Alien species are primary cause of recent global extinctions

Alien species are the main driver of recent extinctions in both animals and plants, according to a new study by UCL researchers.

Date:  March 3, 2019

Source:  University College London

Alien species are the main driver of recent extinctions in both animals and plants, according to a new study by UCL researchers.

They found that since 1500, alien species have been solely responsible for 126 extinctions, 13% of the total number studied.

Of 953 global extinctions, 300 happened in some part because of alien species, and of those 300, 42% had alien species alone listed as the cause of their demise.

The study, published today in Frontiers in Ecology and the Environment, used data from the 2017 IUCN Red List on the total numbers of species that are considered to have gone extinct globally since 1500.

In total, 261 out of 782 animal species (33.4%) and 39 out of 153 plant species (25.5%) listed aliens as one of their extinction drivers. In contrast, native species impacts were associated with only 2.7% of animal extinctions and 4.6% of plant extinctions.

"Some people have suggested that aliens are no more likely than native species to cause species to disappear in the current global extinction crisis, but our analysis shows that aliens are much more of a problem in this regard," said lead researcher Professor Tim Blackburn (UCL Biosciences).

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Unprecedented wave of large-mammal extinctions linked to prehistoric humans

Date:  April 19, 2018

Source:  University of Nebraska-Lincoln

Summary:

Homo sapiens, Neanderthals and other recent human relatives may have begun hunting large mammal species down to size -- by way of extinction -- at least 90,000 years earlier than previously thought, according to a new study. The magnitude and scale of the extinction wave surpassed any other recorded during the last 66 million years, according to the study.

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Species make comeback 30 years after rainforest devastation

Date:  February 28, 2018

Source:  University of Salford

Summary:

Rainforest loss is fueling a tsunami of tropical species extinctions. However, not all is doom and gloom.

A new study, conducted in the Brazilian Amazon, suggests that ecological cataclysms prompted by the fragmentation of the forest can be reverted by the regeneration of secondary forests, offering a beacon of hope for tropical forest biodiversity across the world.

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Decade-long plan to halt native animal extinctions to be led by conservationists

Bush Heritage Australia will lead initiative involving 50 scientists that aims to rescue dozens of species from the brink

Oliver Milman

Wednesday 8 April 2015 05.30 BSTLast modified on Wednesday 8 April 201505.33 BST

A 10-year plan to tackle the rapid extinction rate of Australian animals has been launched, with scientists from across the country collaborating on ways to deal with the biodiversity loss.

Australia is spearheading the initiative, that will involve 50 scientists from 15 universities working on 55 projects to find solutions to the alarming decline of native Australian animals.

Australia has the worst rate of mammal extinctions in the world, losing 29 species over the past 200 years, with a further 56, or one in five remaining species, at risk of being wiped out.

This crisis also extends beyond mammals, with dozens of bird, plant, fish, reptile and amphibian species listed as critically endangered by the federal government.

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Species that have become extinct in England since the 1980s

New list of recently extinct creatures

Creatures like the wildcat and tortoise butterfly have gone the way of the dodo and are now extinct.

A new list of extinct species in England has been released which shows animals and plants have died out at a rate of more than two species a year for the past 200 years.

The Species Recovery Trust said 421 beasts, birds, bugs and plants have disappeared from the countryside. It has published an online database called The Lost Life Project about extinct creatures since 1800.

This gallery takes a look at the species which have died out since the 1980s...

Black-backed meadow ant

Scientific name: Formica pratensis

Home: around Bournemouth and Wareham in Dorset

Extinct: 1988

Reasons: urban development and inappropriate land management

Click the gallery above to see more...

Find gallery here

Marsupial Extinctions: Don't Blame the Dingoes (Op-Ed)

By Christopher Johnson Barry W. Brook, Corey Bradshaw, and Thomas Prowse | January 14, 2014 

This article was originally published at The Conversation.The publication contributed the article to LiveScience's Expert Voices: Op-Ed & Insights.

The humble dingo has become something of a scapegoat since its arrival in Australia just 4000 years ago. It is widely blamed for the disappearance of thylacines (also known as Tasmanian tigers) and devils from the mainland - an event that left Tasmania as their sole refuge.

The hypothesis is that when dingoes spread through the mainland, they were smarter, faster and more versatile predators than their marsupial counterparts, who lost the battle for survival.

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Extinctions of Large Animals Sever the Earth's 'Nutrient Arteries'

Aug. 13, 2013 — A new study has demonstrated that large animals have acted as carriers of key nutrients to plants and animals over thousands of years and on continental scales.

