red list

Thousands of species threatened

January 24, 2024 By EarthWise Leave a Comment

The International Union for the Conservation of Nature is an organization working in the field of nature conservation and sustainable use of natural resources. The IUCN has been around for nearly 75 years and is the global authority on the status of the natural world and the measures needed to safeguard it.

In its latest accounting, the IUCN has determined that more than 44,000 species worldwide are threatened with extinction. Among them, nearly 7,000 face an immediate threat from climate change.

The organization tracks 157,000 species to compile its Red List and found that climate change poses a growing threat to many kinds of wildlife. At particular risk are freshwater fish including Atlantic salmon, which are now classified as “Near Threatened.”

In all, about 25% of freshwater fish are threatened with extinction. This is in part driven by rising sea levels which causes saltwater to be driven up into rivers. Some 41% of amphibians are threatened with extinction, in part due to more intense heat and drought. Many populations of green turtles are at risk of extinction because of rising temperatures lowering hatch rates and rising sea levels flooding nests.

It isn’t just animals at risk. For example, big leaf mahogany, one of the world’s most commercially sought-after timber trees, has moved from Vulnerable to Endangered on IUCN’s Red List. Thousands of trees have been added to the Red List, many of which are timber species, and some are keystone species in forests.

Endangered and threatened species are often irreplaceable parts of ecosystems which provide humans with many services that only the natural world can.

**********

Web Links

More Than 44,000 Species Now Threatened With Extinction

Photo, posted November 22, 2010, courtesy of E. Peter Steenstra/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Assessing The Planet’s Most Unique Birds | Earth Wise

January 11, 2023 By EarthWise Leave a Comment

Birds come in a huge variety of shapes, sizes and plumages. The physical attributes of birds are adaptations that have taken countless millennia to develop, and physical attributes are closely related to the roles birds play in their environment.

According to a new study led by researchers from the University College London in the U.K., bird species with extreme or uncommon combinations of traits have the highest risk of extinction. Losing these bird species and the unique roles they play in the environment, including seed dispersal, pollination and predation, could have severe consequences on the health of ecosystems.

In the study, which was recently published in the British Ecological Society journal Functional Ecology, the researchers analyzed the extinction risk and physical attributes of 99% of all living bird species. The research team used a dataset of measurements collected from living birds and museum specimens. The measurements included things like beak size and shape, and the length of wings, tails and legs. The researchers combined this data with extinction risk, and then ran simulations to see what would happen if the most threatened birds were to go extinct.

Some of the bird species that are both most unique and most threatened include the Christmas Frigatebird and the Bristle-thighed Curlew. Kiwis were excluded from the study because the researchers viewed them as extreme morphological outliers.

While most unique birds were also classified as threatened on the Red List, the research was unable to show what links uniqueness in birds to extinction risk

The research team warns that if more isn’t done to protect these threatened species and avoid extinctions, the functioning of ecosystems will be dramatically disrupted.

*********

Web Links

Planet’s most unique birds at higher risk of extinction

Photo, posted June 25, 2012, courtesy of Kristine Sowl / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Future Of Animals

June 12, 2019 By EarthWise Leave a Comment

Researchers at the University of Southampton have forecast a global shift towards smaller birds and mammals over the next century.

According to the research team, small, fast-lived, highly fertile, and insect-eating animals, which can thrive in all sorts of habitats, will predominate in the future. Rodents and songbirds are examples of the so-called ‘winners.’ Less adaptable, slow-lived species, requiring specialist habitats, will be more likely to face extinction. Among the so-called ‘losers’ are the black rhino and the tawny eagle.

The researchers focused on more than 15,000 living mammals and birds and considered the following five characteristics: body mass, breadth of habitat, diet, litter or clutch size, and length of time between generations. Using this data and data from the IUCN’s Red List of Threatened Species, the researchers used modern statistical tools to project and evaluate the loss of biodiversity.

The study, which was recently published in the journal Nature Communications, predicts that the average body mass of mammals will collectively decline by 25% over just the next 100 years. Over the past 130,000 years, the average body size of mammals only declined 14%.

This substantial downsizing of animals is forecasted to occur due to the effects of ecological change. But, according to the study’s lead author, the loss of these species, which perform unique functions within the global ecosystem, may ironically wind up being a driver of change as well.

The researchers hope future studies will further explore the long-term effects of species extinction on habitats and ecosystems.

**********