and secondly, ‘by 2013, the measures taken should correspond to an increase of 100 thousand silver eels escaping freely towards the sea’. To assess the impact of the hydropower and to evaluate protective measures, the abundance of eel upstream of the power station must be quantified, and the relative mortality when passing a station. In the absence of a dedicated monitoring effort for this program, we reconstruct the stock abundance using historical information on the number of elvers recruiting/released into our waters, the catch registered by fishers and on Elvers 1.335 million Growth Survival … 15 year … Adult, silver eel – 211 ton Downstream migration – 181 ton Natural recruitment 0.117 million Restocking 1.218 million Cormorants and seals Fishery – 30 ton Hydropower – 133 ton Elver transport 0.117 million Silver eel T&T - 14 ton +14 ton =62 ton Silver eel run – 48 ton indices of hydropower related mortality estimated for a number of stations. Because of the high age of adult eels (5-30 years or more, mean 15), this requires the availability of long data series. More importantly, actions taken around the year 2000 determine today’s results, and today’s actions will only have full effect by 2030. Objective 1 (mortality) focuses on immediate effects, while objective 2 (increased silver eel run) considers the long-term effects of today’s actions. For the 6 rivers prioritised in this program (Rivers Dalälven, Nyköpingsån, Motala ström, Mörrumsån, Lagan and Göta älv), the total production of silver eel in 2013 is estimated at almost 200ton, 90% of which is derived from restocking (done shortly before 2000). In 2013, the fishery took 30ton, hydropower killed 133ton and 48tons escaped – Trap&Transport added 14tons and by 2030, compensatory restocking will produce an additional 63ton on the West Coast. Due to the long time span between recruitment and escapement, and the imprecisely known survival over these 15 years, these figures are not very accurate. To verify and improve these results, it is recommended to develop a dedicated monitoring program, quantifying stock abundance, survival and impacts. Comparing the aims to the achievements, current results indicate that objective 1 (to half current mortality) has not been achieved, while over the coming twenty years, the 2013 management measures will just achieve objective 2 (an increase of the silver eel run with 100 thousand eels≈ 86tonnes). Increasing the Trap&Transport program can improve survival immediately, but involving even the whole fishery in that will not achieve objective 1 completely. Objective 1 corresponds to the 40% target of the Eel Regulation, but a higher survival will be required to achieve a recovery in the long run. The Swedish Eel Management Plan has set a higher ambition (80-90% survival), and international scientific advice has actually indicated to reduce all mortality to the absolute minimum. Different targets, diverse ambition levels, varying levels of achievement – we recommend to update and revise the objectives. In 2013, 90% of the eel production was derived from restocking, done around the year 2000 with the objective to support the fishery. Nowadays, restocking is more focused on recovery of the stock, mostly in free-flowing rivers on the West Coast, though the prime location – Lake Vänern - actually has 3 power stations downstream. Due to the shift in restocking locations (predominantly from Lake Mälaren, no hydropower downstream, but eastward opening – towards Lake Vänern, three stations downstream, westward opening), the overall hydropower-mortality is actually increasing. The objectives to support/maintain the fishery, to restore the stock and to reduce hydropower mortality are intricately interwoven. Without restocking, there would hardly be an eel stock left in inland waters; without the fishery, there would be little opportunity for Trap&Transport. We recommend to evaluate and discuss the restocking programs and their spatial distribution with all responsible agencies, in order to synchronise objectives and actions.