The paper in the advance online publication of the journal Nature Geoscience explains that vital nutrients are contained in the dung and bodies of big animals. As they eat and move more than small animals, they have a particularly important role in transporting nutrients into areas where the soil is otherwise infertile.

In the study, the researchers use a new mathematical model to calculate the effect of mass extinctions of big animals around 12,000 years ago, focusing on a case study of the Amazon forest. They estimate that extinctions back then reduced the dispersal of phosphorus in the Amazon by 98%, with far-reaching environmental consequences that remain to this day. The model also enables them to forecast the likely environmental effects of the extinction of large animals currently under threat in Africa and Asian forests.

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Lizard, skink and fish declared extinct as porpoise and snails cling to the edge

Nearly 5000 species added to Red List

July 2013. The latest update of The IUCN Red List of Threatened Species shows worrying declines for freshwater shrimps, cone snails and the Yangtze Finless Porpoise. The Santa Cruz Pupfish, a lizard known as the Cape Verde Giant Skink and a species of freshwater shrimp have been declared Extinct.

With this update, 4,807 species have been added to The IUCN Red List bringing the total of assessed species to 70,294, of which 20,934 are threatened with extinction.

Yangtze Finless Porpoise - Critically Endangered

The Yangtze Finless Porpoise, one of the world's few remaining freshwater cetaceans, has been declining by more than 5% annually since the 1980s and it has been assessed as Critically Endangered. Increasing threats to these porpoises include illegal fishing, intense vessel traffic, sand mining and pollution.

Second river dolphin to become extinct in China?

Prof. Jonathan Baillie, Director of Conservation Programmes at ZSL said: "The Baiji (a unique freshwater dolphin) only recently went extinct on the Yangtze River. If we now lose the Yangtze Finless Porpoise, future generations will undoubtedly wonder if we were ignorant, incompetent or both."

White-lipped peccary

The White-lipped Peccary (Tayassu pecari) - a member of the pig family found in Central and South America - has declined by 89% in Costa Rica and 84% in Mexico and Guatemala and is now listed as Vulnerable. Hunting and habitat loss explain some of the decline but many cases of mysterious disappearance of the species have been documented in several regions with disease suspected to be the primary cause.

Continued: http://www.wildlifeextra.com/go/news/iucn-extinct013.html

Lions extinct in 25 African countries & populations in more trouble than previously thought

Lions virtually extinct in 10 countries

January 2013. LionAid, the charity dedicated to lion conservation, has made a new assessment of remaining lion populations on the African continent. The assessment reveals a catastrophic decline from previously held extrapolated estimates.

Just 15,000 lions left in Africa
LionAid estimates that only 15,244 lions remain on the entire continent with only 645-795 wild lions remaining in western and central Africa and 14,450 wild lions remaining in eastern and southern Africa.
Just 5 populations are likely to number over 1,000 lions - located in: Tanzania/Kenya (3); South Africa (1); Botswana/Zimbabwe (1). LionAid believes that lion populations have declined for a variety of reasons including habitat loss; destruction of natural prey due to poaching for households and the bush meat trade; human/livestock/predator conflict; impact of diseases like canine distemper, bovine tuberculosis and feline immunodeficiency virus; illegal wildlife trade in lion products and live animals, and excessive trophy hunting.

West Africa lion on the verge of extinction
Western and central African lions are highly genetically distinct from their eastern and southern African counterparts - in fact analyses have shown that western and central African lions are more closely related to remaining lions in India. Their alarming decline has not received the highly dedicated corrective conservation attention needed from any major conservation agency. These lions could be extinct within the next 5 years, especially as they currently exist in small and highly isolated populations. Lions are thought to survive in just 5 West African countries, Benin, Guinea, Mali, Nigeria and Senegal, and 2 in Central Africa, Cameroon & Democratic Republic of the Congo, having become extinct in Algeria, Cote d'Ivoire, Equatorial Guinea, Gabon, Gambia, Ghana, Guinea Bissau, Liberia, Libya, Mauritania, Morocco, Niger, Republic of the Congo, Sierra Leone, Togo & Tunisia.


