Kolarctic ENPI CBC – Kolarctic salmon project (KO197) - Report VI Previous spawned salmon having origin from more than 80 stocks improves the catches and widens diversity of the Atlantic salmon life history in Kolarctic salmon project area with reference to the reconditioning of kelts in the River Tana in Norway/Finland Eero Niemelä1, Juha-Pekka Vähä2, Vidar Wennevik3, Esa Hassinen1, Jorma Kuusela1, Jari Haantie1, Pauli Aro1, Satu Metsola1 and Tiia Kalske4 (ed.) 1Finnish Game and Fisheries Research Institute (FGFRI), Teno River Research Station Utsjoki, Finland 2University of Turku (UTU), Finland 3Institute of Marine Research (IMR), Tromsø, Norway 4Office of the County Governor of Finnmark (FMFI), Vadsø, Norway The County Governor of Finnmark, Department of Environmental Affairs Report 3 – 2014 The REPORTs from the Office of the Finnmark County Governor, Department of Environmental Affairs presents results from different works under the governance of the mentioned department. The main aim is to document and to disseminate information on important environmental issues to a broader audience. We highlight that all authors/ contributors in this report are themselves responsible for their own conclusions and evaluations. ISSN 0800-2118 Report no. 3-2014 is mainly published on the internet www.fmfi.no and www.fylkesmannen.no/kolarcticsalmon. Hard copies are produced after request. Printing/ layout: Fylkesmannen i Finnmark For more information concerning this publication contact: Fylkesmannen i Finnmark Miljøvernavdelinga Statens hus 9815 VADSØ [email protected] Cover page photos: Photo on the left - The biggest female previous spawned salmon known (photo: Erik Andreassen) Photo on the right - Previous spawner (photo: Eero Niemelä) Photo 3. Kelt - Audun Rikardsen All other photos Eero Niemelä All figures on by FGFRI – Finnish Game and Fisheries Research Institute This report has been produced with the assistance of the European Union, but the contents can in no way be taken to reflect the views of the European Union. NINA Institute arranged the special permission from Norwegian Directorate of Nature Management for fishing outside the ordinary season. 2 Contents Abstract ....................................................................................................................................................... 4 Main results ................................................................................................................................................. 5 1. Introduction ......................................................................................................................................... 8 2. Material and methods .........................................................................................................................10 3. Results......................................................................................................................................................16 3.1 Wide life history of previous spawners in the salmon catches at sea .................................................16 3.2 Migratory period of previous spawners in the whole Kolarctic salmon project area ...........................18 3.3 Differences in the timing of migrations between the counties and between three areas in Finnmark 22 3.4 Sex distribution and development in maturity along the fishing season .............................................29 3.5 Large variation in length and weight distributions in previous spawning salmon ...............................35 3.5 Stock specific mean lengths and weights of previous spawning salmon .............................................41 3.6 Abundance of previous spawners in the official salmon catches in Kolarctic salmon project area ......52 3.7 Estimated numbers of previous spawners originating from seven Regional Group (RG) areas and places where they have been caught in northern Norway during the official fishing season ....................54 3.8 Life history of previous spawners (alternate and consecutive spawners), their origin from Regional Group areas and distribution in the catches in Northern Norway between May and September in Kolarctic salmon research fishery ............................................................................................................56 3.9 Numbers of stocks in previous spawner and kelt salmon catches along the summer from May to September in Kolarctic salmon research fishery ......................................................................................61 3.10 Weekly numbers and proportions of known origin previous spawners (kelts excluded) in Kolarctic project area in research fishery ...............................................................................................................66 3.11 Catches of previous spawners are overlapping with catches of kelts in the Kolarctic salmon research fishery.....................................................................................................................................................68 3.12 Spatial and temporal distribution of known origin kelts and previous spawners in Kolarctic salmon project area in research fishery ...............................................................................................................70 3.13 Reconditioning from kelt to mature repeat spawner; example from the river Tana. ........................86 Acknowledgements ....................................................................................................................................89 References ..................................................................................................................................................90 3 Abstract In the Kolarctic salmon project (KO197) detailed information was collected from the salmon catches including the biology of salmon in the large coastal area in Northern Norway between the counties Nordland and Finnmark in the years 2011 and 2012. In addition there was salmon scale material from the research fishery in Finnmark County in the years 2008 and 2009. Salmon catches included sea-ages of wild 1SW (1SW, one sea-winter), 2SW, 3SW and 4SW and a large variety of sea-age groups of previous spawners and kelts. Salmon can survive the post-spawning period as a post spawner by staying in the river or by migrating straight after the spawning time into the sea. From smaller rivers, without places like deep pools or small lakes, post spawners must migrate to the sea soon after the spawning. This downward migration soon after the spawning usually occurs between October-December. Perhaps in most of the rivers, especially in large rivers with suitable overwintering habitats like in the rivers Neidenelva, Tanaelva, Lakselva (Porsanger), Altaelva and in the Russian large rivers like Kola, Tuloma, Ponoi, Umba, Petchora salmon is migrating as post spawner into the sea after staying 9-12 months in rivers or even two winters like in the river Petchora. These post spawners are called kelts. After kelts have arrived into the sea they start the reconditioning for the next spawning. It has been unknown where kelts are migrating from the rivers in Kolarctic salmon project area after their arrival into the sea but some satellite tagging results indicate that their migration routes goes straight northwards from Finnmark. After surviving the reconditioning period of one, two or even three years they migrate towards their rivers of origin. Some, but very few salmon are reconditioning in a short period during the summer when they left the river as kelt and then ascending into their river of origin. Previous spawning salmon can have two distinct groups; reconditioning takes place in short time like in some months followed the spawning in previous autumn and that group of salmon is called consecutive spawners. Post-spawners that need one or more years to recondition for the following spawning are called alternate spawners. 4 Main results Previous spawners occurred in the salmon catches presenting reconditioned fish from all the first time spawners of 1-4SW salmon. In Kolarctic salmon research fishery reconditioned fish of 17 different sea-age groups of salmon were caught. The most common previous spawner salmon sea-age groups were those fish which are alternate spawners (1S1+, 2S1+, 3S1+). These salmon were on their way to spawn for the second time in their life after one full reconditioning year at sea after they have had their first spawning in the ages of 1SW, 2SW or 3SW. In the salmon material those fish with the ages of 1S+, 2S+ and 3S+ fishes represented kelts out of which some salmon could ascend into the rivers for repeated spawning as consecutive spawners after very short reconditioning period at sea. These kelts were caught all over the fjord and coastal areas. Material collected only from Finnmark County at sea in 2008, 2009, 2011 and 2012 indicated that the most important sea-age groups within previous spawners and kelts were 1S1+ (47%), 2S1+ (15%), 1S+ (13%), 2S+ (10%), 3S1 (8%), 3S+ (3%) and in addition 4S+ and 4S1+ represented both with less than 1%. Other sea age groups formed 4%. In the catches of male salmon, previous spawners made high proportion in the length group between 80-95 cm fish. Within the largest male salmon previous spawners made 25-35%. The largest female salmon were all previous spawners. Previous spawners are contributing the largest females into the catches so that more than 75% from fish with the length between 110 and 120 cm were previous