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IUCN warns at Hawaii conservation meeting that four of six great ape species are at high risk of extinction

September 6, 2016 Leave a comment

The International Union for Conservation of Nature added the Eastern lowland gorilla (Gorilla berengei) to its list of critically endangered species Sunday, raising the number of great ape species that are on very cusp of extinction to four.

The three other critically endangered species of great apes are the Western gorilla (Gorilla gorilla), Bornean orangutan (Pongo pygmaeus), and Sumatran orangutan (Pongo abelii).

There are six species of great apes. The other two species – the chimpanzee (Pan troglodytes) and the bonobo (Pan paniscus) – are endangered.

G. berengei includes two subspecies. One of them, Grauer’s gorilla (G.b. graueri), has experienced a decline in population of nearly 80 percent since 1994. There are about 3,800 individuals left. The other, the Mountain gorilla (G.b. beringei), has a population of about 880 individuals.

“To see the Eastern gorilla – one of our closest cousins – slide towards extinction is truly distressing,” Inger Anderson, IUCN’s director general, said in a statement. “We live in a time of tremendous change and each IUCN Red List update makes us realize just how quickly the global extinction crisis is escalating.”

The great apes are man’s closest relatives in the natural world.

Chimpanzees and bonobos share about 98.8 percent of the human genome. Gorilla genes are about 98.4 percent identical to humans, while the orangutan genome is about 97 percent identical to man.

The IUCN announcement came at its annual conservation congress, a gathering of political leaders, conservationists, and others, in Honolulu, Hawaii.

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New report says world’s largest primate is on fast track to extinction

June 22, 2016 Leave a comment
Grauer's gorilla infant

An infant Grauer’s gorilla is carried on the back of an adult. Photo courtesy Wildlife Conservation Society, photo by A.J. Plumptre.

The eastern lowland gorilla, Earth’s largest primate, is in rapid decline and has seen its population decline by nearly 80 percent since the late 1990s. There are now fewer than 4,000 individuals of the subspecies remaining in the wild.

Such is the bleak conclusion of a report released in April.

Persistent war in the animal’s home range, which is limited to a forested region in eastern Democratic Republic of Congo, is the leading culprit for the rapid extermination of the great ape species.

“Since 1996, the entire range of Grauer’s gorilla has been consumed in conflict,” the report said. “This has resulted in an almost complete breakdown in government control, including wildlife protection activities.”

Grauer's gorilla - courtesy FFI, photo by Stuart Nixon

Image of adult Grauer’s gorilla courtesy Fauna & Flora International, photo by Stuart Nixon.

The civil war in DRC began in in the aftermath of the 1994 genocide event in Rwanda. Hundreds of thousands of refugees streamed into DRC. Upon arrival, they engaged in deforestation in the eastern region of the country. The inflow of Rwandans refugees also helped set off a conflict that killed millions of people between 1996-2003.

Although the war is over, the militias who participated in it have not disappeared. They control areas in the eastern DRC that are the only habitat for Grauer’s gorillas and, in that territory, they tolerate mining and engage in bushmeat hunting.

The mining, which is done on a small scale and often illegally, is aimed at extracting minerals used in the production of elecronic devices such as cellular phones, laptop computers, and gaming consoles.

Grauer’s gorillas, as well as chimpanzees, are hunted by the militia soldiers to feed the miners, which fund them, and themselves. Although protected by law, the large size of a Grauer’s gorilla means it can provide enough meat to feed multiple humans. Because the animal moves in a troop through its forested habitat, hunters can take multiple gorillas and feed even more humans.

Disarming the militias and imposing legal controls on the small-scale mining within Grauer’s gorilla habitat is a crucial step toward assuring the subspecies’ survival, said the report’s authors.

