%0 Journal Article
%T Restoration and enhancement of Atlantic salmon populations: what we have learned from North Iberian rivers
%A Horreo J.L.
%A De La Hoz J.
%A Machado-Schiaffino G.
%A Pola I.G.
%J Knowledge and Management of Aquatic Ecosystems
%D 2012
%I EDP Sciences
%R 10.1051/kmae/2011079
%X Found on the southernmost edge of the species¡¯ natural distribution, North Iberian Atlantic salmon populations are extremely vulnerable to environmental change. In the last few decades, associated with global indicators of climate change, these populations have been experiencing a sharp decline. Efforts have been made to address their decline, principally through stocking, supportive breeding and habitat restoration (enabling accessibility to upstream spawning sites). The efficiency of each of these measures has been different. In this study, focused on the river Sella containing one of the largest Spanish populations as a case study, we demonstrate that accessibility and habitat improvement have been the most efficient measures for increasing population size. Supportive breeding accounts for some level of population increase, but generally lower than 10%. Finally, our review suggests that stocking should be discarded as a restoration method because it encompasses threats to natural variation of Atlantic salmon and also the sympatric brown trout. Situ¨¦es en bordure m¨¦ridionale de la distribution naturelle de l'esp¨¨ce, les populations nord-ib¨¦riques de saumon Atlantique sont extr¨ºmement vuln¨¦rables aux changements environnementaux. Dans les derni¨¨res d¨¦cennies, en relation avec les indicateurs globaux du changement climatique, ces populations ont connu une forte baisse. Des efforts ont ¨¦t¨¦ faits pour enrayer le d¨¦clin, principalement ¨¤ travers l¡¯alevinage, l¡¯¨¦levage de g¨¦niteurs et la restauration de l'habitat (permettant l'accessibilit¨¦ aux fray¨¨res en amont). L'efficacit¨¦ de chacune de ces mesures a ¨¦t¨¦ diff¨¦rente. Dans cette ¨¦tude, ax¨¦e sur la rivi¨¨re Sella contenant l'une des plus grandes populations espagnoles comme ¨¦tude de cas, nous d¨¦montrons que l'accessibilit¨¦ et l'am¨¦lioration de l'habitat ont ¨¦t¨¦ les mesures les plus efficaces pour augmenter la taille de la population. L¡¯¨¦levage de soutien de g¨¦niteurs repr¨¦sente un certain niveau d'augmentation de la population, mais g¨¦n¨¦ralement inf¨¦rieur ¨¤ 10 %. Enfin, notre ¨¦tude sugg¨¨re que l¡¯alevinage doit ¨ºtre abandonn¨¦ comme m¨¦thode de restauration, car elle comporte des menaces ¨¤ la variabilit¨¦ naturelle du saumon Atlantique et aussi de la truite fario sympatrique.
%K stocking
%K restoration
%K connectivity
%K re-colonization
%K Salmo salar
%K alevinage
%K restauration
%K connectivit¨¦
%K recolonisation
%K Salmo salar
%U dx.doi.org/10.1051/kmae/2011079