Continued: http://www.wildlifeextra.com/go/news/extinct-lions.html

2012’s Noteworthy Species-A roundup of species that made their scientific debut in 2012, and a few that said goodbye as well – via Herp Digest

By Sabrina Richards | December 18, 2012, The Scientist

The world's tiniest chameleon, Brookesia micra.FRANK GLAW and JÖRN KÖHLERResearchers described roughly 15,000 to 18,000 new species in 2012, making choosing the most noteworthy a monstrous task. “[It’s] worse than asking me which of my children is my favorite,” quipped Quentin Wheeler, an entomologist at Arizona State University, in an email to The Scientist. Wheeler and his colleagues at the International Institute for Species Exploration will eventually publish a top ten list of this year’s new species, but the ranking criteria “are as diverse as the species themselves,” he said.

Some of this year’s new species were encountered by researchers deep in the field. Others were recognized from museum specimens—long after the “new” species themselves had gone extinct, noted Benoît Fontaine, a conservation biologist at the Muséum National d'Histoire Naturelle in Paris. Even so, cataloging new species is an important task, said Fontaine. “We know only small part of extant biodiversity,” he noted. “It’s the tip of iceberg.”

In celebration of biodiversity, here a few of 2012’s most exciting new species, and a fond farewell to a few more.

Human cousins

One of the newly identified species of slow loris, Nycticebus kayan. CH'IEN C. LEE The discovery of primate species that are new to science is quite rare, but this year researchers described at least two. Researchers from the United States and United Kingdom stumbled across a previously unrecognized species of slow loris (Nycticebus kayan), small nocturnal primates related to lemurs, while surveying slow lorises in Borneo and the Philippines. Like its relatives, the new species has endearingly wide eyes and small statures—but extremely poisonous bites. Slow lorises lick a toxin-secreting gland on their arm to create venomous saliva, which they use to deter predators. Unfortunately, slow lorises are popular in the pet trade. To keep future owners safe, their captors often remove the loris’s fangs, but this usually ends in the primate’s death, as they can no longer feed properly.

A lesula monkey, Cercopithecus lomamiensis. JOHN HART The sleepy-eyed lesula (Cercopithecus lomamiensis) was also officially added to the books in 2012. Well-known to locals near its Congo forest home, the lesula is only the second monkey species in its genus. The animal is light in color, making it easily distinguishable from its closest relations, the dark-furred owl-faced monkeys. John Hart of the Lukuru Wildlife Research Foundation and the Yale Peabody Museum of Natural History, who described the species in PLOS ONE, said the first lesula example his team studied was being kept as a pet by a schoolteacher’s daughter. When investigating the nearby forest, the group “expected to find something unusual, maybe a range extension [of a known species],” Hart explained. “But we were never prepared to find a new species.”

Though humans don’t farm or mine the forest, lesulas are threatened by the bush meat trade. Having depleted richer sources of bushmeat, hunters will travel “hundreds of kilometers” to hunt monkeys, Hart said. Smoked bushmeat is then sold in urban centers, where many people have no other protein options. But recognition of the lesula as a new species may aid conservation efforts, he added.

Distinctive genitalia

Juvenile Brookesia micra. FRANK GLAW and JÖRN KÖHLERFor some animal species, their genitalia are the best way to identify them. Scientists described a new species (Phallostethus cuulong), belonging to the priapum fish family, whose penises erupt from their chins. This bizarre method of identification is the best for Madagascar’s miniature Malagasy leaf chameleons, which can be distinguished by subtle differences in the shape of their hempenes, the reproductive organs held inside their body until mating. But the newest—and tiniest—member, called Brookesia micra, can be easily identified without getting too intimate. B. micra is about an inch long with “a very, very short tail. The tail has even sometimes a reddish color. It’s totally unique,” said Miguel Vences, a zoologist at the Technical University of Braunschweig in Germany, who led the study identifying the miniscule critter.

Teeny tiny fly

World's tiniest fly, Euryplatea nanaknihali. INNA-MARIE STRAZHNIK This year also saw the discovery of the world’s tiniest fly, identified by entomologist Brian Brown at the Natural History Museum of Los Angeles County. Nearly microscopic at less than half a millimeter in length, Euryplatea nanaknihali—named for a young entomology enthusiast who often visits Brown’s museum—belongs to a group of flies that parasitize ants. Brown, who first spotted the fly in an insect trap in Thailand, knew at first sight that E. nanaknihali was unusual. It is a “very odd” looking fly, said Brown, having “a rounded teardrop shape that makes it hard to grab, and short stubby broad wings a smoky grey in color. . . . Most people would probably think it’s a beetle.”

The tiny fly belongs to a group that lays their eggs in an ant’s head. As the fly larvae develop, they feed on the ant’s tissue until “the ant’s head falls off, sometimes as its body is still walking around,” Brown said.