“Significantly greater efforts must be made for the government to regain control of this region of DRC,” Andrew Plumptre, a wildlife biologist with Wildlife Conservation Society and the lead author of the report, said. “In particular, the government needs to quickly establish Reserve des Gorilles de Punia and the Itombwe Preserve, and reinforce Kahuzi-Biega National Park efforts, which have community support, and to establish strong communication between [Institut Congolais pour la Conservation de la Nature] and the DRC military to tackle armed militias that control mining camps in Grauer’s gorilla heartland.”

The report also concluded that agriculture, poaching for body parts, and “socio-economic depression from over a decade of civil war” are contributing to the rapid decline of Grauer’s gorilla and other plant and animal species.

Stuart Nixon, a wildlife biologist at the United Kingdom’s Chester Zoo and a co-author of the report, emphasized that a speedy government response to these stressors is vital.

“Unless greater investment and effort is made, we face the very real threat that this incredible primate will disappear from many parts of its range in the next five years,” he said.

The most recent prior population survey of Gorilla beringei graueri occurred during the mid-1990s. Researchers concluded that a population of about 17,000 individuals remained at that time.

The current conflict is not the first occasion in which Grauer’s gorillas have suffered extensive losses at the hands of humans.

During the 1960s and 1970s many individuals were killed as grassland areas of their range were converted to agriculture and farmers used shotguns provided by the government of Zaire to kill the gorillas.

Gorilla beringei graueri is one of four gorilla subspecies. Like individuals of the other three subspecies, Grauer’s gorillas live in groups. They are thought to organize themselves into harem-like assemblages that include two males. A female matures at about eight years of age, while a male reaches full development after about 12 years.

A full-grown male Grauer’s gorilla can weigh up to 400 pounds.

Both females and males leave the group at maturity, with male Grauer’s gorillas staying together until each can attract females and form new groups. Females join a group or ally themselves with a single adult male.

Also known as the eastern lowland gorilla, Grauer’s gorilla is closely related to the smaller western lowland gorilla (Gorilla gorilla gorilla) that is endemic to central African forests.

The report’s authors recommend that the status of Gorilla beringei graueri be downgraded from endangered to critically endangered by the International Union for the Conservation of Nature.

A species listed as “critically endangered” is just one step, on the IUCN hierarchy of classification, from extinction in the wild.

The report was published by the Wildlife Conservation Society, Flora and Fauna International and the Congolese Institute for the Conservation of Nature.

 

Bee learning ability slowed by pesticides, study finds

April 28, 2016 Leave a comment
Bumble bee - courtesy Wikimedia

This image shows a bumble bee loaded with pollen. Image courtesy Wikimedia.

Bees exposed to pesticides might have a harder time learning how to pollinate flowers than those who are not exposed to the substances, a new study suggests.

The paper, which was published in the March 14 edition of Functional Ecology, is the first to show that neonicotinoids, a class of pesticides that is now commonly used to protect a variety of agricultural crops, may impact the ability of individual bees to forage for nectars and pollen. It examined the impact of a compound called thiamethoxam on bumblebees.

“What we found is that bees exposed to pesticide initially collected more pollen, but it took them more visits to flowers to properly ‘learn’ this behavior,” Dr. Dara Anne Stanley, the lead author of the paper and a researcher at the University of KwaZulu-Natal in South Africa, said. “Control bees collected less pollen, but learned the behavior properly after visits to less flowers. Therefore control bees may be investing more time in learning this behavior properly.”

That result is consistent with the findings of other recent studies. For example, a paper published last year showed that bumblebees exposed to pesticides suffer memory loss. Another paper published in 2015 demonstrated that bumblebee colonies that encounter neonicotinoids tend to forage for pollen less than those colonies that do not come into contact with the compounds.

Neonicotinoids appear to target the area of a bee’s brain that governs the insect’s behavior.

“Neonicotinoid pesticides in particular target a region of the insect brain called the nicotinic acetylcholinase receptors (nAChRs) where they target cholinergic signaling by inhibiting acetylcholinesterase,” Stanley said in an e-mail message. “As the nAChRs have been associated with behavior in insects, in particular learning and memory, this means these pesticides at sub-lethal doses have the potential to cause changes in insect behavior.”

