{"id":73600,"date":"2025-01-08T09:21:38","date_gmt":"2025-01-08T16:21:38","guid":{"rendered":"https:\/\/in.nau.edu\/news\/?p=73600"},"modified":"2025-01-09T10:44:27","modified_gmt":"2025-01-09T17:44:27","slug":"harrison-extinction-research","status":"publish","type":"post","link":"https:\/\/in.nau.edu\/news\/harrison-extinction-research\/","title":{"rendered":"One-quarter of freshwater animals at risk of extinction, new research shows"},"content":{"rendered":"

A global study published today in Nature<\/a> found that one in every four freshwater animal species is at risk of extinction. It\u2019s the largest study of its kind to look at freshwater species like fishes, dragonflies, crabs and shrimps throughout the world.<\/span>\u00a0<\/span><\/p>\n

The study, led by the International Union for Conservation of Nature and co-authored by international experts throughout the world, including Northern Arizona University conservation biologist <\/span>Ian Harrison<\/span><\/b>, recommends targeted action to prevent further extinctions and calls for governments and industry leaders to use these data in water management and policy measures to protect critical species and ecosystems.<\/span>\u00a0<\/span><\/p>\n

\u201cFreshwater landscapes are home to 10% of all known species on Earth and key for billions of people\u2019s safe drinking water, livelihoods, flood control and climate change mitigation, and must be protected for nature and people alike,\u201d said Catherine Sayer, IUCN\u2019s freshwater biodiversity lead and lead author on the paper. \u201cLack of data on freshwater biodiversity can no longer be used as an excuse for inaction.\u201d<\/span>\u00a0<\/span><\/p>\n

\"Odonata_Angola_Neve_River_Lubango_credit
Rivers in Lubango, Angola, are home to hundreds of species of threatened damselflies and dragonfiles. Photo credit: Jens Kipping. Top photo: A school of tilapia. Photo credit: Topiltzin Contreras-<\/span>MacBeath.<\/span><\/em><\/figcaption><\/figure>\n

The study found that the greatest number of threatened species are in ecosystems around Lake Victoria in Central Africa, Lake Titicaca in Bolivia and Peru, Sri Lanka\u2019s Wet Zone and the Western Ghats of India, which are home to some of the highest freshwater biodiversity in the world, including many species found nowhere else on Earth. However, many North American animals are at risk as well, including a large number of crayfish species endemic to Arkansas. All are on the <\/span>IUCN Red List<\/span><\/a>, which tracks at-risk species throughout the world.<\/span>\u00a0<\/span><\/p>\n

The researchers found that pollution, mainly from agriculture and forestry, impacts more than half of all threatened freshwater animals. Freshwater ecosystems are further degraded by land conversion for agricultural use, water extraction and the construction of dams, which also block fish migration routes. Overfishing and the introduction of invasive alien species have had a particularly strong role in driving extinctions.\u00a0<\/span>\u00a0<\/span><\/p>\n

Although the threatened freshwater animals studied tend to live in the same areas as threatened amphibians, birds, mammals and reptiles, they face different threats due to their specific habitats. Conservation action must therefore be targeted to these species.\u00a0<\/span>\u00a0<\/span>\u00a0<\/span><\/p>\n

Crabs, crayfishes and shrimps are at the highest risk of extinction of the groups studied, with 30% threatened, followed by 26% of freshwater fishes and 16% of dragonflies and damselflies.\u00a0<\/span>\u00a0<\/span><\/p>\n

What this means for the Southwest<\/span><\/b>\u00a0<\/span><\/h3>\n

Since there\u2019s less water here, the Southwest already has less biodiversity. It doesn\u2019t take much to threaten Southwest species and their habitats, so a greater proportion are threatened.<\/span>\u00a0<\/span><\/p>\n

\u201cIt\u2019s an area with low freshwater ecosystem density, but the species present tend to be endemic to the pools and rivers and are very prone to threats from things like water abstraction, fragmentation and climate changewhether that be for small springs, of which there are many, or some of the larger rivers like the Colorado that are heavily used by people,\u201d said Harrison, who works in the Free-flowing Rivers Lab in the School of Earth and Sustainability. \u201cPeople living here in the Southwest already know these as issues, but the paper puts this in a global context.\u201d<\/span>\u00a0<\/span><\/p>\n

\"River
River Nidelva at Trondheim in Norway is home to Atlantic salmon and sea trout; the city growing around it illustrates urbanization, habitat change and channelization in the river mouth. Photo credit: Eva B. Thorstad, NINA<\/em><\/figcaption><\/figure>\n

He pointed to the Grand Canyon, which has dozens of small springs that are home to countless species. As endemic species are reduced or become extinct, invasive species often take their place. Researchers have seen adverse effects on these nearby ecosystems.<\/span>\u00a0<\/span><\/p>\n

\u201cThe Grand Canyon is an excellent example of how the change in flow affects not only the fishes but also the macroinvertebrates, which can ultimately result in decreased food sources for birds and declines in bird abundance,\u201d Harrison said. \u201cBut in other rivers across the West, the threats to fish species can also affect subsistence fisheries. The decline in freshwater biodiversity is indeed a harbinger of other, larger effects in terms of water quantity and quality that may be important in terms of water resources.\u201d<\/span>\u00a0<\/span><\/p>\n

\u00a0This global freshwater fauna assessment is the result of more than 20 years of work by more than 1,000 experts from around the world.<\/span>\u00a0<\/span><\/p>\n

\"Northern<\/p>\n

 <\/p>\n

Heidi Toth | NAU Communications
\n(928) 523-8737 | heidi.toth@nau.edu<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

A global study published today in Nature found that one in every four freshwater animal species is at risk of extinction. It\u2019s the largest study of its kind to look at freshwater species like fishes, dragonflies, crabs and shrimps throughout the world.\u00a0 The study, led by the International Union for Conservation of Nature and co-authored…<\/a><\/p>\n","protected":false},"author":59,"featured_media":73640,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[11],"tags":[],"class_list":["post-73600","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research-academics"],"acf":[],"_links":{"self":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts\/73600","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/users\/59"}],"replies":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/comments?post=73600"}],"version-history":[{"count":0,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts\/73600\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/media\/73640"}],"wp:attachment":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/media?parent=73600"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/categories?post=73600"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/tags?post=73600"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}