{"id":62941,"date":"2026-07-19T23:01:00","date_gmt":"2026-07-19T23:01:00","guid":{"rendered":"https:\/\/www.newscientist.com\/article\/2580119-auto-draft\/"},"modified":"2026-07-19T23:01:00","modified_gmt":"2026-07-19T23:01:00","slug":"hunter-gatherers-introduced-fish-to-a-mountain-lake-7000-years-ago","status":"publish","type":"post","link":"https:\/\/hoo.central12.com\/fugic\/2026\/07\/19\/hunter-gatherers-introduced-fish-to-a-mountain-lake-7000-years-ago\/","title":{"rendered":"Hunter-gatherers introduced fish to a mountain lake 7000 years ago"},"content":{"rendered":"\n\n\n<figure class=\"wp-block-image size-full\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1350\" height=\"901\" src=\"https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg\" alt=\"\" class=\"wp-image-2580121\" srcset=\"https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg 1350w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=150,100 150w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=300,200 300w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=768,513 768w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=600,400 600w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=400,267 400w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=900,600 900w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=1200,800 1200w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=196,131 196w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=301,201 301w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=415,277 415w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=602,402 602w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=830,554 830w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=105,70 105w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2026\/07\/SEI_305290666.jpg?resize=210,140 210w\" sizes=\"(max-width: 1350px) 100vw, 1350px\"><figcaption class=\"wp-element-caption\"><div class=\"wp-image__caption--icon\"><svg width=\"15\" height=\"15\" viewbox=\"0 0 15 15\"><use href=\"https:\/\/www.newscientist.com\/wp-content\/themes\/newscientist\/images\/icon-circle-chevron.svg#icon-circle-chevron\"><\/use><\/svg><\/div><div class=\"wp-image__caption--text\">The exposed bed of Lake Tesse in Norway, where archaeologists found ancient fish traps<\/div><div class=\"wp-image__caption--credit\">Magne Samdal, Museum of Cultural History, University of Oslo<\/div><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Hunter-gatherers transported brown trout into the mountains of Norway at least 7000 years ago so they could be harvested during summer foraging trips into the highlands.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That is the only possible explanation for how fish could have populated isolated mountain lakes that had been covered by a kilometres-thick ice sheet for tens of thousands of years, says <a href=\"https:\/\/www.khm.uio.no\/english\/about\/organisation\/archaeology-department\/staff\/axelm\/\">Axel Mj\u00e6rum<\/a> at the University of Oslo, Norway.<\/p>\n\n\n\n\t<div class=\"read-more__standard wp-block-newscientist-read-more\">\n\t\t<a class=\"read-more__standard--wrapper no-animation\" href=\"https:\/\/www.newscientist.com\/article\/2502872-ancient-dna-may-rewrite-the-story-of-icelands-earliest-settlers\/\">\n\t\t\t<strong>Read more<\/strong>\n\t\t\t<p>Ancient DNA may rewrite the story of Iceland\u2019s earliest settlers<\/p>\n\t\t<\/a>\n\t<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cThis is the oldest documented example of human-mediated translocation of fish in the world,\u201d says Mj\u00e6rum.<\/p>\n<div class=\"advert-wrapper advert__mid-article\">\n\t<div class=\"advert\">\n\t\t<div class=\"advert__inner\">\n\t\t\t\t\t\t\t<p class=\"advert__copy\">\n\t\t\t\t\tAdvertisement\t\t\t\t<\/p>\n\t\t\t\t\t\t<div class=\"advert__slot\" id=\"mid-article-slot\">\n\t\t\t\t<script>\n\t\t\t\t\tif( window?.adverts?.addToArray ) {\n\t\t\t\t\t\twindow.adverts.addToArray( {\n\t\t\t\t\t\t\t\"pos\": \"mid-article-slot\"\n\t\t\t\t\t\t} );\n\t\t\t\t\t}\n\t\t\t\t<\/script>\n\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n<\/div>\n\n\n\n\n<p class=\"wp-block-paragraph\">Until around 8400 years ago, Lake Tesse, at an elevation of around 850 metres, was covered by the Fennoscandian ice sheet, leaving an ecological blank canvas once it retreated.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Yet before it was transformed for hydropower storage in the 1940s, Lake Tesse was regarded as one of the richest brown trout waterways in Norway, yielding 9 tonnes of the fish annually.<\/p>\n\n\n\n<div class=\"wp-block-newscientist-newsletter-promotion\">\n\t<div class=\"newsletter-promotion__content\">\n\t\t<p class=\"newsletter-promotion__tagline\">Subscriber-only newsletter<\/p>\n\t\t<h4 class=\"newsletter-promotion__title\">\n\t\t\tSign up to Our Human Story\t\t<\/h4>\n\t\t<p class=\"newsletter-promotion__excerpt\">\n\t\t\t\t\t<\/p>\n\t\t<div class=\"newsletter-promotion__actions\">\n\t\t\t<a class=\"button button--secondary button--has-icon\" href=\"https:\/\/www.newscientist.com\/sign-up\/our-human-story\/\">\n\t\t\t\t<span>Sign up to newsletter<\/span>\n\t\t\t\t<svg width=\"18\" height=\"18\" viewbox=\"0 0 24 24\" style=\"--fill-color: #000\">\n\t\t\t\t\t<use href=\"https:\/\/www.newscientist.com\/wp-content\/themes\/newscientist\/images\/icon-arrow-right.svg#icon-arrow-right\"><\/use>\n\t\t\t\t<\/svg>\n\t\t\t<\/a>\n\t\t<\/div>\n\t<\/div>\n\t<div class=\"newsletter-promotion__background\">\n\t\t<span class=\"newsletter-promotion__gradient\"><\/span>\n\t\t<div class=\"newsletter-promotion__image__wrapper\">\n\t\t\t<div class=\"image__wrapper\">\n\t\t\t\t<img