Jeanna Bryner, LiveScience.com Yahoo News 5 Aug 08;
A new tally of lowland gorillas has found massive and surprising numbers of these African primates alive and well in the Republic of Congo, Wildlife Conservation Society scientists announced.
The new census puts the number of western lowland gorillas (called great apes, along with chimpanzees, bonobos and orangutans) within two adjacent areas in the northern part of the Congo at 125,000 individuals, including infant gorillas. The results were announced today during a press conference at the International Primatological Society Congress in Edinburgh, Scotland.
Previous estimates from the 1980s placed the entire population of western lowland gorillas, which live in seven Central African nations, at fewer than 100,000 individuals. Sine then, scientists thought the number would've at least halved due to hunting and disease.
Western lowland gorillas are one of four recognized gorilla sub-species, along with mountain gorillas, eastern lowland gorillas and Cross River gorillas. While the eastern lowland gorilla is considered endangered by the International Union for Conservation of Nature (IUCN), the others are labeled "critically endangered," which means the group faces an extremely high risk of extinction in the wild.
Counting apes
With partial funding from admission fees to the Bronx Zoo's Congo Gorilla Forest exhibit, WCS researchers combed rainforests and isolated swamps to count gorilla "nests," which gorillas construct out of leaves and branches each night for a sleeping area.
The researchers estimate 73,000 came from the Ntokou-Pikounda region and another 52,000 from the Ndoki-Likouala landscape, which includes a previously unknown population of nearly 6,000 gorillas living in an isolated swamp.
"We knew from our own observations that there were a lot of gorillas out there, but we had no idea there were so many," said Emma Stokes, who led the survey efforts in Ndoki-Likouala. "We hope that the results of this survey will allow us to work with the Congolese government to establish and protect the new Ntokou-Pikounda protected area."
Ape conservation
The researchers attribute the high numbers to successful long-term conservation tactics in the area; the remoteness and inaccessibility of the key gorilla hideouts; and a food-rich habitat.
"These figures show that northern Republic of Congo contains the mother lode of gorillas," said Steven E. Sanderson, WCS president and CEO. "It also shows that conservation in the Republic of Congo is working."
For instance, WCS has worked with the Republic of Congo government in the northern area of the country for nearly 20 years. There, the cooperative effort helped to establish the Nouabale-Ndoki National Park and manage the Lac Tele Community Reserve, while working with logging companies outside of protected areas to reduce illegal hunting.
Congo Gorilla Bonanza Doubles Population Estimates
PlanetArk 6 Aug 08;
WASHINGTON - A crowd of gorillas has survived in the northern part of the Republic of Congo -- so many that environmentalists can double population estimates, has survived in the northern part of the Republic of Congo -- so many that environmentalists can double population estimates, according to a report released on Tuesday.
A new census tallied more than 125,000 western lowland gorillas in an 18,000-square-mile (47,000-square-kilometer) area, the Wildlife Conservation Society reported.
Estimates from the 1980s had suggested fewer than 100,000 of the great apes had survived and many experts believed these numbers had been cut nearly in half by disease and hunting.
"These figures show that northern Republic of Congo contains the mother lode of gorillas," Steven Sanderson, president and chief executive officer of the Wildlife Conservation Society, said in a statement.
"It also shows that conservation in the Republic of Congo is working. This discovery should be a rallying cry for the world that we can protect other vulnerable and endangered species, whether they be gorillas in Africa, tigers in India, or lemurs in Madagascar."
The group released its findings at a meeting of the International Primatological Society Congress in Edinburgh, Scotland.
Researchers counted nests made by gorillas in rainforests and isolated swamps. Gorillas make fresh nests every night.
Western lowland gorillas are one of four recognized gorilla sub-species, which also include mountain gorillas, eastern lowland gorillas, and Cross River gorillas.
All are classified as "critically endangered" by the International Union for Conservation of Nature or IUCN, except eastern lowland gorillas, which are endangered.
Another report from the IUCN shows nearly half the world's monkeys and apes are facing a worsening threat of extinction because of deforestation and hunting for "bushmeat".