The term cholinergic signaling refers to the movement of neurotransmitters in an organism’s nervous system. Those compounds carry information across synapses.

If the pesticide is used near a bee colony, then its impacts on the ability of individual bees to obtain pollen could negatively affect the whole colony.

“As bees in particular display a range of sophisticated behaviors involved in navigation, foraging etc, these pesticides have the potential to effect foraging success and ultimately colony health,” Stanley said.

That may be less of a worry for honeybees, which live in large colonies. Stanley explained that a recent study conducted in Sweden indicated that honeybees are affected by exposure to pesticide-treated crops less rapidly than bumble bees.

“Honeybee colonies are extremely large with thousands of workers, and therefore the effects of pesticides on individuals would have to be very strong to see any impacts on the whole colony, and if there are impacts it could take many years to become apparent,” she said. “However, bumblebee colonies are much smaller and therefore any impacts on individuals are likely to be much more influential on the colony as a whole. When it comes to solitary bees, each individual female builds her own nest, so they are likely to be even more susceptible to any behavioral effects on individuals.”

While sale of neonicotinoids are now worth about $2.6 billion per year to manufacturers, the substances are thought to be dangerous to many other organisms. A series of papers published in 2014 indicated that they “exhibit very high toxicity” to many invertebrates and that some bird and fish species are especially vulnerable to harm caused by the use of neonicotinoids.

305 million year-old ancestor of spiders is identified

April 28, 2016 Leave a comment
Early arachnid

Idmonarachne brasieri lived about 305 million years ago. Image courtesy University of Manchester.

Paleontologists have identified an ancestor of modern spiders that lived before the dinosaurs began their long domination of the planet.

The arachnid’s fossil remains were found during the mid-1970s in Europe embedded in an iron-rich mineral, siderite, that is difficult for x-rays to penetrate. Researchers used a synchotron, which emits more powerful x-rays, to identify the organism.

Named Idmonarachne brasieri, the organism was likely a member of a group of arachnids called uraraneids. These animals lacked spinarets, which modern spiders use to spin webs, and instead would have discharged silk in sheets.

“Our new fossil occupies a key position in the evolution of spiders,” Dr. Russell Garwood of the University of Manchester, the lead author of a paper documenting the discovery, said. “It isn’t a true spider, but has given us new information regarding the order in which the bits of the anatomy we associate with spiders appeared as the group evolved.”

Scientists know little of the origin of spiders and the evolutionary path by which such anatomical features as spinarets formed is not well understood.

The paper appears in the March 30 edition of Proceedings of the Royal Society B.

 

Chimps engage in stone-throwing pattern, study says

March 3, 2016 Leave a comment

Anyone who has seen chimpanzees in a zoo know that the African primate has a tendency to throw things at people: Rocks, for example, or poop.

Now research shows that Pan troglodytes also likes to throw rocks at trees.

stones under trees - courtesy MPI-EVA, PanAf-Chimbo Foundation

This image shows stones accumulated at the base of an African tree. They were thrown by chimpanzees. Photo courtesy Max Planck Institute, Institute for Evolutionary Anthropology; Pan-African Program: The Cultured Chimpanzee; Chimbo Foundation.

Scientists collected data at 39 sites in four African countries for 14-17 months since 2010. They used non-invasive methods, including camera traps, to demonstrate that chimpanzees engage in a behavior that involves picking up stones near or in a tree and then launching them at the tree.

The behavior is not limited to one or the other gender. The researchers concluded that males most commonly engaged in it, but females also throw rocks at trees. So do juveniles.

It is not clear why chimpanzees throw rocks at trees.

One possibility proposed by the researchers is that it is a form of male dominance display. Another is that it is an expression of chimpanzee culture.

“As the stone accumulation behavior does not seem to be linked to either the abundance of stones or the availability of suitable trees in an area, it is likely that it has some cultural elements,” Christophe Boesch, director of the Department of Primatology at the Max Planck Institute for Evolutionary Anthropology, said.

