{"id":294172,"date":"2026-02-20T22:46:13","date_gmt":"2026-02-20T22:46:13","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/294172\/"},"modified":"2026-02-20T22:46:13","modified_gmt":"2026-02-20T22:46:13","slug":"it-spans-2-7km-borders-two-countries-and-can-be-seen-from-space-and-is-home-to-one-of-the-most-daring-animals-on-earth","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/294172\/","title":{"rendered":"It spans 2.7km, borders two countries and can be seen from space \u2013 and is home to one of the most daring animals on Earth"},"content":{"rendered":"

When it comes to nest building, few animals on the planet are quite as bold as the great dusky swift.<\/p>\n

Found across Brazil, in northeastern Argentina and eastern Paraguay, these large, grey-brown swifts roost around waterfalls, often choosing nest spots directly beside and even behind the gushing torrents.<\/p>\n

A waterfall may seem like a treacherous place to lay eggs<\/a>, but the steep walls combined with the tumbling water offer good protection against both climbing and flying predators.<\/p>\n

Once a suitable site has been chosen, these daring birds build a disc-shaped nest using moss, pebbles and mud, typically laying just one egg within it.<\/p>\n

One of the most famous places to see great dusky swifts is Iguazu Falls on the border of Brazil and Argentina. Standing around 80 metres tall, spanning 2.7 kilometres (1.7 miles) and made up of hundreds of cascades, this is the largest waterfall system in the world. <\/p>\n

Iguazu Falls is so big it can be seen from space \u2013 images of the cascades<\/a> have been captured from the International Space Station<\/a>.<\/p>\n

Hundreds of great dusky swifts fly over the cascading waters of Devil’s Throat, part of the Iguazu Falls waterfall system. Credit: Getty<\/p>\n

Yet despite the impressive size of Iguazu, many swift adults choose the damp cliffs behind the raging falls as a place to rear their young. <\/p>\n

Because of this, fledglings are faced with the formidable challenge of not only taking to the wing off the sheer cliffs, but doing so through a deluge of water.<\/p>\n

Two great dusky swifts fly through the crashing waters of Iguazu Falls to their nests behind. Credit: Getty<\/p>\n

\u201cThe chicks have never seen the world beyond the falling waters,\u201d said\u00a0David Attenborough<\/a>\u00a0of the great dusky swift fledglings in the 2019 BBC documentary,\u00a0Seven Worlds, One Planet<\/a>. \u201cUnless they can find a way through, they will not survive.<\/p>\n

\u201cAmazingly, driven by blind instinct, chicks do manage to power their way through,\u201d adds Attenborough. \u201cThese remarkable birds have colonised a niche in which few can survive.\u201d<\/p>\n

In Pictures: Great dusky swifts at Iguazu Falls
\n\"GreatA great dusky swift returns to its roost behind the falls with nest material. Credit: Getty
\n\"GreatThe great dusky swift is relatively large compared to other swifts, measuring about 18 centimetres in length. Credit: Getty
\n\"GreatA group of swifts clings to a damp cliff face at Iguazu Falls. Credit: Getty
\n\"IguazuIguazu Falls is so large it can be seen from the International Space Station. Credit: Getty
\n\"GreatThe birds have dark grey-brown bodies and pale heads. Credit: Getty
\n\"HundredsA flock of swifts dwarfed by the falls behind. Credit: Getty
\n\"HundredsGreat dusky swifts are insectivores, meaning they feed on insects. Credit: Getty
\n\"GreatA glorious rainbow arches over a small flock of swifts. Credit: Getty
\n\"GreatGreat dusky swifts weigh around 50 to 100\u00a0grams. Credit: Getty
\nAerial footage shows the incredible size of Iguazu Falls. Credit: Getty<\/p>\n

Top image: Iguazu Falls. Credit: Getty<\/p>\n

More amazing wildlife stories from around the world<\/p>\n","protected":false},"excerpt":{"rendered":"When it comes to nest building, few animals on the planet are quite as bold as the great…\n","protected":false},"author":2,"featured_media":294173,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[111,139,69,147,406],"class_list":["post-294172","post","type-post","status-publish","format-standard","has-post-thumbnail","category-wildlife","tag-new-zealand","tag-newzealand","tag-nz","tag-science","tag-wildlife"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/294172","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=294172"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/294172\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/294173"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=294172"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=294172"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=294172"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}