They found that 48 percent of the 634 known species and sub-species of primates, humankind's closest relatives such as chimpanzees, orangutans, gibbons and lemurs, were at risk of extinction.
(Reporting by Maggie Fox; Editing by Julie Steenhuysen and Sandra Maler)
Gorilla "Paradise" Found; May Double World Numbers
Dan Morrison, National Geographic News 5 Aug 08;
Deep in the hinterlands of the Republic of the Congo lies a secret ape paradise that is home to 125,000 western lowland gorillas, researchers announced today.
The findings, if confirmed, would more than double the world's estimated population of gorillas.
Western lowland gorillas are a subspecies classified as critically endangered by the International Union for Conservation of Nature (IUCN).
Their numbers have been devastated in recent years by illegal hunting for bush meat and the spread of the Ebola virus. Just last year scientists projected the animals' population could fall as low as 50,000 by 2011.
Now those predictions may have to be dramatically reworked to incorporate findings released today by the Wildlife Conservation Society (WCS).
A first ever ape census in northern Congo found 73,000 of the gorillas in that country's Ntokou-Pikounda region and 52,000 more in the Ndoki-Likouala area.
The Ndoki population includes an obscure group of nearly 6,000 gorillas living in close quarters in isolated swamps near Lac Télé.
"We knew there were apes there, we just had no idea how many," said WCS's Emma Stokes, one of the lead researchers in the two-year project.
The gorillas have thrived thanks to their remoteness from human settlements, food-rich habitats, and two decades of conservation efforts in one of the world's poorest countries, Stokes said.
Shy, But Plentiful
Lowland gorillas are more common than their mountain cousins. The animals are found in tropical forests and swamps in Angola, Cameroon, the Central African Republic, Congo, the Democratic Republic of the Congo, Equatorial Guinea, and Gabon.
Wary of humans, gorillas are notoriously hard to tally in the wild.
To assess their populations, WCS researchers instead used data on the numbers and ages of so-called sleep nests, temporary bedding made of leaves and branches.
Each group of lowland gorillas has a range of about 7.7 square miles (20 square kilometers), and the animals build the nests to sleep in each night before moving on in the morning.
The census work involved crossing hundreds of miles to count nests, then loading data into a mathematical model that estimated the number of gorillas living within a defined area.
In the 17,400-square-mile (28,000-square-kilometer) Ndoki-Likouala region, for example, the nest census found an estimated population density of 1.65 gorillas per square kilometer (equal to about 0.3 square mile).
This means that about 46,200 western lowland gorillas likely live in the area, which runs west of the Sangha River to the border of the Central African Republic.
An additional 6,000 gorillas reside in the region's 646-square-mile (1,040-square-kilometer) Batanga swamps. These wetlands, which are inaccessible to humans for more than half the year, house an estimated five to six apes per square kilometer.
"That's the highest density I've seen," Stokes said, adding that the data suggest Ndoki-Likouala is the subspecies' "largest remaining stronghold."
The discovery "shows that conservation in the Republic of Congo is working," said WCS president Steven Sanderson.
Almost half the surveyed area lies within officially protected zones or inside timber concessions where logging companies have banned transport of protected animals and weapons on their roads.
Researchers hope the latest census will encourage the government of Congo to establish a new national park in the Ntokou-Pikounda region.
The census was presented today at the International Primatological Society conference in Edinburgh, Scotland, and some of the data will appear in an upcoming issue of the conservation journal Oryx.
Perils of Counting Apes
Several experts greeted the survey findings with a mix of excitement and caution.
"If these new gorilla census figures are confirmed by further surveys, it would be the most exciting ape conservation news in years," said Craig Stanford of the Jane Goodall Research Center at the University of Southern California.
"Nest census data are notorious for varying from one method to the next, however, and I think we should be cautious before assuming the world's known gorilla population has just doubled."
Nesting data were among the factors used in a 2007 IUCN population assessment that placed the western lowland gorilla on the organization's Red List of Threatened Species.