New lion on the block

Addis Ababa lion. JOERG JUNHOLD and KLAUS EULENBERGER, LEIPZIG ZOO In another boon for biodiversity, researchers confirmed this year that a population of Ethiopian lions with a unique dark mane are indeed genetically distinct from other lions in other areas. Descended from a founder population collected by Emperor Haile Selassie in 1948, the lions are known to scientists from the Addis Ababa Zoo, though reports of dark-maned lions in the wild also exist.

Researchers used the sequence of the mitochondrial cytochrome b gene and various microsatellites to ascertain that the dark-maned lions are genetically separate from other lions. The news has already given the lions a boost, said Susann Bruche, a biologist at Imperial College London and first author of the paper. Zoo officials have raised money for a better lion enclosure, based on natural habitats, which will give the lions more space to breed and maintain their population.

A few goodbyes

Copper-striped blue-tailed skink. CHRIS BROWN, USGS The International Union for Conservation of Nature, which puts out the Red List assessing species’ extinction risks, lists 795 species as extinct. But each year, often due to human encroachment, that list grows. Hawaii, the poster child for the havoc wreaked by invasive species—and the heroic efforts to combat them—announced the local extinction of the copper-striped blue-tailed skink this year, possibly due to torment by predatory ants. Luckily, blue-tailed skink populations persist on other Pacific Islands.

Japan announced the extinction of the Japanese river otter, an iconic creature not seen for more than 30 years. Japan’s Ministry of Environment also declared several other species extinct, including the least horseshoe bat.

Lonesome George. WIKIPEDIA, putnymark And finally, the Galápagos’s Lonesome George, the long-lived Pinta Island giant tortoise believed to be the last of his kind, died this summer. More than 100 years old, Lonesome George was introduced to several female tortoises in hopes of producing hybrids, but the eggs laid never hatched. But amidst the sorrow of his passing, some scientists retain hope. New work by evolutionary biologist Adalgisa Caccone at Yale University suggests that a few Pinta Island tortoises may still exist—and be successfully hybridizing with the locals—at Volcano Wolf on nearby Isabela Island. Caccone and her colleagues compared the DNA of more than 1,600 Volcano Wolf tortoises to a DNA database of extinct tortoises collected from museum specimens, and discovered that 17, including some juveniles, had DNA from C. abingdoni ancestors.

Study Demonstrates That One Extinction Leads to Another

ScienceDaily (Aug. 14, 2012) — When a carnivore becomes extinct, other predatory species could soon follow, according to new research. Scientists have previously put forward this theory, but a University of Exeter team has now carried out the first experiment to prove it.

Published August 15, 2012 in the Royal Society journal Biology Letters, the study shows how the demise of one carnivore species can indirectly cause another to become extinct. The University of Exeter team believes any extinction can create a ripple effect across a food web, with far-reaching consequences for many other animals.

The research adds weight to growing evidence that a 'single species' approach to conservation, for example in fisheries management, is misguided. Instead the focus needs to be holistic, encompassing species across an entire ecosystem.

The researchers bred two species of parasitic wasps, along with the two types of aphids on which each wasp exclusively feeds. They set up tanks with different combinations of the species and observed them for eight weeks. In tanks that did not include the first species of wasp, the second went extinct within a few generations. In tanks in which they co-existed, both wasp species thrived.

Continued:  http://www.sciencedaily.com/releases/2012/08/120814213500.htm

Environmental Concerns Increasing Infectious Disease in Amphibians, Other Animals

ScienceDaily (July 18, 2012) — Climate change, habitat destruction, pollution and invasive species are all involved in the global crisis of amphibian declines and extinctions, researchers suggest in a new analysis, but increasingly these forces are causing actual mortality in the form of infectious disease.

Amphibians are now, and always have been hosts for a wide range of infectious organisms, including viruses, bacteria and fungi, scientists said in a review published inPhilosophical Transactions of the Royal Society B.

But in recent decades, disease seems to have taken a more prominent role in causing mortality. Because of multiple stresses, many induced by humans, amphibians now succumb to diseases they may historically have been better able to resist or tolerate.

"There's more and more evidence of the role of disease in the biodiversity crisis, in both amphibians and other types of animals," said Andrew Blaustein, a distinguished professor of zoology at Oregon State University and author of the recent analysis.

Continued:  http://www.sciencedaily.com/releases/2012/07/120718143607.htm