Chimpanzees are known to use tools such as sticks to extract fish or ants or to remove honey from hives. They also communicate with each other, including by drumming on tree roots and by vocalizing pant hoots.

Pan troglodytes is Homo sapiens‘ closest relative. An individual human’s genome is 99 percent similar to that of a chimpanzee.

Social animals who live in groups that range in size from as few as five to as many as about 150 individuals, chimpanzees are omnivorous. They are known to eat fruit, bark, leaves, and stems, as well as other mammals. Colobus monkeys are a particularly common prey animal for chimpanzees.

Pan troglodytes is an endangered species under American law. Their population is thought to have declined from more than a million at the turn of the twentieth century to as few as about 200,000-300,000 individuals at present, according to FWS.

AP0040-03

Chimpanzees, like the mother and infant pictured here, are humans’ closest living relatives. Flo, the female adult in the image, and her infant Flint were made famous when the primatologist Jane Goodall wrote of her research involving the two chimpanzees. Photo courtesy Jane Goodall Institute.

The new paper appears in the Feb. 29 edition of Nature Scientific Reports.

Video shows only known wild jaguar in U.S.

February 27, 2016 1 comment

An environmental advocacy organization released a video earlier this month that shows a jaguar wandering in Arizona’s Santa Rita Mountains, near Tucson. The big cat is the only one if its kind known to live in the wild in this country.

Jaguars (Panthera onca) were once relatively common in the American Southwest and had a range that extended all the way to southern Argentina.  A 1989 scientific paper concluded that hunters extirpated the big cat from the United States.

In 1997 the U.S. Fish & Wildlife Service designated the species as endangered within the country and in Mexico, Central America, and  South America. The International Union for Conservation of Nature considers jaguars to be near-threatened throughout their worldwide range.

Panthera onca is also protected by an international treaty, the Convention on International Trade in Endangered Species of Wild Fauna and Flora, that prohibits exploitation of the animal for commercial purposes.

Jaguars are smaller than lions (Panthera leo) and tigers (Panthera tigris). Females generally  reach a mass of about 75 kilograms, while males usually grow to a size as large as about 95 kilograms. Some larger specimens have been reported.

Jaguars range far, if prey is not abundant, and eat a varied diet. Crepuscular in their hunting habits, they are known to eat more than 85 other species, including armadillos, birds, caimans, capybaras, deer, fish, pacas, peccaries (javelinas), and turtles.

Of all the big cats (lions, tigers, leopards, and snow leopards are the others), the jaguar is the least likely to attack a man.

Known in the Spanish language as “el tigre” the presence of the big cat near a major American city may be bringing a smile to some faces in southern Arizona.

“Just knowing that this amazing cat is right out there, just 25 miles from downtown Tucson, is a big thrill,” Randy Serraglio, a conservation advocate with the Center for Biological Diversity, said.

Smithsonian museum to display last passenger pigeon

August 9, 2014 Leave a comment

As the one hundredth anniversary of the passenger pigeon’s extinction approaches, the National Museum of Natural History is giving Americans the chance to see the last individual of the species.

The stuffed remains of Martha, who died at the Cincinnati Zoo on Sept. 1, 1914, will be posed on a branch for the display.

Passenger pigeons once numbered in the billions. At one time it was the most abundant bird on Earth and accounted for at least one quarter of all individual birds in North America.

Ectopistes migratorius was a fast flyer. One scientist estimated in 2002 that the bird could travel at a velocity exceeding 60 miles per hour. Passenger pigeons could also travel long distances, migrating in huge flocks that routinely numbered in the millions or more.

The display at the Smithsonian Institution museum in Washington, DC will also include specimens of the heath hen and the great auk, other notable examples of bird species driven to extinction by humanity.

This website provides information about the exhibition, entitled Once There Were Billions: Vanished Birds of North America.

Categories: biodiversity, biology, wildlife
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