IUCN estimated the gorillas had declined by more than 60 percent over the past 25 years, and its scientists projected the apes' population could fall to 50,000 as the deadly Ebola virus penetrated deeper into their habitat.
That report came with a caveat about the reliability of nest counts: "Technical problems with the conversion of ape nest density to estimates of gorilla density preclude a rigorous estimate of range-wide gorilla abundance."
Peter Walsh of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, led the 2007 IUCN assessment. He repeated those concerns when he learned of WCS's findings in northern Congo.
"It is not that I think that the numbers are necessarily too high," Walsh said. "It is just that I do not trust the assumptions made by the estimation models that are being used."
Nature's Secrets
John Oates, professor emeritus of anthropology at Hunter College in New York, noted that "what does seem clear is that there are still plenty of western gorillas in northern Congo."
He remains cautious, however, about whether the new research should signal a change in status for the great apes.
In addition to habitat loss and hunting, in recent years Ebola has ravaged gorilla habitats bordering the Ntokou-Pikounda survey area, killing 60 percent of the apes in nearby Odzala National Park.
While WCS's Stokes said her survey found "no evidence of Ebola in Ntokou-Pikounda, our general philosophy is Ebola can hit anywhere, anytime."
And with a 90 percent mortality rate among infected gorillas, Stokes thinks the animals deserve all the protection they can get.
In general, the WCS findings demonstrate that our intensely observed planet still has its biological secrets, added Richard Bergl, curator of research at the North Carolina Zoo.
"It is extraordinary that in this day and age," he said, "there could be a population of a hundred thousand or more gorillas that were essentially unknown to science."
'Mother lode' of western lowland gorillas found
Auslan Cramb, The Telegraph 5 Aug 08;
The world population of endangered gorillas is far higher than previously thought according to scientists who have found "massive numbers" of the great apes in central Africa.
A new census discovered around 125,000 western lowland gorillas - one of four sub-species - in an area the size of Switzerland in the remote forests of the Republic of Congo.
Previous estimates from the 1980s suggested the entire population of the sub-species in seven African nations was less than 100,000 and it was feared half that number may have been lost to hunting and disease.
The latest discovery has been described as the "mother lode of gorillas".
Western lowland gorillas are the biggest sub-species of gorilla and the census carried out in 2006-07 means there are over twice as many of the great apes as previous best estimates suggested.
There are said to be less than 700 mountain gorillas surviving, 300 cross river gorillas and an unknown number of eastern lowland gorillas, although the figure is thought to be in the thousands.
However, the western lowland gorilla is unlikely to have its status as a critically endangered species on the "red list" of animals changed as a result of the discovery.
The Wildlife Conservation Society, which announced its find at The International Primatological Society Congress in Edinburgh today, said the gorillas remained under serious threat from the Ebola virus, which is lethal to apes as well as humans, from commercial hunting for "bushmeat" and from loss of habitat.
The new figures are based on counting the nests of the secretive great apes, which are difficult to observe in dense rainforest.
Gorillas make a new nest to sleep in every night, and scientists working for the Bronx Zoo-based conservation society spent months counting nests in forest and swamp areas.
They found some of the highest gorilla densities ever recorded and Dr Steven Sanderson, president of the WCS, said the census proved that conservation in that area of the Congo was working.
He added: "This discovery should be a rallying cry for the world that we can protect other vulnerable and endangered species, whether they be gorillas in Africa, tigers in India, or lemurs in Madagascar."
Emma Stokes, who led the survey, said: "We knew from our own observatinos that there were a lot of gorillas out there, but we had no idea there were so many."
The society said a number of factors led to the high numbers including successful conservation management, the remoteness and inaccessibility of the rainforest and a food-rich habitat.
All gorillas apart from the eastern lowland sub-species - which is regarded as endangered - are classified by the International Union for Conservation of Nature as critically endangered.
The good news on gorillas was released on the same day that another report from the IUCN said nearly half the world's monkeys and apes were facing an increasing threat of extinction because of deforestation and hunting.
