{"id":22697,"date":"2026-04-20T08:41:24","date_gmt":"2026-04-20T06:41:24","guid":{"rendered":"https:\/\/asleman.org\/?post_type=60_secondes&#038;p=22697"},"modified":"2026-04-20T08:41:24","modified_gmt":"2026-04-20T06:41:24","slug":"n121-vairon-petit-poisson-mais-grand-bioindicateur","status":"publish","type":"60_secondes","link":"https:\/\/asleman.org\/en\/60_secondes\/n121-vairon-petit-poisson-mais-grand-bioindicateur\/","title":{"rendered":"No. 121: Gudgeon, a small fish but a great bioindicator"},"content":{"rendered":"<p>Le <a href=\"chatgpt:\/\/generic-entity?number=0\">Vairon<\/a>, a small carp between 5 and 10 centimetres, has been voted Fish of the Year 2026 by the <a href=\"chatgpt:\/\/generic-entity?number=1\">Swiss Fishing Federation<\/a>. Immediately recognisable by its slender body with silvery reflections, the male transforms during the breeding season: blood-red belly and lips, emerald-green flanks and small white tubercles on its head.<\/p>\n<p>The dace primarily lives in tributaries and coastal areas with moderate currents, where it seeks clear, fresh, well-oxygenated waters and gravelly bottoms, essential for reproduction. As a gregarious species, it moves in compact shoals that disorient predators. When an individual is injured, its skin releases an alarm substance that warns its fellows.<\/p>\n<p>Recent genetic research reveals that at least four distinct species coexist in Switzerland: the Italian riffle minnow (<em>Phoxinus lumaireul<\/em>), the Mediterranean minnow (<em>Phoxinus septimaniae<\/em>), the Danube minnow (<em>Phoxinus csikii<\/em>and a recently identified lake minnow in the pre-alpine great lakes<em>Phoxinus<\/em> sp. nov.). The species long considered indigenous, <em>Common minnow<\/em>, would not be present in Switzerland. This diversity profoundly alters the understanding of their distribution and vulnerability.<\/p>\n<p>A fundamental link in the food chain, the minnow is a sensitive species and an excellent bioindicator of habitat quality. Obstacles to migration, silting of riverbeds, disappearance of shallow areas, lack of natural structures, chronic pollution from pesticides and micropollutants, excess nutrients and climate warming are weakening its populations.<\/p>\n<p>Once visible near the shores of Lake Geneva, the minnow was not recorded in the last major study of fish populations in 2014. During this study, not a single individual was caught, despite 890 fishing attempts. Last observed in 2003, its absence since then raises a major question: how many species disappear without being noticed? Let's protect the quality of habitats and waters to preserve species diversity.<\/p>\n<p>\ud83d\udcf7 Photo: Jonas Steiner, \u00abFish of the Year\u00bb campaign\u00bb<\/p>\n<p>Source <a href=\"https:\/\/sfv-fsp.ch\/fr\/projets\/poisson-de-lannee\/vairon-2026\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">Swiss Fishing Federation<\/a> and <a href=\"https:\/\/museeduleman.ch\/poisson-de-l-annee-2026\/\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">Lake Geneva Museum<\/a><\/p>\n<p>&nbsp;<\/p>","protected":false},"featured_media":22700,"template":"","mots-cles":[489,387,487,488],"class_list":["post-22697","60_secondes","type-60_secondes","status-publish","has-post-thumbnail","hentry","mots-cles-biodiversite","mots-cles-leman","mots-cles-poisson","mots-cles-vairon"],"acf":[],"ase":null,"_links":{"self":[{"href":"https:\/\/asleman.org\/en\/wp-json\/wp\/v2\/60_secondes\/22697","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/asleman.org\/en\/wp-json\/wp\/v2\/60_secondes"}],"about":[{"href":"https:\/\/asleman.org\/en\/wp-json\/wp\/v2\/types\/60_secondes"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/asleman.org\/en\/wp-json\/wp\/v2\/media\/22700"}],"wp:attachment":[{"href":"https:\/\/asleman.org\/en\/wp-json\/wp\/v2\/media?parent=22697"}],"wp:term":[{"taxonomy":"mots-cles","embeddable":true,"href":"https:\/\/asleman.org\/en\/wp-json\/wp\/v2\/mots-cles?post=22697"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}