decoding=\"async\" width=\"600\" height=\"450\" src=\"https:\/\/www.newscientist.com\/wp-content\/uploads\/2025\/06\/16102056\/our_human_story_2025_ed_newsletter_landingtiles_2400px2.jpg?w=600&amp;h=450&amp;crop=1\" class=\"attachment-4x3-sm size-4x3-sm wp-post-image\" alt=\"\" sizes=\"(min-width: 432px) 412px, (min-width: 300px) 373px, 100vw\" srcset=\"https:\/\/www.newscientist.com\/wp-content\/uploads\/2025\/06\/16102056\/our_human_story_2025_ed_newsletter_landingtiles_2400px2.jpg?resize=300,225 300w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2025\/06\/16102056\/our_human_story_2025_ed_newsletter_landingtiles_2400px2.jpg?resize=400,300 400w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2025\/06\/16102056\/our_human_story_2025_ed_newsletter_landingtiles_2400px2.jpg?resize=600,450 600w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2025\/06\/16102056\/our_human_story_2025_ed_newsletter_landingtiles_2400px2.jpg?resize=800,600 800w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2025\/06\/16102056\/our_human_story_2025_ed_newsletter_landingtiles_2400px2.jpg?resize=1024,768 1024w, https:\/\/www.newscientist.com\/wp-content\/uploads\/2025\/06\/16102056\/our_human_story_2025_ed_newsletter_landingtiles_2400px2.jpg?resize=1920,1440 1920w\">\t\t\t<\/div>\n\t\t<\/div>\n\t<\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">While it has long been suspected that humans had a hand in establishing the brown trout population in Lake Tesse, we had no idea how long ago this happened.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Alternative ideas have included transportation by birds or natural migration of fish and eggs upstream. But most Norwegian mountain lakes, including Lake Tesse, only had brown trout, and geographical features such as large waterfalls make natural dispersal upstream impossible.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Mj\u00e6rum and his colleagues studied the partially buried remains of elaborate fish traps, discovered in 2022 when the lake level was lowered.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Radiocarbon dating showed that the oldest trap dated from around 4950 BC. By correlating the recovered wood with the pine tree ring chronology available for the central Scandinavian mountains, the team was also able to precisely date some of the younger posts.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">One was felled between spring 2669 BC and winter 2669-2668 BC, and another 12 years later during the winter of 2657-2656 BC, demonstrating that the traps must have been maintained to keep them in good working order.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cTherefore, it is possible that this form of trap fishing was ongoing in Tesse during much of the period between 5000 and 2650 BC,\u201d says Mj\u00e6rum.<\/p>\n\n\n\n\t<div class=\"read-more__standard wp-block-newscientist-read-more\">\n\t\t<a class=\"read-more__standard--wrapper no-animation\" href=\"https:\/\/www.newscientist.com\/article\/2515260-the-surprising-origins-of-britains-bronze-age-immigrants-revealed\/\">\n\t\t\t<strong>Read more<\/strong>\n\t\t\t<p>The surprising origins of Britain\u2019s Bronze Age immigrants revealed<\/p>\n\t\t<\/a>\n\t<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">The transport of fish into the lakes is an early example of people managing the environment to provide food, centuries before the advent of farming in Scandinavia. There is evidence that fish farming began even earlier in other parts of the world, <a href=\"https:\/\/whc.unesco.org\/en\/list\/1577\/\">including channels and traps for catching eels built in Australia 8600 years ago.<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">How people transported the fish is unknown, but they may have used waterskins. People probably stayed in the mountains for part of the summer season, hunting reindeer and fishing, but spent the winters in the valleys or along the coast where the climate was milder, says Mj\u00e6rum.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cA good and predictable food supply also made longer stays possible, not only for hunters aiming for big game, but for whole family groups,\u201d he says.<\/p>\n\n\n<div class=\"journal-reference__wrapper wp-block-newscientist-read-more\">\n\t<strong>Journal reference:<\/strong>\n\t<p>\n\t\t<em>Antiquity<\/em>\n\t\t<a class=\"journal-reference__link no-animation\" href=\"https:\/\/doi.org\/10.15184\/aqy.2026.10392\">\n\t\t\tDOI: 10.15184\/aqy.2026.10392\t\t<\/a>\n\t<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Many centuries before the advent of agriculture in Norway, ancient people transported fish into mountain lakes to create a source of food, then built wooden traps to catch them<\/p>\n","protected":false},"author":890,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[940,3449],"tags":[],"class_list":["post-62941","post","type-post","status-publish","format-standard","hentry","category-archaeology","category-humans"],"_links":{"self":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/62941"}],"collection":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/users\/890"}],"replies":[{"embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/comments?post=62941"}],"version-history":[{"count":3,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/62941\/revisions"}],"predecessor-version":[{"id":62977,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/posts\/62941\/revisions\/62977"}],"wp:attachment":[{"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/media?parent=62941"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/categories?post=62941"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hoo.central12.com\/fugic\/wp-json\/wp\/v2\/tags?post=62941"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}